Com-Tech 200 Amplifier Service Manual

POWER AMPLIFIER
SERVICE MANUAL

COM-TECH 200
®

Model CT200B

©1995 by CROWN INTERNATIONAL, INC.

Mailing Address: Shipping Address:
P.O. Box 1000 57620 C.R. 105
Elkhart, IN U.S.A. 46515- Elkhart, IN U.S.A. 46517
1000

Com-Tech®, ODEP® and Crown® are registered trademarks of Crown International, Inc.

K-SVCCT200
12-95

1
 Com-Tech 200 Amplifier Service Manual

The information furnished in this manual does not include all of the details of design, production, or variations of
the equipment. Nor does it cover every possible situation which may arise during installation, operation or
maintenance. If you need special assistance beyond the scope of this manual, please contact the Crown
Technical Support Group.

Mail: P.O. Box 1000 Elkhart IN 46515-1000

Shipping: 57620 C.R. 105 Elkhart IN 46517
Phone: (800) 342-6939/(219) 294-8200
FAX: (219) 294-8301

CAUTION AVIS
TO PREVENT ELECTRIC SHOCK DO
NOT REMOVE TOP OR BOTTOM À PRÉVENIR LE CHOC
COVERS. NO USER SERVICEABLE ÉLECTRIQUE N’ENLEVEZ
PARTS INSIDE. REFER SERVICING PAS LES COUVERTURES.
TO QUALIFIED SERVICE RIEN DES PARTIES
PERSONNEL. DISCONNECT UTILES À L’INTÉRIEUR.
POWER CORD BEFORE REMOVING DÉBRANCHER LA BORNE
REAR INPUT MODULE TO ACCESS AVANT D’OUVRIR LA
GAIN SWITCH. MODULE EN ARRIÈRE.

WARNING
TO REDUCE THE RISK OF ELECTRIC
SHOCK, DO NOT EXPOSE THIS
EQUIPMENT TO RAIN OR MOISTURE!

2
 Com-Tech 200 Amplifier Service Manual

Table of Contents

Introduction ............................................................ 4
Parts Information .................................................... 5
Specifications ......................................................... 6
Theory .................................................................... 7
Electrical Checkout Procedures ........................... 12
Parts List (Non Module) ........................................ 16
Module and Schematic Information ...................... 19
Q42762-7 Control Module Parts List ..................... 20
Q43215-5 Control Module Parts List ..................... 21
Q43244-5 Control Module Parts List ..................... 22
Q43242-9 Control Module Parts List ..................... 23
Q42706-4 Display Module Parts List .................... 24
Q42716-3 Output Module Parts List ..................... 25
Q42888-0 Output Module Parts List ..................... 26
Q42969-8 Output Module Parts List ..................... 27
Q43188-4 Output Module Parts List ..................... 28
Q43013-4 Main Module Parts List ........................ 29
Q43044-9 Main Module Parts List ........................ 32
Q43128-0 Main Module Parts List ........................ 35
Q43237-9 Main Module Parts List ........................ 38

3
 Com-Tech 200 Amplifier Service Manual

Introduction
This manual contains service information on Crown board may be built up with different parts to create
power amplifiers. It is designed to be used in conjunc- different modules. Note that Crown does not sell blank
tion with the applicable Owner's Manual. However, (unpopulated) circuit boards.
some important information is duplicated in this Ser-
vice Manual in case the Owner's Manual is not readily Each of the compact audio power amplifiers are de-
available. signed for professional or commercial use. Providing
high power amplification from 20Hz to 20KHz with
NOTE: THE INFORMATION IN THIS MANUAL IS INTENDED minimum distortion, they feature balanced inputs with
FOR USE BY AN EXPERIENCED TECHNICIAN ONLY! bridged and parallel monophonic capability. Specific
features vary depending on model family.
Scope
This Service Manual in intended to apply to all versions Warranty
of the CT-200B amplifier including the Amcron version. Each Owner's Manual contains basic policies as re-
The Parts Listings include parts specific for the US lated to the customer. In addition it should be stated
version and the European version (CT-200BE13). For that this service documentation is meant to be used
parts specific only to other versions contact the Crown only by properly trained service personnel. Because
Technical Support Group for help in finding part num- most Crown products carry a 3 Year Full Warranty
bers. (including round trip shipping within the United States),
all warranty service should be referred to the Crown
This Service Manual includes several sections. These Factory or Authorized Warranty Service Center. See
sections include Parts Information, Specifications, Volt- the applicable Owner’s Manual for warranty details. To
age Conversion, Circuit Theory, Electrical Test Proce- find the location of the nearest Authorized Service
dures, Non-Module Parts Lists, and Module Parts Center or obtain instructions for receiving Crown Fac-
Lists. Schematics are attached. Note that component tory Service please contact the Crown Technical Sup-
parts with circuit board comprise a complete module. port Group (within North America) or your Crown/
Module part numbers are always associated with a Amcron Importer (outside North America).
specific circuit board, although an unpopulated circuit

Crown
Technical Support Group
Factory Service
Parts Department

Mailing Address:
PO Box 1000
Elkhart, IN USA 46515-1000

Shipping Address:
57620 C.R. 105
Elkhart, IN USA 46517

Phone: (219) 294-8200

Toll Free: (800) 342-6939
FAX: (219) 294-8301

4
 Com-Tech 200 Amplifier Service Manual

Parts Information
General Information ment on a C.O.D. or pre-payment (check or credit
Later sections include both mechanical and electrical card) basis.
parts lists for this product. The parts listed are current
as of the date printed. Crown reserves the right to Terms
modify and improve its products for the benefit of its Normal terms are pre-paid. Net-30 Days applies to
customers. only those firms having pre-established accounts with
Crown. If pre-paying, the order must be packed and
Part Numbering System weighed before a total bill can be established, after
As of the printing of this manual, Crown is using two which an amount due will be issued and shipment
numbering systems. The elder system always uses made upon receipt of pre-payment. New parts re-
eight characters. The first character is a letter. Com- turned for credit are subject to a 10% re-stocking fee,
mon letters used are C, D, H, M, P, and Q. The second and authorization from the Crown Parts Department
through sixth characters are numbers. The numbers must be obtained before returning parts for credit.
build sequentially (for each prefix letter) as new parts
are added to our parts inventory system. (In some Crown is not a general parts warehouse. Parts sold by
cases there will be a space then a four character the Crown Parts Department are solely for servicing
number after the prefix letter; the space is considered Crown/Amcron products. Part prices and availability
a character.) The seventh character is usually a hy- are subject to change without notice.
phen, though it may be a letter to indicate a revision or
special note. The last character is called a check-digit,
and is useful to Crown for internal tracking.

Crown is in the process of converting to a new part

number system. Length may vary from eight to twelve
characters. There is still a letter prefix, then five num-
bers. These five numbers identify a type of part. The
seventh character is a hyphen. Remaining characters
identify the details of the type of part identified by the
first part of the number. Crown
Parts Department
Standard and Special Parts
Many smaller electrical and electronic parts used by Mailing Address:
Crown are stocked by and available from electronic PO Box 1000
supply houses. However, some electronic parts that Elkhart, IN USA 46515-1000
appear to be standard are actually special. A part
ordered from Crown will assure an acceptable re- Shipping Address:
placement. Structural items such as modules and 57620 C.R. 105
panels are available from Crown only. Elkhart, IN USA 46517

Ordering Parts Phone: (219) 294-8210

When ordering parts, be sure to give the product or: (219) 294-8211
model, and include a description and part number Toll Free: (800) 342-6939
(CPN/DPN) from the parts listing. Price quotes are FAX: (219) 294-8301
available on request.

Shipment
Shipment will be normally made by UPS or best other
method unless you specify otherwise. Shipments are
made to and from Elkhart, Indiana USA, only. Estab-
lished accounts with Crown will receive shipment freight
prepaid and will be billed. All others will receive ship-

5
 Com-Tech 200 Amplifier Service Manual

Specifications
Unless noted otherwise, all specifications are based Input Impedance: Nominally 20K ohms balanced; 10K
on driving an 8 ohm load per channel, both channels ohms unbalanced.
driven, the sensitivity switch in the 26dB position, the
AC supply is 120VAC at 60Hz. Crown specifications Output Impedance: <10 milliohms in series with <2
are guaranteed through the warranty period (normally microhenries.
3 years). Because our testing methods are more strin-
gent than our published specifications, every Crown Protection Systems: Output Device Emulation Protec-
amplifier will exceed its published specifications. tion (ODEP) limits drive in the event of dangerous
dynamic thermal conditions without interrupting power.
Power Current limiting for shorted load protection. DC/LF and
Power common mode output current Fault circuitry to mute
8 Ohm Stereo—110W/Ch audio. Delay of 4 seconds from turn on mutes amplifier
4 Ohm Stereo—150W/Ch to prevent dangerous turn-on transients.
70-V Line Stereo—105W/Ch
8 Ohm Bridge Mono—295W Mechanical
4 Ohm Parallel Mono—225W Input Connectors: Balanced three-terminal barrier block
2 Ohm Parallel Mono—300W for each channel on standard P.I.P.-BB module (in-
Bridge Mono, 140-V Line—210W cluded)
Parallel Mono, 70-V Line—210W
Output Connectors: Four-terminal barrier block.
Load Impedances: Rated for 16, 8, 4, 2, Ohm, and 70-V
use. Safe with all types of loads, even totally reactive Front Panel Controls: A front panel rocker switch used to
loads. power the amplifier on and off.

AC Mains: 120VAC at 60 Hz with standard three-wire Back Panel Controls: A three-position switch which se-
grounded connector for North American units; 100VAC, lects Stereo, Bridge-Mono, or Parallel-Mono mode. A
120VAC, 220VAC, and 240VAC at 50 or 60 Hz units are rotary potentiometer for each channel used to control
available when ordered country specific. Com-Tech output level. A two position recessed switch for each
amplifiers are not voltage convertable. channel selects between 8/4 ohm and 70-V modes. A
push button circuit breaker used to protect the power
Performance supply.
Frequency Response: ±0.1dB from 20 Hz to 20 kHz at 1
Watt. Internal Controls: A three-position switch selects 0.775V,
1.4V, or 26 dB voltage gain input sensitivity.
Phase Response: ±10° from 10 Hz to 20 kHz at 1 Watt.
Indicators: Amber Enable indicator shows on/off status
Signal to Noise Ratio: A-weighted, better than 105 dB of low-voltage power supply. A green indicator for
below full rated output. Better than 100 dB below full each channel shows the reserve energy status. If no
rated output from 20 Hz to 20 kHz. reserve energy is available the indicator will dim in
proportion to ODEP limiting. A yellow indicator for each
Total Harmonic Distortion (THD): <0.05% from 20 Hz to channel flashes in the event of distortion. And green
1 kHz, increasing linearly to 0.1% at 20 kHz at 500W. SPI (signal presence indicator) indicators show the
presence of output signal.
I.M. Distortion: <0.05% from less than 164 milliwatts to
520 W at 26 dB gain. Construction: Black splatter-coat steel chassis with
specially designed flow-through ventilation system.
Slew Rate: >13V per microsecond. (Slew rates are
limited to useful levels for ultrasonic/RF protection.) Mounting: Standard EIA 310 front-panel rack mount
with supports for supplemental rear corner mounting.
Damping Factor: >1000 from 10 Hz to 400 Hz.
Dimensions: 19 inches wide, 3.5 inches high, 16 inches
DC Offset: <10 millivolts. deep behind front mounting surface.

Weight: 29 lbs, 6.5 oz.

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 Com-Tech 200 Amplifier Service Manual

Theory
Overview
It should be noted that over time Crown makes im- Front End Operation
provements and changes to their products for various The front end is comprised of three stages: Balanced
reasons. This manual is up to date as of the time of Gain Stage (BGS), Variable Gain Stage (VGS), and the
writing. For additional information regarding these Error Amp. Figure 1 shows a simplified diagram of a
amplifiers, refer to the applicable Technical Notes typical front end with voltage amplification stages.
provided by Crown for this product.
Balanced Gain Stage (BGS)
This section of the manual explains the general opera- Input to the amplifier is balanced. The shield may be
tion of a typical Crown power amplifier. Topics covered isolated from chassis ground by an RC network to
include Front End, Grounded Bridge, and ODEP. Due interrupt ground loops via the Ground Lift Switch. The
to variations in design from vintage to vintage (and non-inverting (hot) side of the balanced input is fed to
similarities with other Crown products) the theory of the non-inverting input of the first op-amp stage. The
operation remains simplified. inverting (negative) side of the balanced input is fed to
the inverting input of the first op-amp stage. A poten-
Features tiometer is provided for common mode rejection ad-
Com-Tech amplifiers utilize numerous Crown innova- justment. Electrically, the BGS is at unity gain. (From an
tions including grounded bridge and ODEP technolo- audio perspective, however, this stage actually pro-
gies. Cooling techniques make use of the what is vides +6dB gain if a fully balanced signal is placed on
essentially air conditioner technology. Air flows bottom its input.) The BGS is a non-inverting stage. It’s output
to top, and front to side. Air flows a short distance is delivered to the Variable Gain Stage.
across a wide heatsink. This type of air flow provides
significantly better cooling than the “wind tunnel” tech- Variable Gain Stage (VGS)
nology used by many other manufacturers. Output From the output of the BGS, the signal goes to the VGS
transistors are of the metal can type rather than plastic where gain is determined by the position of the Sensi-
case. This allows for a significantly higher thermal tivity Switch, and level is determined by the level
margin for the given voltage and current ratings. All control. VGS is an inverting stage with the input being
devices used are tested and graded to ensure maxi- fed to its op-amp stage. Because gain after this stage
mum reliability. Another electronic technique used is is fixed at 26dB (factor of 20), greater amplifier sensi-
negative feedback. Almost all power amplifiers utilize tivity is achieved by controlling the ratio of feedback to
negative feedback to control gain and provide stabil- input resistance. The Sensitivity Switch sets the input
ity, but Crown uses multiple nested feedback loops for impedance to this stage and varies the gain such that
maximum stability and greatly improved damping. the overall amplifier gain is 26 dB, or is adjusted
Most Crown amplifiers have damping in excess of appropriately for 0.775V or 1.4V input to attain rated
1000 in the bass frequency range. This feedback, output.
along with our compensation and ultra-low distortion
output topology, make Crown amplifiers superior. Error Amp
The inverted output from the VGS is fed to the non-
Features specific to the Com-Tech Series’ include slew inverting input of the Error Amp op-amp stage through
rate limiting, and audio muting for delay or protective an AC coupling capacitor and input resistor. Amplifier
action. This amplifier can operate in either a Bridged or output is fed back via the negative feedback (NFb)
Parallel Mono mode as well as dual (stereo). A sensi- loop resistor. The ratio of feedback resistor to input
tivity switch allows selection of input voltage required resistor fixes gain from the Error Amp input to the
for rated output. Level controls are mounted on the rear output of the amplifier at 26 dB. Diodes prevent
panel and are of the rotary type. Front panel indicators overdriving the Error Amp. Because the Error Amp
let the user know the status of the low voltage power amplifies the difference between input and output
supply (enable), signal presence, distortion, and an signals, any difference in the two waveforms will pro-
ODEP indicator for each channel which shows the duce a near open loop gain condition which in turn
reserve energy status. In general, the packaging of this results in high peak output voltage. The output of the
model is designed for maximum watt/price/weight/ Error Amp, called the Error Signal (ES) drives the
size value with user friendly features. Voltage Translators.
For additional details refer to the specification section,
or to the applicable Owner’s Manual.
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 Com-Tech 200 Amplifier Service Manual

Theory
Voltage Amplification The Voltage Translator stage channels the signal to the
The Voltage Translator stage separates the output of Last Voltage Amplifiers (LVA's) in a balanced configu-
the Error Amp into balanced positive and negative ration. The +LVA and -LVA, with their push-pull effect
drive voltages for the Last Voltage Amplifiers (LVAs), through the Bias Servo, drive the fully complementary
translating the signal from ground referenced ±15V to output stage. The LVAs are configured as common
±Vcc reference. LVAs provide the main voltage ampli- emitter amplifiers. This configuration provides suffi-
fication and drive the High Side output stages. Gain cient voltage gain and inverts the audio. The polarity
from Voltage Translator input to amplifier output is a inversion is necessary to avoid an overall polarity
factor of 25.2. inversion from input jack to output jack, and it allows the
NFb loop to control Error Amp gain by feeding back to
Voltage Translators its non-inverting input (with its polarity opposite to the
A voltage divider network splits the Error Signal (ES) output of the VGS). With the added voltage swing
into positive and negative drive signals for the bal- provided by the LVAs, the signal then gains current
anced voltage translator stage. These offset reference amplification through the Darlington emitter-follower
voltages drive the input to the Voltage Translator tran- output stage.
sistors. A nested NFb loop from the output of the
amplifier mixes with the inverted signal riding on the Grounded Bridge Topology
offset references. This negative feedback fixes gain at Figure 2 is a simplified example of the grounded bridge
the offset reference points (and the output of the Error output topology. It consists of four quadrants of three
Amp) at a factor of -25.2 with respect to the amplifier deep Darlington (composite) emitter-follower stages
output. The Voltage Translators are arranged in a per channel: one NPN and one PNP on the High Side
common base configuration for non-inverting voltage of the bridge (driving the load), and one NPN and one
gain with equal gain. They shift the audio from the ±15V PNP on the Low Side of the bridge (controlling the
reference to VCC reference. Their outputs drive their ground reference for the rails). The output stages are
respective LVA. biased to operate class AB+B for ultra low distortion in
the signal zero-crossing region and high efficiency.
Also tied into the Voltage Translator inputs are ODEP
limiting transistors and control/protection transistors. High Side (HS)
The ODEP transistors steal drive as dictated by the The High Side (HS) of the bridge operates much like a
ODEP circuitry (discussed later). The control/protec- conventional bipolar push-pull output configuration.
tion transistors act as switches to totally shunt audio to As the input drive voltage becomes more positive, the
ground during the turn-on delay, or during a DC/LF or HS NPN conducts and delivers positive voltage to the
Fault protective action. load. Eventually the NPN devices reach full conduction
and +Vcc is across the load. At this time the HS PNP is
Last Voltage Amplifiers (LVAs)

+15V Voltage +VCC

BGS VGS Error Translators
Amp
Voltage Divider

Q105
Q100 Q121 Q101
Audio + + + NPN Outputs (+HS)
Q102
Inputs - - - PNP Outputs (-HS)
Q103
Q122 Q110

-+ Mute
-15V ODEP -VCC

NFb Loop LVA's

Figure 1. Typical Amplifier Front End and Voltage Amplification Stages.

8
 Com-Tech 200 Amplifier Service Manual

Theory
biased off. When the drive signal is negative going, the predrivers and drivers, the balance of voltage results
HS PNP conducts to deliver -Vcc to the load and the HS in approximately .35V drop across the bias resistors in
NPN stage is off. the positive half, and about .5V across the bias resistor
in the negative half. Q18 conduction (and thus bias) is
The output of the +LVA drives the base of predriver adjustable.
device. Together, the predriver and driver form the first
two parts of the three-deep Darlington and are biased A diode string prevents excessive charge build up
class AB. They provide output drive through the bias within the high conduction output devices when off.
resistor, bypassing the output devices, at levels below Flyback diodes shunt back-EMF pulses from reactive
about 100mW. An RLC network between the predriver loads to the power supply to protect output devices
and driver provide phase shift compensation and limit from dangerous reverse voltage levels. An output
driver base current to safe levels. Output devices are terminating circuit blocks RF on output lines from
biased class B, just below cutoff. At about 100mW entering the amplifier through its output connectors.
output they switch on to conduct high current to the
load. Together with predriver and driver, the output Low Side (LS)
device provide an overall class AB+B output. The Low Side (LS) operates quite differently. The
power supply bridge rectifier is not ground referenced,
The negative half of the HS is almost identical to the nor is the secondary of the main transformer. In other
positive half, except that the devices are PNP. One words, the high voltage power supply floats with re-
difference is that the PNP bias resistor is slightly spect to ground, but ±Vcc remain constant with re-
greater in value so that PNP output devices run closer spect to each other. This allows the power supply to
to the cutoff level under static (no signal) conditions. deliver +Vcc and -Vcc from the same bridge rectifier
This is because PNP devices require greater drive and filter as a total difference in potential, regardless of
current. their voltages with respect to ground. The LS uses
inverted feedback from the HS output to control the
HS bias is regulated by Q18, the Bias Servo. Q18 is a ground reference for the rails (±Vcc). Both LS quad-
Vbe multiplier which maintains approximately 3.3V rants are arranged in a three-deep Darlington and are
Vce under static conditions. The positive and negative biased AB+B in the same manner as the HS.
halves of the HS output are in parallel with this 3.3V.
With a full base-emitter on voltage drop across

+
+Vcc (Positive Rail)

Input
signal
Load
(speaker)
Inverting Op-amp

HIGH SIDE -Vcc (Negative Rail) LOW SIDE

Figure 2. Crown Patented Grounded Bridge Topology

9
 Com-Tech 200 Amplifier Service Manual

Theory
When the amplifier output swings positive, the audio is To further protect the output stages, a specially devel-
fed to an op-amp stage where it is inverted. This oped ODEP circuit is used. It produces a complex
inverted signal is delivered directly to the bases of the analog output signal. This signal is proportional to the
positive (NPN) and negative (PNP) LS predrivers. The always changing safe-operating-area margin of the
negative drive forces the LS PNP devices on (NPN off). output transistors. The ODEP signal controls the Volt-
As the PNP devices conduct, Vce of the PNP Darlington age Translator stage by removing drive that may
drops. With LS device emitters tied to ground, -Vcc is exceed the safe-operating-area of the output stage.
pulled toward ground reference. Since the power
supply is not ground referenced (and the total voltage ODEP senses output current by measuring the voltage
from +Vcc to -Vcc is constant) +Vcc is forced higher dropped across LS emitter resistors. LS NPN current
above ground potential. This continues until, at the (negative amplifier output) and +Vcc are sensed, then
positive amplifier output peak, -Vcc = 0V and +Vcc multiplied to obtain a signal proportional to output
equals the total power supply potential with a positive power. Positive and negative ODEP voltages are ad-
polarity. If, for example, the power supply produced a justable via two potentiometers. Across ±ODEP are a
total of 70V from rail to rail (±35VDC measured from PTC and a thermal sense (current source). The PTC is
ground with no signal), the amplifier output would essentially a cutoff switch that causes hard ODEP
reach a positive peak of +70V. limiting if heatsink temperature exceeds a safe maxi-
mum, regardless of signal level. The thermal sense
Conversely, during a negative swing of the HS output causes the differential between +ODEP and –ODEP to
where HS PNP devices conduct, the op-amp would decrease as heatsink temperature increases. An in-
output a positive voltage forcing LS NPN devices to crease in positive output signal output into a load will
conduct. This would result in +Vcc swinging toward result in –ODEP voltage dropping; an increase in
ground potential and -Vcc further from ground poten- negative output voltage and current will cause +ODEP
tial. At the negative amplifier output peak, +Vcc = 0V voltage to drop. A complex RC network between the
and -Vcc equals the total power supply potential with ±ODEP circuitry is used to simulate the thermal barri-
a negative polarity. Using the same example as above, ers between the interior of the output device die (im-
a 70V supply would allow a negative output peak of - measurable by normal means) and the time delay from
70V. In summary, a power supply which produces a heat generation at the die until heat dissipates to the
total of 70VDC rail to rail (or ±35VDC statically) is thermal sensor. The combined effects of thermal his-
capable of producing 140V peak-to-peak at the ampli- tory and instantaneous dynamic power level result in
fier output when the grounded bridge topology is used. an accurate simulation of the actual thermal condition
The voltage used in this example are relatively close to of the output transistors.
the voltages of the PB-1/460CSL.

The total effect is to deliver a peak to peak voltage to

the speaker load which is twice the voltage produced
by the power supply. Benefits include full utilization of
the power supply (it conducts current during both
halves of the output signal; conventional designs re-
quire two power supplies per channel, one positive
and one negative), and never exposing any output
device to more than half of the peak to peak output
voltage (which does occur in conventional designs).

Low side bias is established by a diode string which

also shunts built up charges on the output devices.
Bias is adjustable via potentiometer. Flyback diodes
perform the same function as the HS flybacks. The
output of the LS is tied directly to chassis ground via
ground strap.

Output Device Emulation Protection (ODEP)

10
 Com-Tech 200 Amplifier Service Manual

Theory

POSITIVE
+VOLTAGE +LVA HIGH SIDE
TRANSLATOR -1 OUTPUT
NPN STAGE
ERROR
BGS VGS
AMP

OUTPUT
HIGH SIDE
BALANCED DEVICE
-1 EMULATION
BIAS
INPUTS SERVO
PROTECTION

NEGATIVE
-VOLTAGE -LVA HIGH SIDE
TRANSLATOR -1 OUTPUT
PNP STAGE

MAIN NEGATIVE FEEDBACK (NFb) LOOP

POSITIVE
LOW SIDE
OUTPUT
NPN STAGE
LOW SIDE
-1 BIAS
DIODE
STRING
NEGATIVE
INVERTING LOW SIDE
BRIDGE OUTPUT
BALANCE PNP STAGE

Figure 3. Typical Crown Amplifier Basic Block Diagram (One Channel Shown)

11
 Com-Tech 200 Amplifier Service Manual

Electrical Checkout Procedures

General Information The following list of ODEP bias voltages VS. tempera-
The following test procedures are to be used to verify ture is based on the use of Main Modules built on any
operation of this amplifier. DO NOT connect a load or circuit board up to and including the D 7911-7 board.
inject a signal unless directed to do so by the proce- °F °C V–ODEP V+ODEP
dure. These tests, though meant for verification and 66 18.9 –10.31 11.41
alignment of the amplifier, may also be very helpful in 68 20.0 –10.26 11.36
troubleshooting. For best results, tests should be per- 70 21.1 –10.20 11.30
formed in order. 72 22.2 –10.14 11.24
74 23.3 –10.09 11.19
All tests assume that AC power is from a regulated 120 76 24.4 –10.03 11.13
VAC source. Test equipment includes an oscilloscope, 77 25.0 –10.00 11.10
a DMM, a signal generator, loads, and I.M.D. and 78 25.6 –9.97 11.07
T.H.D. noise test equipment. 80 26.7 –9.91 11.01
82 27.8 –9.86 10.96
Standard Initial Conditions 84 28.9 –9.80 10.90
Level controls fully clockwise. 86 30.0 –9.74 10.84
Stereo/Mono switch in Stereo. 88 31.1 –9.69 10.79
Sensitivity switch in 26 dB fixed gain position. 90 32.2 –9.63 10.73
70-V mode switches in the 8/4 ohm position. 92 33.3 –9.57 10.67
It is assumed, in each step, that conditions of the 94 34.4 –9.51 10.61
amplifier are per these initial conditions unless other-
wise specified. The following list of ODEP bias voltages VS. tempera-
ture is based on the use of Main Modules built on the
D 7993-5 board.
Test 1: DC Offset °F °C V-ODEP V+ODEP
Spec: 0 VDC, ±10 mV. 66 18.9 -9.31 10.31
Initial Conditions: Controls per standard, inputs shorted. 68 20.0 -9.26 10.26
Procedure: Measure DC voltage at the output connec- 70 21.1 -9.20 10.20
tors (rear panel). There is no adjustment for output 72 22.2 -9.14 10.14
offset. If spec is not met, there is an electrical malfunc- 74 23.3 -9.09 10.09
tion. Slightly out of spec measurement is usually due to 76 24.4 -9.03 10.03
U104/U204 out of tolorance. 77 25.0 -9.00 10.00
78 25.6 -8.97 9.97
Test 2: Output Bias Adjustment 80 26.7 -8.91 9.91
Spec: 300 to 320 mVDC. 82 27.8 -8.86 9.86
Initial Conditions: Controls per standard, heatsink tem- 84 28.9 -8.80 9.80
perature less than 40°C. 86 30.0 -8.74 9.74
Procedure: Measure DC voltages on the output module 88 31.1 -8.69 9.69
across R31 (15 ohm), adjust R26 if necessary. Mea- 90 32.2 -8.63 9.63
sure DC voltages on the output module across R32 (15 92 33.3 -8.57 9.57
ohm), adjust R23 if necessary. Repeat for second 94 34.4 -8.51 9.51
channel.
The following list of ODEP bias voltages VS. tempera-
Test 3: ODEP Voltage Adjustment ture is based on the use of Main Modules built on any
Spec: Bias Per Chart, ±0.1V DC. circuit board after the D 7993-5 board.
Initial Conditions: Controls per standard, heatsink at °F °C V–ODEP V+ODEP
room temperature 20 to 30°C (68 to 86°F). Note: This 66 18.9 –10.31 10.31
adjustment should normally be performed within 2 68 20.0 –10.26 10.26
minutes of turn on from ambient (cold) conditions. If 70 21.1 –10.20 10.20
possible measure heatsink temperature, if not mea- 72 22.2 –10.14 10.14
sure ambient room temperature. Use this information 74 23.3 –10.09 10.09
when referencing the following chart. 76 24.4 –10.03 10.03

12
 Com-Tech 200 Amplifier Service Manual

Electrical Checkout Procedures

77 25.0 –10.00 10.00 output. Inject a 0.775 VAC 1 kHz sine wave with the
78 25.6 –9.97 9.97 Sensitivity Switch in the 0.775V 8/4 ohm position.
80 26.7 –9.91 9.91 Measure 28.9 VAC ±1.7 VAC at the amplifier output.
82 27.8 –9.86 9.86 Inject a 0.775 VAC 1 kHz sine wave with the Sensitivity
84 28.9 –9.80 9.80 Switch in the 0.775 VAC 70-V position and the Output
86 30.0 –9.74 9.74 Mode Switch in the 70-V position. Measure 70.7 VAC
88 31.1 –9.69 9.69 ±4.2 VAC at the amplifier output. Return the Sensitivity
90 32.2 –9.63 9.63 Switch to the 26 dB position. Return the Output Mode
92 33.3 –9.57 9.57 Switches to the 8/4 ohm position.
94 34.4 –9.51 9.51
Test 7: Phase Response
–ODEP Procedure: Measure pin 3 of J500 and, if neces- Spec: ±10° from 10 Hz to 20 kHz at 1 Watt.
sary, adjust R121 to obtain V–ODEP as specified above. Initial Conditions: Controls per standard, 8 ohm load on
Measure pin 3 of J500 and, if necessary, adjust R221 each channel.
to obtain V–ODEP as specified above. Procedure: Inject a 1 kHz sine wave and adjust for 1 watt
+ODEP Procedure: Measure pin 4 of J500 and, if neces- output (2.8 VAC). Check input and output signals
sary, adjust R132 to obtain V+ODEP as specified above. against each other, input and output signals must be
Measure pin 4 of J500 and, if necessary, adjust R232 within 10° of each other.
to obtain V+ODEP as specified above.
Test 8: Level Controls
Test 4: AC Power Draw Spec: Level controlled by level controls.
Spec: 60 Watts maximum quiescent. Initial Conditions: Controls per standard.
Initial Conditions: Controls per standard. Procedure: No load. Inject a 1 kHz sine wave. With level
Procedure: With no input signal and no load, measure controls fully clockwise you should see full gain. As
AC line wattage draw. If current draw is excessive, controls are rotated counterclockwise, observe similar
check for high AC line voltage or high bias voltage. gain reduction in each channel. When complete, return
level controls to fully clockwise position.
Test 5: Common Mode Rejection
Spec at 100 Hz: –70 dB. Test 9: Current Limit
Spec at 20 kHz: –50 dB. Spec: Current Limit at 13 Amps, ±2 Amps.
Initial Conditions: Controls per standard. Initial Conditions: Controls per standard.
Procedure: No load. Inject a 0 dBu (.775VRMS) 100 Hz Procedure: Load each channel to 1 ohm. Inject a 1 kHz
sine wave into each channel, one channel at a time, differentiated (or 10% duty cycle) square wave. See
with inverting and non-inverting inputs shorted to- figure 4. Increase output level until current limit occurs.
gether. At the output measure less than –44 dBu Current limit should occur at 13 ±2 Amps (13 Vpk).
(4.9mVRMS). Inject a 0 dBu 20 kHz sine wave into each Observe clean (no oscillations) current clipping.
channel, one channel at a time, with inverting and non-
inverting inputs shorted together. At the output mea-
sure less than –24 dBu (49mVRMS). For Main Modules
with board numbers lower than D 7993-5 adjust N100
and N200 to calibrate CMR. For Main Modules with
board number D 7993-5 or greater adjust R921 and In Out
R1021. .047 uF
1K Ohm
Test 6: Voltage Gain
Spec 26dB Gain: Gain of 20.0 ±3%.
Spec 0.775V 8/4 ohm Sensitivity: ±6%.
Spec 0.775V 70-V Sensitivity: ±6%.
Initial Conditions: Controls per standard. Figure 4. Differentiator Circuit
Procedure: No load connected. Inject a 0.775 VAC 1
kHz sine wave with the Sensitivity Switch in the 26 dB
position. Measure 15.5 VAC ±0.5 VAC at the amplifier

13
 Com-Tech 200 Amplifier Service Manual

Electrical Checkout Procedures

Test 10: Slew Rate & 10 KHz Square Wave Procedure Short: Inject a 60 Hz sine wave into the input
Spec: 17 - 25 V/µS, 8 ohm load. and adjust for 5 VAC at the output. Short each chanel,
Initial Conditions: Controls per standard. one at a time, for 10 seconds.
Procedure: Load each channel to 8 ohms. Inject a 10
kHz square wave to obtain 35 Volts zero-to-peak at Test 14: ODEP Limiting
each output. Observe the slope of the square wave. It Spec: No oscillation on ODEP limiting wave form; either
should typically measure 17-25 V/µS. Also, the square channel controls limiting in Parallel Mono mode.
wave must not include overshoot, ringing, or any type Initial Conditions: Controls per standard; rag or other
of oscillation. obstruction blocking fan blade so it does not turn (if
FAN is installed).
Test 11: Crosstalk Procedure: Load the amplifier to 2 ohms per channel.
Spec: -60 dB at 20 kHz. Inject a 60 Hz sine wave into each channel and adjust
Initial Conditions: Controls per standard. Terminate the output to 10 VAC. Allow the amplifier to heat up until
input of channel not driven with 600 ohms. you observe a wave form similar to figure 5. Allow the
Procedure: 8 ohm load on each channel. Inject a 20 kHz amplifier to cool for a few miniutes. Switch the amplifier
sine wave into the channel 1 input and increase output to Parallel Mono mode and remove the load from
level to 29 VAC. Measure less than 29 mVAC at the channel 2. Inject a 60 Hz sine wave into each channel
output of channel 2. Inject a 20 kHz sine wave into the and adjust the output to 10 VAC. Allow the amplifier to
channel 2 input and increase output level to 29 VAC. heat up and observe limiting on both channels.
Measure less than 29 mVAC at the output of Ch 1.

Test 12: Output Power

Spec at 8 Ohm Stereo: ≥ 105 Watts/Ch at 0.1% THD
Spec at 4 Ohm Stereo: ≥ 140 Watts/Ch at 0.1% THD
Spec at 70-V Mode, Stereo: ≥ 100 Watts/Ch at 0.1% THD,
50 Ohm load.
Initial Conditions: Controls per standard
Procedure: Load each channel to 8 ohms. Inject a 1 kHz
sine wave and measure at least 28.98 VAC at the
output of each channel. Load each channel to 4 ohms.
Inject a 1 kHz sine wave and measure at least 23.66
VAC at the output of each channel. Switch each chan-
nel to the 70-V mode. Load each channel to 50 ohms.
Inject a 1 kHz sine wave and measure at least 70.7 VAC
at the output of each channel. All power measurements
must be at less than 0.1% THD.

Test 13: Reactive Loads

Spec: No oscillations. Safe with all types of loads.
Initial Conditions: Controls per standard.
Procedure Capacitive: Load each channel to 8 ohms in
parallel with 2µF. Inject a 20 kHz sine wave with 22 VAC Figure 5. ODEP Limiting Wave Form
output for 10 seconds.
Procedure Inductive: Load each channel to 8 ohms in
parallel with 159µH. Inject a 1 kHz sine wave with 15
VAC output for 10 seconds. Test 15: LF Protection
Procedure Torture: Load each channel with the primary Spec: Amplifier mutes for dangerous subsonic fre-
(red and black leads) of a PS-U transformer (CPN D quencies.
7040-5). Each channel in the 70-V mode. Inject a 10 Hz Initial Conditions: Controls per standard.
sine wave with an output level sufficient enough to Procedure: No load. Inject a .5 Hz 6 Vp-p, or a 2 Hz 6
cause 3 to 5 flyback pulses for 10 seconds. VAC sine wave into each channel and verify that each
channel cycles into mute.

14
 Com-Tech 200 Amplifier Service Manual

Electrical Checkout Procedures

Test 16: Signal to Noise Ratio Test 19: Clipping
Spec: ≥ 100 dB below 8 ohm rated continuous average Spec: No protective action during test.
20-20kHz power. Initial Conditions: Controls per standard.
Initial Conditions: Controls per standard. Short inputs. Procedure: Load each channel to 8 ohms. Inject a 1 kHz
Procedure: Load each channel to 8 ohms. Measure less sine wave into each input and drive the output 6 dB into
than 290µV at the output of each channel (20 Hz-20 clip for 10 seconds. The amplifier should not activate
kHz bandpass filter). any protective circuits (ODEP, Fault, or LF Protection).

Test 17: Turn off Transients Post Testing

Spec: < 80mV across an 8 ohm speaker load After completion of testing, if all tests are satisfactory,
Initial Conditions: Controls per standard. the amplifier controls should be returned to the posi-
Procedure: Load the output with an 8 ohm speaker. tions required by customer. If conditions are unknown
From an on condition, turn off the amplifier and monitor or unspecified, factory settings are as follows:
the output noise at the time of turn off. Level Controls: 9 to 11 O'Clock.
Note: Turn off noise may increase significantly if the Sensitivity Switch: 0.775V 8/4 Ohm.
amplifier is cycled off and on. Stereo/Mono Switch: Stereo.
70-V Mode Switches: 8/4 Ohm position.
Test 18: Intermodulation Distortion Power: Off
Spec at 0 dB output: ≤ 0.01%.
Spec at -35 dB output: ≤ 0.05%.
Initial Conditions: Controls per standard.
Procedure: Load each channel to 8 ohms. Inject a
SMPTE standard IM signal (60 Hz and 7 kHz sine wave
mixed at 4:1 ratio). Set the 60 Hz portion of the sine
wave to 23 volts RMS. Set the 7 kHz portion to 25%.
With an IM analyzer measure less than 0.01% IMD.
Repeat test at -35 dB (reference 23 volts RMS, 60 Hz
portion) and measure less than 0.05% IMD.

15
 Com-Tech 200 Amplifier Service Manual

Parts List (Non-Module)

Supplimental Items
CPN Item Quantity
A10087-71012 Rack Screw, 10-32 x .75 8
C 3342-0 Feet, Selfstick Black 4
D 4137-2 Nylon Washer 4
A10086-70808 Screw, 8-32 x .5 (For volume cover) 2
A10101-12 Spacer, #8 x 5/16OD x 1/4L (For volume cover) 2
F11489-6 Plexiglass Plate (Volume cover) 1
K80636-2 CT Series Reference Manual 1

Power Supply
CPN Item Quantity
A10087-11028 Screw, 10-32 x 1.75 (For transformer) 4
C 10171-4 Breaker, 8 Amp VDE 1
C10168-0 Breaker, 4 Amp VDE (200V-240V Models) 1
D 7212-0 Power Transformer (120V 60 Hz) 1
D 7224-5 Power Transformer (220V/240V) 1
D 8022-2 Power Transformer (100V/120V) 1
A10099-7 Nylon Shoulder Washer, #10 4
A10095-4 Lockwasher, #10 External Star 4
A10098-5 Washer, 1/4" Belleville Spring 4
C 8752-5 Bridge Rectifier, 35A 400V 2
C 9852-2 Capacitor, 6300µF 200V Electrolytic 2
C 9870-4 Screw, 10-32 x .38 4
D 2934-4 Solder Lug, .218 Hole 4
D 6764-1 Washer, Shoulder 4
D 8438-0 Bracket, Capacitor 2

Output Assembly (One Per Channel)

CPN Item Quantity (Per Channel)
A10315-1 Screw, 6-32 x .56 Hex Washer Head 12
C 8188-2 Output Power Transistor, PNP 2
D 6729-4 Output Power Transistor, NPN 2
C 7065-3 Output Power Transistor, PNP (early units) 2
C 8573-5 Driver Transistor, 2SA1186 PNP 2
C 8574-3 Driver Transistor, 2SC2837 NPN 2
M20591-0 Old Style Driver Transistor Assm. NPN, 2SC2527 2
M20590-2 Old Style Driver Transistor Assm. PNP, 2SA1077 2
D 7665-9 Mounting Clip, TO3P (For Drivers) 2
D 7666-7 Mounting Bracket, TO3P (For Drivers) 2
D 7796-2 Sil Pad, 2.87 x 14.57 (Between Heatsink & Chassis) 1
D 6280-8 Sil Pad for use with Output Board P10315-3 1
D 6104-0 Sil Pad for use with Output Board P10233-8 1
D 7797-0 Output Pad (Between Module and Chassis) 1
C 7597-4 Output Pad for use with Output Board P10315-3 1
D 7026-4 Output Pad for use with Output Board P10233-8 1
D 8774-8 PTC, 95DegC Cast Alum. 1
F12019-0 Heatsink (Under Diode String) 1
C 8813-5 Bias Transistor MPS8097/MPSA18 NPN (Q18) 1
B 5842-8 Tubing, #24 Thin Wall Red (For Q18) Order in Inches
C 5826-0 LM234Z-6 Thermal Sense (S100/200) 1
B 5464-1 Tubing, #24 Teflon Thin Wall Order in Inches
M21324-5 Aluminum Heat Sink, 3/4" With Fins 2
16
 Com-Tech 200 Amplifier Service Manual

Parts List (Non-Module)

Back Panel Assembly
CPN Item Quantity
D 8367-1 Knob, .5 Dia. Level Control 2
A10086-10410 Screw, 4-40 x .62 2
A10086-70808 Screw, 8-32 x .5 4
A10094-2 Lockwasher, #4 Internal Star 2
A10100-7 Aluminum Spacer, .250OD x .140ID x .312L 2
A10109-70808 Screw, 8-18 x .5 4
A10214-4 Strain Relief 1
C10187-0 Strain Relief (For European Power Cord) 1
A11793-0105D Power Cord, 16-3 SJT Neon UL/CSA 1
A10793-0503D Power Cord, European Plug (E-13 Amplifiers) 1
C 4508-5 IC Socket, 16 Pin 1
C 5990-4 Barrier Block, 4 Term. 1
C 6821-0 Edge Card Connector, 22 Contact 1
C 7957-1 Slide Switch, DPDT 15A (70-V Mode) 2
C 8812-7 Cable Tie, 5.5" 2
C10060-9 Header, 5 Pin R Angle Locking 1
D 6899-5 Ribbon Connector, PIP Daisy 1
D 7623-8 Cable, 10" 22AWG With Terminals 1
F12690-8 Back Panel 1
P10286-6 PIP Interconnect Board 1

Chassis Front Assembly

CPN Item Quantity
A10031-1 Captive Nut, 8-32 x .060 Flush (For rack ears) 4
A10090-70808 Screw, 8-32 x .5 Oval Head (For Grille) 3
A10101-5 Nylon Washer, .5 x .136 x .02 (For Grille) 3
A10173-1 Clip, Filter Grille 3
C 5297-4 Screw, 8-32 x .37 (For rack ears) 4
C 6487-0 Power Switch, 2 Pole 22 Amp Rocker 1
D 6944-9 Air Filter, 1.45 x 16.23 1
F11439J0 Front Panel Overlay 1
F12706-2 End Cap (For Rack ears) 2
F12710-4 Grille, Filter 1

Main Chassis Assembly

CPN Item Quantity
A10094-3 Washer, #6 Internal Star, Black 8
A10110-70605 Screw, 6-32 x .312 Taptite (For covers) 7
D 7249-2 Label, 3 Position Voltage Gain 1
D 8501-5 Top Cover 1
D 8548-6 Bottom Cover 1
A10086-10606 Screw, 6-32 x .375 4
A10086-70806 Screw, 8-32 x .37 1
A10094-3 Washer, #6 Internal Star, Black 3
A10094-6 Washer, #8 Internal Star 2
A10109-10822 Screw, 8-18 x 1.375 2
A10110-70812 8-32 x .750 Taptite 2
A10192-1 Snap Bushing, OCB .500 3
C 1811-6 4" Cable Tie 8
C 3163-0 Solder Lug, #6 2

17
 Com-Tech 200 Amplifier Service Manual

Parts List (Non-Module)

Main Chassis Assembly Cont.
CPN Item Quantity
C 6457-3 Screw, #8 x 3/8 2
C 6912-7 Tension Retaining Board Supports 2
C 6913-5 1" Spacer Toggle Nut, Plastic 2
C 6914-3 .75" Spacer Toggle Nut, Plastic 2
C 7705-4 Flat Cable Clamp 2
C 9491-9 Screw, 6-32 x .312 3
C 9953-8 Screw, 6-20 x .312 6
C10111-0 Button, Mtg. 2
D 7060-3 Sil Pad, 7 Mil 2.05 x .775 1
F11632-1 Bracket, Transformer Mtg. 1
F12642-9 Chassis, 3.5" 1

PIP-BB
CPN Item Quantity
M46011-9 PIP-BB Assembly 1
A10086-70806 Screw, 8-32 x .37 2
A10094-5 Lockwasher, #8 Internal Star Black 2
A10110-10608 Screw, 6-32 x .5 4
A10266-2202 Resistor, 22 Ohm .5W 2
C 3842-9 Barrier Block, 3 Position 2
C 6806-1 Capacitor, .01µF 100V 2
C 7161-0 Screw, #8 x 1/4 #6 PNHD 2
F12553J7 Panel 1
P10343-5 PC Board 1

CT-200 Fan Assembly (Optional on Domestic Units)

CPN Item Quantity
M44084-8 CT Fan Assembly 1
A10110-70605 Screw, 6-32 x .312 Taptite 2
C 7062-0 Screw, 6-32 x 5/16 2
C 9939-7 Fan Blade 1
D 8439-8 Fan Bracket 1
H43495-3 Fan Motor with Faston Connectors 1

18
 Com-Tech 200 Amplifier Service Manual

Module and Schematic Information

Module History Control Module:
The Com Tech 200B amplifier was introduced in 1990. Q42762-7
Since then there have been several updates and CT-200/400 fan control on P10317-9 board.
revisions, some of which called for new modules. The Q43215-5
following is a list of all modules used up to this date, CT-200 fan control on P10404-5 board.
December 1995. Q43244-5
CT control module for 120V, 60 Hz only. On P10405-2
Output Modules: (left and right are identical) board.
Q42716-3 Q43242-9
Original Output Module on P10233-8 or P10263-5 CT control module for Export models. On P10405-2
board. board.
Q42888-0
Output Module on P10315-3 board. Display Module:
Q42969-8 Q42706-4
Output Module on P10337-7 board. No longer avail- CT display on D 7083-5 board.
able. Use Q43188-4 as service replacement.
Q43188-4 Schematic Information:
Output Module on P10396-3 board. The schematics provided are representative only. There
may be slight variations between amplifier to amplifier.
Main Modules: These schematics are intended to be used for trouble-
Q42774-2 shooting purposes only.
Original B Version Main Module. This Module's parts
list is not documented. No longer available. Use For amplifiers with main boards D 7605-5, D 7911-7, D
Q43128-0 as a service replacement. 7993-5, and D 8283-0 or earlier, refer to schematic
Q42922-7 number J0552-3.
Main Module on D 7605-5 board. This Module's parts
list is not documented. No longer available. Use For amplifiers with main board D 8369-7 refer to sche-
Q23128-0 as a service replacement. matic number J0630-4.
Q43013-4
Main Module on D 7911-7 board. This module is still
available at this time. If not, then use Q43128-0 as a
service replacement.
Q43044-9
Main Module on D 7993-5 board. No longer available.
Use Q43128-0 as service replacement.
Q43128-0
Main Module on D 8283-0 board.
Q43237-9
Main Module on D 8369-7 board. Detent Pots. Not
reverse compatible.

19
 Com-Tech 200 Amplifier Service Manual

Q42762-7 Control Module (P10317-9 board) Parts Lists

Capacitors Resistors
C700 C800 C 8426-6 .1µF 250V R700 R800 A10266-1222 1.2K .5W
C701 C801 C 8426-6 .1µF 250V R701 R801 A10266-1812 180 .5W
C900 C 8963-8 .47µF 250V R900 A10266-2722 2.7K .5W
C901 C 8963-8 .47µF 250V R901 A10266-1021 1.5K .5W
R902 C 7669-2 300 10W
R903 C 7669-2 300 10W
Diodes R904 A10266-3902 39 .5W
D700 D800 C 3181-2 1N4148 R905 A10266-3602 36 .5W
D900 C 2851-1 1N4004

ICs
Relays U700 U800 C 7664-3 MOC3031 Optotriac
K1 C 7860-7 SPST U901 C 7665-0 MOC3011 Optotriac
U902 C 7665-0 MOC3011 Optotriac

Transistors
Q700 Q800 C 3625-8 PNP 2N4125 Misc.
Q701 Q801 C 7663-5 Triac MAC224A4 Board P10317-9
Q900 C 3625-8 PNP 2N4125 J900 C 7672-6 8 Pin MTA Header
Q901 C 3625-8 PNP 2N4125 Tab Terminal C 7817-7 W1-W3, W100-W102
Q902 C 3625-8 PNP 2N4125 W200-W202
0 Ohm Jmp C 5868-2

20
 Com-Tech 200 Amplifier Service Manual

Q43215-5 Control Module (P10404-5 board) Parts List

Capacitors Resistors
C700 C800 C 8426-6 .1µF 250V R700 R800 A10266-1222 1.2K .5W
C701 C801 C 8426-6 .1µF 250V R701 R801 A10266-1812 180 .5W
C900 C 8963-8 .47µF 250V R900 A10266-2722 2.7K .5W
C901 C 8963-8 .47µF 250V R901 A10266-1021 1.5K .5W
R902 C 7669-2 300 10W
R903 C 7669-2 300 10W
Diodes R904 A10266-3902 39 .5W
D700 D800 C 3181-2 1N4148 R905 A10266-3602 36 .5W
D900 C 2851-1 1N4004

ICs
Relays U700 U800 C 7664-3 MOC3031 Optotriac
K1 C 7860-7 SPST U901 C 7665-0 MOC3011 Optotriac
U902 C 7665-0 MOC3111 Optotriac

Transistors
Q700 Q800 C 3625-8 PNP 2N4125 Misc.
Q701 Q801 C 7663-5 Triac MAC224A4 Board P10404-5
Q900 C 3625-8 PNP 2N4125 J900 C 7672-6 8 Pin MTA Header
Q901 C 3625-8 PNP 2N4125 Tab Terminal C 7817-7 W1-W3, W100-W102
Q902 C 3625-8 PNP 2N4125 W200-W202

21
 Com-Tech 200 Amplifier Service Manual

Q43244-5 Control Module (P10405-2 board) Parts List

Capacitors Resistors
C700 C800 C 8426-6 .1µF 250V R700 R800 A10266-3622 3.6K .5W
C701 C801 C 8426-6 .1µF 250V R701 R801 A10266-1812 180 .5W
C900 C 8963-8 .47µF 250V R702 R802 A10266-3622 3.6K .5W
C901 C 8963-8 .47µF 250V R703 R803 A10266-3622 3.6K .5W
R900 A10266-2722 2.7K .5W
R901 A10266-1021 1.5K .5W
Diodes R902 C 7669-2 300 10W
D700 D800 C 3181-2 1N4148 R903 C 7669-2 300 10W
D900 C 2851-1 1N4004 R904 A10266-3902 39 .5W
R905 A10266-3602 36 .5W

Relays
K1 C 7860-7 SPST ICs
U700 U800 C 7664-3 MOC3031 Optotriac
U901 C 7665-0 MOC3011 Optotriac
Transistors U902 C 7665-0 MOC3011 Optotriac
Q700 Q800 C 3625-8 PNP 2N4125
Q701 Q801 C 7663-5 Triac MAC224A4
Q900 C 3625-8 PNP 2N4125 Misc.
Q901 C 3625-8 PNP 2N4125 Board P10405-2
Q902 C 3625-8 PNP 2N4125 J900 C 7672-6 8 Pin MTA Header
Tab Terminal C 7817-7 W1-W3, W100-W102
W200-W202
0 Ohm Jmp C 5868-2

22
 Com-Tech 200 Amplifier Service Manual

Q43242-9 Control Module (P10405-2 board) Parts List

Capacitors Resistors
C700 C800 C 8426-6 .1µF 250V R700 R800 A10266-3622 3.6K .5W
C701 C801 C 8426-6 .1µF 250V R701 R801 A10266-1812 180 .5W
C900 C 8963-8 .47µF 250V R702 R802 A10266-3622 3.6K .5W
C901 C 8963-8 .47µF 250V R703 R803 A10266-3622 3.6K .5W
R900 A10266-2722 2.7K .5W
R901 A10266-1021 1.5K .5W
Diodes R902 C 7669-2 300 10W
D700 D800 C 3181-2 1N4148 R903 C 7669-2 300 10W
D900 C 2851-1 1N4004 R904 A10266-3902 39 .5W
R905 A10266-3602 36 .5W

Relays
K1 C 7860-7 SPST ICs
U700 U800 C 7664-3 MOC3031 Optotriac
U901 C 7665-0 MOC3011 Optotriac
Transistors U902 C 7665-0 MOC3011 Optotriac
Q700 Q800 C 3625-8 PNP 2N4125
Q701 Q801 C 7663-5 Triac MAC224A4
Q900 C 3625-8 PNP 2N4125 Misc.
Q901 C 3625-8 PNP 2N4125 Board P10405-2
Q902 C 3625-8 PNP 2N4125 J900 C 7672-6 8 Pin MTA Header
J901 C 7873-0 2 Pin MTA Header
Tab Terminal C 7817-7 W1-W3, W100-W102
W200-W202
0 Ohm Jmp C 5868-2

23
 Com-Tech 200 Amplifier Service Manual

Q42706-4 Display Module (D 7083-5 board) Parts List

Capacitors Integrated Circuits
C500 C600 C 6802-0 .47µF 50V U903 C 4345-2 LMT339
C901 C 6804-6 .1µF 50V U904 C 7661-9 LM358N
U905 C 4345-2 LMT339
Diodes
D500 D600 C 3181-2 1N4148 Misc.
D501 D601 C 3181-2 1N4148 Board D 7083-5
D900 C 3533-4 1N966B 16V Zener IC Socket C 4508-5 16 Pin
D901 C 3533-4 1N966B 16V Zener LED Spacer C 7712-0
Cable H42913-6 8 Cond 24AWG
LED's Ribbon Cable
E500 E600 C 7863-1 Green with Connector
E501 E601 C 4431-0 Yellow
E502 E602 C 7863-1 Green
E900 C 4342-9 Amber

Transistors
Q500 Q600 C 3625-8 2N4125
Q501 Q601 C 3625-8 2N4125
Q502 Q602 C 7458-0 2N4123
Q503 Q603 C 3625-8 2N4125

Resistors
R500 R600 A10266-1031 10K
R501 R601 A10266-2221 2.2K
R502 R602 A10266-1051 1M
R503 R603 A102662751 2.7M
R504 R604 A10266-2032 20K .5W
R505 R605 A10266-2221 2.2K
R506 R606 A10266-4751 4.7M
R507 R607 A10266-2221 2.2K
R508 R608 A10266-1021 1K
R905 A10266-5141 510K
R906 A10266-2721 2.7K
R907 A10266-5141 510K
R908 A10266-3931 39K
R909 A10266-3931 39K
R910 A10266-4741 470K
R911 A10266-3931 39K
R912 A10266-1041 100K
R913 A10266-1031 10K
R914 A10266-8211 820
R915 A10266-3931 39K
R916 A10266-3631 36K
R917 A10266-8211 820
R918 A10266-3931 39K

24
 Com-Tech 200 Amplifier Service Manual

Q42716-3 Output Module (P10233-8 or P10263-5 board) Parts List

Capacitors Resistors
C01 C 3978-1 .047µF R00 C 2626-7 470
C02 C 2938-6 .1µF R01 C 2872-7 100
C03 C 2938-6 .1µF R02 C 3299-2 5.6 .5W
C04 C 6806-1 .01µF R04 C 6486-2 .2 5W
C05 C 6806-1 .01µF R07 C 6486-2 .2 5W
C06 C 6806-1 .01µF R09 C 4479-9 22
C07 C 6807-9 .001µF R10 C 2872-7 100
C08 C 6809-5 220pF R11 C 7317-8 2.7 5W
C09 C 6850-7 180pF R12 C 1001-4 2.7 1W
R13 C 2626-7 470
R16 C 6486-2 .2 5W
Diodes R19 C 6486-2 .2 5W
D01 C 2851-1 1N4004 R21 C 3299-2 5.6 .5W
D02 C 2851-1 1N4004 R22 C 4479-9 22
D03 C 2851-1 1N4004 R23 C 6844-2 250 Pot LS Bias
D04 C 2851-1 1N4004 R24 C 4300-7 13K
D05 C 2851-1 1N4004 R25 C 2628-3 2.2K
D06 C 2851-1 1N4004 R26 C 6844-2 250 Pot HS Bias
D07 C 2851-1 1N4004 R27 C 6495-3 390
D08 C 2851-1 1N4004 R28 C 4300-7 13K
D09 C 2851-1 1N4004 R30* C 6626-3* 102*
D10 C 2851-1 1N4004
D11 C 2851-1 1N4004
D12 C 2851-1 1N4004 Misc.
Board P10233-8 or P10263-5
Jumpers C 5868-2 0 Ohm .25W
Inductors J500 J600 C 7057-0 10 Pin Header
L00 C 6592-6 1.3µH Output Coil
L01 C 3510-2 470µH
L02 C 3510-2 470µH *Note: R30 is 102 Ohms in most units, though in some
cases a different value may be used to match the
installed S100/S200 LM334 (C5826-0) device grade.
Transistors This is the standard value and is used with the most
Q17 C 7271-7 NPN MPSU10 common LM334 grade, green. If the LM334 is marked
Q19 C 7318-6 PNP MPSU60 with a blue dot, R30 should be a 107 Ohm resistor
(A10265-10701); if it is marked with a yellow dot then
Note: Q18, S100, Driver Transistors, and Output Tran- R30 should be a 100 Ohm resistor (A10265-10001).
sistors are not included with Output Module. See
Output Assembly parts list for these part numbers.

25
 Com-Tech 200 Amplifier Service Manual

Q42888-0 Output Module (P10315-3 board) Parts List

Capacitors Resistors
C01 C 8511-5 .047µF 250V Ax R00 C 2626-7 470
C02 C 8426-6 .1µF R01 C 2872-7 100
C03 C 8426-6 .1µF R02 C 7778-1 5.6 .5W Flame Proof
C04 C 6805-3 .022µF R04 C 6486-2 .2 5W
C05 C 6805-3 .022µF R07 C 6486-2 .2 5W
C06 C 6806-1 .01µF 100V Ax R09 C 7779-9 22 Flame Proof
C07 C 6807-9 .001µF 100V Ax R10 C 2872-7 100
C08 C 6809-5 220pF R11 C 7317-8 2.7 5W
C09 C 6810-3 180pF R12 C 1001-4 2.7 1W
R13 C 2626-7 470
R16 C 6486-2 .2 5W
Diodes R19 C 6486-2 .2 5W
D01 C 2851-1 1N4004 R21 C 7778-1 5.6 .5W Flame Proof
D02 C 2851-1 1N4004 R22 C 7779-9 22 Flame Proof
D03 C 2851-1 1N4004 R23 C 6844-2 250 Pot LS Bias
D04 C 2851-1 1N4004 R24 C 4300-7 13K
D05 C 2851-1 1N4004 R25 C 2628-3 2.2K
D06 C 2851-1 1N4004 R26 C 6844-2 250 Pot HS Bias
D07 C 2851-1 1N4004 R27 C 6495-3 390
D08 C 2851-1 1N4004 R28 C 4300-7 13K
D09 C 2851-1 1N4004 R30* C 6626-3* 102*
D10 C 2851-1 1N4004
D11 C 2851-1 1N4004
D12 C 2851-1 1N4004 Misc.
Board P10315-3
Jumpers C 5868-2 0 Ohm .25W
Inductors Clips D 6414-3 Q17/Q19 Hold Down
L00 C 6592-6 1.3µH Output Coil J500 J600 C 7057-0 10 Pin Header
L01 C 3510-2 470µH
L02 C 3510-2 470µH
*Note: R30 is 102 Ohms in most units, though in some
cases a different value may be used to match the
Transistors installed S100/S200 LM334 (C5826-0) device grade.
Q17 C 8508-1 NPN 2SC3298B This is the standard value and is used with the most
Q19 C 8509-9 PNP 2SA1306B common LM334 grade, green. If the LM334 is marked
with a blue dot, R30 should be a 107 Ohm resistor
Note: Q18, S100, Driver Transistors, and Output Tran- (A10265-10701); if it is marked with a yellow dot then
sistors are not included with Output Module. See R30 should be a 100 Ohm resistor (A10265-10001).
Output Assembly parts list for part numbers.

26
 Com-Tech 200 Amplifier Service Manual

Q42969-8 Output Module (P10337-7 board) Parts List

Capacitors Resistors
C01 C 8511-5 .047µF 250V Ax R00 A10266-4711 470
C02 C 8426-6 .1µF R01 A10266-1011 100
C03 C 8426-6 .1µF R04 C 6486-2 .2 5W
C04 C 6805-3 .022µF R07 C 6486-2 .2 5W
C05 C 6805-3 .022µF R10 A10266-1011 100
C06 C 6806-1 .01µF 100V Ax R11 A10266-2R73 2.7 1W
C07 C 6807-9 .001µF 100V Ax R12 A10266-2R73 2.7 1W
C08 C 6810-3 180pF R13 A10266-4711 470
C09 C 6809-5 220pF R14 A10266-2R73 2.7 1W
C10 C 7697-3 .01µF R16 C 6486-2 .2 5W
C11 C 7697-3 .01µF R19 C 6486-2 .2 5W
C43 C 7697-3 .01µF R23 C 6844-2 250 Pot LS Bias
R24 A10266-1331 13K
R25 A10266-2221 2.2K
Diodes R26 C 6844-2 250 Pot HS Bias
D01 C 2851-1 1N4004 R27 A10266-3911 390
D02 C 2851-1 1N4004 R28 A10266-1331 13K
D03 C 2851-1 1N4004 R29 A10266-5101 51
D04 C 2851-1 1N4004 R30* A10265-10201* 102*
D05 C 2851-1 1N4004 R31 C 3614-2 15 .5W Flame Proof
D06 C 2851-1 1N4004 R32 C 3614-2 15 .5W Flame Proof
D07 C 2851-1 1N4004 R33 C 7779-9 22 .5W Flame Proof
D08 C 2851-1 1N4004 R34 C 7779-9 22 .5W Flame Proof
D09 C 2851-1 1N4004
D10 C 2851-1 1N4004
D11 C 2851-1 1N4004 Misc.
D12 C 2851-1 1N4004 Board P10337-7
Jumpers C 5868-2 0 Ohm .25W
Clips D 6414-3 Q17/Q19 Hold Down
Inductors J500 J600 C 7057-0 10 Pin Header
L00 C 6592-6 1.3µH Output Coil
L01 C 3510-2 470µH
L02 C 3510-2 470µH *Note: R30 is 102 Ohms in most units, though in some
cases a different value may be used to match the
installed S100/S200 LM334 (C5826-0) device grade.
Transistors This is the standard value and is used with the most
Q17 C 8508-1 NPN 2SC3298B common LM334 grade, green. If the LM334 is marked
Q19 C 8509-9 PNP 2SA1306B with a blue dot, R30 should be a 107 Ohm resistor
(A10265-10701); if it is marked with a yellow dot then
Note: Q18, S100, Driver Transistors, and Output Tran- R30 should be a 100 Ohm resistor (A10265-10001).
sistors are not included with the Output Module. See
Output Assembly parts list for part numbers.

27
 Com-Tech 200 Amplifier Service Manual

Q43188-4 Output Module (P10396-3 board) Parts List Cont.

Capacitors Resistors
C01 C 8511-5 .047µF 250V Ax R00 A10266-4711 470
C02 C 8426-6 .1µF R01 A10266-1011 100
C03 C 8426-6 .1µF R04 C 6486-2 .2 5W
C04 C 6805-3 .022µF R07 C 6486-2 .2 5W
C05 C 6805-3 .022µF R10 A10266-1011 100
C06 C 6806-1 .01µF 100V Ax R11 A10266-2R73 2.7 1W
C07 C 6807-9 .001µF 100V Ax R12 A10266-2R73 2.7 1W
C08 C 6810-3 180pF R13 A10266-4711 470
C09 C 6809-5 220pF R14 A10266-2R73 2.7 1W
C43 C 7697-3 .01µF Disc R16 C 6486-2 .2 5W
R19 C 6486-2 .2 5W
R23 C 6844-2 250 Pot LS Bias
Diodes R24 A10266-1331 13K
D01 C 2851-1 1N4004 R25 A10266-2221 2.2K
D02 C 2851-1 1N4004 R26 C 6844-2 250 Pot HS Bias
D03 C 2851-1 1N4004 R27 A10266-3911 390
D04 C 2851-1 1N4004 R28 A10266-1331 13K
D05 C 2851-1 1N4004 R29 A10266-5101 51
D06 C 2851-1 1N4004 R30* A10265-10201* 102* 1%
D07 C 2851-1 1N4004 R31 C 3614-2 15 .5W
D08 C 2851-1 1N4004 R32 C 3614-2 15 .5W
D09 C 2851-1 1N4004 R33 C 7779-9 22 .5W Flame Proof
D10 C 2851-1 1N4004 R34 C 7779-9 22 .5W Flame Proof
D11 C 2851-1 1N4004
D12 C 2851-1 1N4004
Misc.
Board P10396-3
Inductors Z1-Z7, Z9 C 5868-2 0 Ohm Jumper
L00 C 6592-6 1.3µH Output Coil Z8 A10124-24 Solid Wire
L01 C 3510-2 470µH Clips D 6414-3 Q17/Q19 Hold Down
L02 C 3510-2 470µH J500 J600 C 7057-0 10 Pin Header

Transistors *Note: R30 is 102 Ohms in most units, though in some

Q17 C10155-7 NPN 2SC4793 cases a different value may be used to match the
Q19 C10156-5 PNP 2SA1837 installed S100/S200 LM334 (C5826-0) device grade.
This is the standard value and is used with the most
Note: Q18, S100, Driver Transistors, and Output Tran- common LM334 grade, green. If the LM334 is marked
sistors are not included with Output Module. See with a blue dot, R30 should be a 107 Ohm resistor
Output Assembly parts list for part numbers. (A10265-10701); if it is marked with a yellow dot then
R30 should be a 100 Ohm resistor (A10265-10001).

28
 Com-Tech 200 Amplifier Service Manual

Q43013-4 Main Module (D 7911-7 board) Parts List

Capacitors C155 C255 C 6804-6 .1µF
C1 C 4303-1 1000µF C156 C256 C 6804-6 .1µF
C2 C 3913-8 470µF C157 C257 C 6806-1 .01µF
C4 C 6802-0 .47µF
C5 A10124-24 Jumper Wire
C6 A10124-24 Jumper Wire Diodes
C7 C 8897-8 .1µF D1 C 2851-1 1N4004
C100 C200 C 5311-3 22µF D2 C 2851-1 1N4004
C101 C201 C 2821-4 10pF D3 C 2851-1 1N4004
C103 C203 C 6805-3 .022µF D4 C 2851-1 1N4004
C104 C204 C 6805-3 .022µF D5 C 2851-1 1N4004
C105 C205 C 6812-9 47pF D6 C 2851-1 1N4004
C106 C206 C 6812-9 47pF D7 C 2851-1 1N4004
C107 C207 C 6804-6 .1µF D108 D208 C 3181-2 1N4148
C108 C208 C 6814-5 12pF D109 D209 C 3181-2 1N4148
C109 C209 C 7417-6 .0033µF D110 D210 C 3181-2 1N4148
C110 C210 C 5362-6 2.2µF D111 D211 C 5061-4 1N3070
C111 C211 C 6804-6 .1µF D112 D212 C 3181-2 1N4148
C112 C212 C 6803-8 .12µF D113 D213 C 3181-2 1N4148
C113 C213 C 6802-0 .47µF D120 D220 C 3181-2 1N4148
C114 C214 C 8854-9 100µF D121 D221 C 3181-2 1N4148
C115 C215 C 8854-9 100µF D122 D222 C 3181-2 1N4148
C116 C216 C 6802-0 .47µF D123 D223 C 5061-4 1N3070
C117 C217 C 6803-8 .12µF D124 D224 C 3181-2 1N4148
C118 C218 C 6814-5 12pF D125 D225 C 3181-2 1N4148
C119 C219 C 6802-0 .47µF D126 D226 C 5061-4 1N3070
C120 C220 C 6804-6 .1µF D127 D227 C 5061-4 1N3070
C122 C222 C 6811-1 100pF D128 D228 C 5061-4 1N3070
C123 C223 C 6812-9 47pF D129 D229 C 3181-2 1N4148
C124 C224 C 6812-9 47pF D130 D230 C 3181-2 1N4148
C129 C229 C 6814-5 12pF D131 D231 C 3181-2 1N4148
C130 C230 C 6813-7 27pF D132 D232 C 3181-2 1N4148
C133 C233 C 6813-7 27pF
C134 C234 C 6805-3 .022µF
C135 C235 C 6805-3 .022µF Transistors
C136 C236 C 6808-7 470pF Q100 Q200 D 2961-7 NPN 2N3859A
C137 C237 C 6808-7 470pF Q101 Q201 C 3578-9 PNP MPSA93
C138 C238 C 6813-7 27pF Q102 Q202 C 3810-6 NPN MPSA43
C139 C239 C 6813-7 27pF Q103 Q203 C 3786-8 PNP PN4250
C140 C240 C 6812-9 47pF Q105 Q205 C 3578-9 PNP MPSA93
C141 C241 C 6812-9 47pF Q106 Q206 C 3625-8 NPN 2N4125
C144 C244 C 8576-8 100µF Q107 Q207 C 3786-8 PNP PN4250
C145 C245 C 6812-9 47pF Q108 Q208 D 2961-7 NPN 2N3859A
C146 C246 C 6812-9 47pF Q109 Q209 D 2961-7 NPN 2N3859A
C147 C247 C 6806-1 .01µF Q110 Q210 C 3810-6 NPN MPSA43
C148 C248 C 6810-3 180pF Q112 Q212 C 3625-8 NPN 2N4125
C149 C249 C 6808-7 470pF Q113 Q213 C 3625-8 NPN 2N4125
C150 C250 C 6806-1 .01µF Q115 Q215 D 2962-5 NPN MPS8097
C151 C251 C 6806-1 .01µF Q116 Q216 C 3786-8 PNP PN4250
C152 C252 C 6950-7 82pF 5% Q117 Q217 D 2961-7 NPN 2N3859A
C153 C253 C 6804-6 .1µF Q118 Q218 D 2961-7 NPN 2N3859A
C154 C254 C 8426-6 .1µF 250V Q119 Q219 C 3625-8 NPN 2N4125

29
 Com-Tech 200 Amplifier Service Manual

Q43013-4 Main Module (D 7911-7 board) Parts List

Q120 Q220 C 3625-8 NPN 2N4125 R130 R230 A10266-1041 100K
Q121 Q221 C 7458-0 NPN 2N4123 R131 R231 A10266-1031 10K
Q122 Q222 C 7458-0 NPN 2N4123 R132 R232 C 5062-2 100K Pot (+ODEP)
Q123 Q223 C 7458-0 NPN 2N4123 R133 R233 A10266-2741 270K
Q124 Q224 C 3625-8 NPN 2N4125 R134 R234 A10266-2032 20K .5W
R135 R235 C 7782-3 100 Flame Proof
R136 R236 A10266-6821 6.8K
Resistors (.25W 5% unless R137 R237 C 7782-3 100 Flame Proof
noted otherwise) R138 R238 A10266-6821 6.8K
N100 N200 D 4669-4 Resistor Network R139 R239 A10266-8211 820
N101 N201 D 6081-0 Resistor Network R140 R240 A10266-6801 68
N102 N202 D 6082-8 Resistor Network R141 R241 A10266-1541 150K
R1 A10265-53621 53.6K 1% R142 R242 A10266-1541 150K
R2 OPEN R143 R243 A10266-1041 100K
R3 OPEN R144 R244 A10266-1041 100K
R4 A10265-46421 46.4K 1% R145 R245 A10266-1851 1.8M
R7 A10266-1041 100K R146 R246 A10266-1031 10K
R8 A10266-2031 20K R147 R247 C 7781-5 200 .5W Flame Proof
R9 A10266-5121 5.1K R148 R248 A10266-2721 2.7K
R16 A10266-5121 5.1K R149 R249 C 7781-5 200 .5W Flame Proof
R17 A10266-2031 20K R150 R250 A10266-2721 2.7K
R18 A10266-1041 100K R151 R251 A10266-1031 10K
R100 R200 C 7409-3 5K Linear Pot R152 R252 A10266-1231 12K
R101 R201 A10265-49911 4.99K 1% R153 R253 JUMPER A10124-24
R102 R202 A10266-5111 510 R154 R254 A10265-12131 121K 1%
R103 R203 A10265-10031 100K 1% R155 R255 A10266-1321 1.3K
R104 R204 A10266-2721 2.7K R156 R256 A10266-1321 1.3K
R105 R205 A10266-2721 2.7K R157 R257 A10266-1321 1.3K
R106 R206 A10266-1231 12K R158 R258 A10266-9121 9.1K
R107 R207 A10266-6831 68K R159 R259 A10266-1021 1K
R108 R208 A10266-8211 820 R160 R260 C 8260-9 10K 0.1%
R109 R209 A10266-6801 68 R161 R261 A10266-4701 47
R110 R210 A10266-6831 68K R162 R262 A10266-4701 47
R111 R211 A10266-1231 12K R163 R263 A10265-12131 121K 1%
R112 R212 A10266-5131 51K R164 R264 A10265-10021 10K 1%
R113 R213 A10266-4721 4.7K R165 R265 A10265-12131 121K 1%
R114 R214 A10266-4721 4.7K R166 R266 A10266-1851 1.8M
R115 R215 A10266-5141 510K R167 R267 A10265-10011 1K 1%
R116 R216 A10266-2751 2.7M R168 R268 A10265-95301 953 1%
R117 R217 A10266-4731 47K R170 R270 A10265-10011 1K 1%
R118 R218 A10266-2711 270 R171 R271 A10265-95301 953 1%
R119 R219 A10266-3911 390 R173 R273 A10265-10021 10K 1%
R120 R220 A10266-2711 270 R174 R274 A10265-24921 24.9K 1%
R121 R221 C 5062-2 100K Pot (-ODEP) R175 R275 A10265-28721 28.7K 1%
R122 R222 A10266-2741 270K R176 R276 A10265-24921 24.9K 1%
R123 R223 A10266-2032 20K .5W R177 R277 A10265-69811 6.98K 1%
R124 R224 A10266-6821 6.8K R179 R279 A10266-1321 1.3K
R125 R225 C 7782-3 100 Flame Proof R180 R280 A10266-4711 470
R126 R226 C 7782-3 100 Flame Proof R181 R281 A10266-4721 4.7K
R127 R227 A10266-6821 6.8K R182 R282 A10266-2201 22
R128 R228 A10266-1031 10K R183 R283 A10266-2421 2.4K
R129 R229 A10266-1041 100K R184 R284 A10266-4741 470K

30
 Com-Tech 200 Amplifier Service Manual

Q43013-4 Main Module (D 7911-7 board) Parts List

R185 R285 A10266-2421 2.4K Switches
R186 R286 A10266-2751 2.7M S2 OPEN
R187 R287 A10266-3631 36K S3 C 7960-5 Sensitivity
R188 R288 A10266-3631 36K S4 C 6781-6 Switch, Stereo/Mono
R189 R289 A10266-2731 27K
R190 R290 A10266-2051 2M
R191 R291 A10266-3331 33K IC’s
R192 R292 A10266-1031 10K U1 C 5095-2 UA7815
R193 R293 A10266-1031 10K U2 C 5096-0 UA7915
R194 R294 A10266-1041 100K U100 U200 C 6911-9 UPA75
R195 R295 A10266-3021 3K U101 U201 C 4345-2 LM339
R196 R296 A10266-4721 4.7K U102 U202 C 4345-2 LM339
R197 R297 A10266-1031 10K U103 U203 C 6910-1 UPA76
R198 R298 A10266-4721 4.7K U104 U204 C 7558-7 MC33079P
R199 R299 A10266-1031 10K
R906 R1006 OPEN
R907 R1007 OPEN
R908 R1008 OPEN
Misc.
R909 R1009 A10266-4741 470K Board D 7911-7
R910 R1010 A10266-4741 470K Socket C 3450-1 14 Pin (Qty 6)
R911 R1011 A10266-1521 1.5K Nut A10102-5 Hex 6-32 (Qty 2)
R912 R1012 A10266-4711 470 Heatsink C 5341-0 TO-220 (Qty 2)
R913 R1013 A10266-1051 1M Torq Spreader C 6541-4 (Qty 2)
R914 R1014 A10266-1051 1M Washer A10096-5 #6, Split (Qty 2)
R915 R1015 A10266-2201 22 Screw A10240-0608 Stainless (Qty 2)
R916 R1016 A10266-2201 22 J1 C 7593-4 5 Pin Header
J2 C 4508-5 16 Pin Socket
J3 C 7526-4 3 Pin Header
J100 J200 OPEN
J500 J800 D 6619-7 10 Inch Ribbon
J600 J700 D 6620-5 6 Inch Ribbon
Cable Tie C 1811-6 (Qty 4)

31
 Com-Tech 200 Amplifier Service Manual

Q43044-9 Main Module (D 7993-5 board) Parts List

Capacitors C155 C255 C 8897-8 .1µF
C1 C 4303-1 1000µF C156 C256 C 8897-8 .1µF
C2 C 3913-8 470µF C157 C257 C 6806-1 .01µF
C4 C 6802-0 .47µF
C5 A10124-24 Jumper Wire
C6 A10124-24 Jumper Wire Diodes
C7 C 8897-8 .1µF D1 C 2851-1 1N4004
C100 C200 C 5311-3 22µF D2 C 2851-1 1N4004
C101 C201 C 2821-4 10pF D3 C 2851-1 1N4004
C103 C203 C 6805-3 .022µF D4 C 2851-1 1N4004
C104 C204 C 6805-3 .022µF D5 C 2851-1 1N4004
C105 C205 C 6812-9 47pF D6 C 2851-1 1N4004
C106 C206 C 6812-9 47pF D7 C 2851-1 1N4004
C107 C207 C 8897-8 .1µF D108 D208 C 3181-2 1N4148
C108 C208 C 6814-5 12pF D109 D209 C 3181-2 1N4148
C109 C209 C 7417-6 .0033µF D110 D210 C 3181-2 1N4148
C110 C210 C 5362-6 2.2µF D111 D211 C 5061-4 1N3070
C111 C211 C 8897-8 .1µF D112 D212 C 3181-2 1N4148
C112 C212 C 8991-9 .47µF D113 D213 C 3181-2 1N4148
C113 C213 C 8987-7 22µF D114 D214 OPEN
C114 C214 C 8854-9 100µF D115 D215 OPEN
C115 C215 C 8854-9 100µF D120 D220 C 3181-2 1N4148
C116 C216 C 8987-7 22µF D121 D221 C 3181-2 1N4148
C117 C217 C 8991-9 .47µF D122 D222 C 3181-2 1N4148
C118 C218 C 6814-5 12pF D123 D223 C 5061-4 1N3070
C119 C219 C 6802-0 .47µF D124 D224 C 3181-2 1N4148
C120 C220 C 8897-8 .1µF D125 D225 C 3181-2 1N4148
C122 C222 C 6811-1 100pF D126 D226 C 5061-4 1N3070
C123 C223 C 6812-9 47pF D127 D227 C 5061-4 1N3070
C124 C224 C 6812-9 47pF D128 D228 C 5061-4 1N3070
C129 C229 C 6814-5 12pF D129 D229 C 3181-2 1N4148
C130 C230 C 6813-7 27pF D130 D230 C 3181-2 1N4148
C133 C233 C 6813-7 27pF D131 D231 C 3181-2 1N4148
C134 C234 C 6805-3 .022µF D132 D232 C 3181-2 1N4148
C135 C235 C 6805-3 .022µF
C136 C236 C 6808-7 470pF
C137 C237 C 6808-7 470pF Transistors
C138 C238 C 6813-7 27pF Q100 Q200 D 2961-7 NPN 2N3859A
C139 C239 C 6813-7 27pF Q101 Q201 C 3578-9 PNP MPSA93
C140 C240 C 6812-9 47pF Q102 Q202 C 3810-6 NPN MPSA43
C141 C241 C 6812-9 47pF Q103 Q203 C 3786-8 PNP PN4250
C144 C244 C 8576-8 100µF Q105 Q205 C 3578-9 PNP MPSA93
C145 C245 C 6812-9 47pF Q106 Q206 C 3625-8 NPN 2N4125
C146 C246 C 6812-9 47pF Q107 Q207 C 3786-8 PNP PN4250
C147 C247 C 6806-1 .01µF Q108 Q208 D 2961-7 NPN 2N3859A
C148 C248 C 6810-3 180pF Q109 Q209 D 2961-7 NPN 2N3859A
C149 C249 C 6808-7 470pF Q110 Q210 C 3810-6 NPN MPSA43
C150 C250 C 6806-1 .01µF Q112 Q212 C 3625-8 NPN 2N4125
C151 C251 C 6806-1 .01µF Q113 Q213 C 3625-8 NPN 2N4125
C152 C252 C 6950-7 82pF 5% Q115 Q215 D 2962-5 NPN MPS8097
C153 C253 C 8897-8 .1µF Q116 Q216 C 3786-8 PNP PN4250
C154 C254 C 8426-6 .1µF 250V Q117 Q217 D 2961-7 NPN 2N3859A

32
 Com-Tech 200 Amplifier Service Manual

Q43044-9 Main Module (D 7993-5 board) Parts List

Q118 Q218 D 2961-7 NPN 2N3859A R128 R228 A10266-1031 10K
Q119 Q219 C 3625-8 NPN 2N4125 R129 R229 A10266-1041 100K
Q120 Q220 C 3625-8 NPN 2N4125 R130 R230 A10266-1041 100K
Q121 Q221 C 7458-0 NPN 2N4123 R131 R231 A10266-1031 10K
Q122 Q222 C 7458-0 NPN 2N4123 R132 R232 C 5062-2 100K Pot (+ODEP)
Q123 Q223 C 7458-0 NPN 2N4123 R133 R233 A10266-2741 270K
Q124 Q224 C 3625-8 NPN 2N4125 R134 R234 A10266-2032 20K .5W
R135 R235 C 7782-3 100 Flame Proof
R136 R236 A10266-6821 6.8K
Resistors (.25W 5% unless R137 R237 C 7782-3 100 Flame Proof
noted otherwise) R138 R238 A10266-6821 6.8K
N101 N201 D 7945-5 Resistor Network R139 R239 A10266-8211 820
N102 N202 D 6082-8 Resistor Network R140 R240 A10266-6801 68
R1 A10265-53621 53.6K 1% R141 R241 A10266-1541 150K
R2 OPEN R142 R242 A10266-1541 150K
R3 OPEN R143 R243 A10266-1041 100K
R4 A10265-46421 46.4K 1% R144 R244 A10266-1041 100K
R7 A10266-1041 100K R145 R245 A10266-1851 1.8M
R8 A10266-2031 20K R146 R246 A10266-1031 10K
R9 A10266-5121 5.1K R147 R247 C 7781-5 200 .5W Flame Proof
R10 OPEN R148 R248 A10266-2721 2.7K
R16 A10266-5121 5.1K R149 R249 C 7781-5 200 .5W Flame Proof
R17 A10266-2031 20K R150 R250 A10266-2721 2.7K
R18 A10266-1041 100K R151 R251 A10266-1031 10K
R100 R200 C 7409-3 5K Linear Pot R152 R252 A10265-11821 11.8K 1%
R101 R201 A10265-49911 4.99K 1% R153 R253 JUMPER A10124-24
R102 R202 A10266-5111 510 R154 R254 C 8261-7 121K 0.1%
R103 R203 A10265-10031 100K 1% R155 R255 A10266-1321 1.3K
R104 R204 A10266-2721 2.7K R156 R256 A10266-1321 1.3K
R105 R205 A10266-2721 2.7K R157 R257 A10266-1321 1.3K
R106 R206 A10266-1231 12K R158 R258 A10265-11321 11.3K 1%
R107 R207 A10266-6831 68K R159 R259 A10266-1021 1K
R108 R208 A10266-8211 820 R160 R260 C 8260-9 10K 0.1%
R109 R209 A10266-6801 68 R161 R261 A10266-4701 47
R110 R210 A10266-6831 68K R162 R262 A10266-4701 47
R111 R211 A10266-1231 12K R163 R263 C 8261-7 121K 0.1%
R112 R212 A10266-5131 51K R164 R264 C 8260-9 10K 0.1%
R113 R213 A10266-4721 4.7K R165 R265 C 8261-7 121K 0.1%
R114 R214 A10266-4721 4.7K R166 R266 A10266-1851 1.8M
R115 R215 A10266-5141 510K R167 R267 A10265-10011 1K 1%
R116 R216 A10266-2751 2.7M R168 R268 A10265-97601 976 1%
R117 R217 A10266-4731 47K R170 R270 A10265-10011 1K 1%
R118 R218 A10266-2711 270 R171 R271 A10265-95301 953 1%
R119 R219 A10266-3911 390 R173 R273 C 8260-9 10K 0.1%
R120 R220 A10266-2711 270 R174 R274 A10265-24921 24.9K 1%
R121 R221 C 5062-2 100K Pot (-ODEP) R175 R275 A10265-28721 28.7K 1%
R122 R222 A10266-2741 270K R176 R276 A10265-24921 24.9K 1%
R123 R223 A10266-2032 20K .5W R177 R277 A10265-69811 6.98K 1%
R124 R224 A10266-6821 6.8K R179 R279 A10266-1321 1.3K
R125 R225 C 7782-3 100 Flame Proof R180 R280 A10266-4711 470
R126 R226 C 7782-3 100 Flame Proof R181 R281 A10266-4721 4.7K
R127 R227 A10266-6821 6.8K R182 R282 A10266-2201 22

33
 Com-Tech 200 Amplifier Service Manual

Q43044-9 Main Module (D 7993-5 board) Parts List

R183 R283 A10266-2421 2.4K Switches
R184 R284 A10266-4741 470K S2 OPEN
R185 R285 A10266-2421 2.4K S3 C 7960-5 Sensitivity
R186 R286 A10266-2751 2.7M S4 C 6781-6 Switch, Stereo/Mono
R187 R287 A10266-3631 36K
R188 R288 A10266-3631 36K
R189 R289 A10266-2731 27K IC’s
R190 R290 A10266-2051 2M U1 C 5095-2 UA7815
R191 R291 A10266-3331 33K U2 C 5096-0 UA7915
R192 R292 A10266-1031 10K U100 U200 C 6911-9 UPA75
R193 R293 A10266-1031 10K U101 U201 C 4345-2 LM339
R194 R294 A10266-1041 100K U102 U202 C 4345-2 LM339
R195 R295 A10266-3021 3K U103 U203 C 6910-1 UPA76
R196 R296 A10266-4721 4.7K U104 U204 C 7558-7 MC33079P
R197 R297 A10266-1031 10K
R198 R298 A10266-4721 4.7K
R199 R299 A10266-1031 10K
R906 R1006 OPEN
Misc.
R907 R1007 OPEN Board D 7993-5
R908 R1008 OPEN Socket C 3450-1 14 Pin (Qty 6)
R909 R1009 A10266-4741 470K Nut A10102-5 Hex 6-32 (Qty 2)
R910 R1010 A10266-4741 470K Heatsink C 5341-0 TO-220 (Qty 2)
R911 R1011 A10266-1521 1.5K Torq Spreader C 6541-4 (Qty 2)
R912 R1012 A10266-4711 470 Washer A10096-5 #6, Split (Qty 2)
R913 R1013 A10266-1051 1M Screw A10240-0608 Stainless (Qty 2)
R914 R1014 A10266-1051 1M J1 C 7593-4 5 Pin Header
R915 R1015 A10266-2201 22 J2 C 4508-5 16 Pin Socket
R916 R1016 A10266-2201 22 J11 C 7526-4 3 Pin Header
R917 R1017 A10265-10021 10K 1% J100 J200 OPEN
R918 R1018 A10265-10021 10K 1% J500 J800 D 6619-7 10 Inch Ribbon
R919 R1019 A10265-10021 10K 1% J600 J700 D 6620-5 6 Inch Ribbon
R920 R1020 A10265-10021 10K 1% Cable Tie C 1811-6 (Qty 4)
R921 R1021 C 9079-2 200 Pot (CMR Null)

34
 Com-Tech 200 Amplifier Service Manual

Q43128-0 Main Module (D8283-0 board) Parts List

Capacitors C155 C255 C 8897-8 .1µF
C1 C 4303-1 1000µF C156 C256 C 8897-8 .1µF
C2 C 3913-8 470µF C157 C257 C 6806-1 .01µF
C4 C 6802-0 .47µF C158 C258 C 6807-9 .001µF
C5 A10124-24 Jumper Wire C159 C259 C 6807-9 .001µF
C6 A10124-24 Jumper Wire C160 C260 C 6811-1 100pF
C7 C 8897-8 .1µF C161 C261 C 6811-1 100pF
C100 C200 C 5311-3 22µF
C101 C201 C 9464-6 10pF Diodes
C103 C203 C 6805-3 .022µF D1 C 2851-1 1N4004
C104 C204 C 6805-3 .022µF D2 C 2851-1 1N4004
C105 C205 C 6812-9 47pF D3 C 2851-1 1N4004
C106 C206 C 6812-9 47pF D4 C 2851-1 1N4004
C107 C207 C 8897-8 .1µF D5 C 2851-1 1N4004
C108 C208 C 6814-5 12pF D6 C 2851-1 1N4004
C109 C209 C 7417-6 .0033µF D7 C 2851-1 1N4004
C110 C210 C 5362-6 2.2µF D108 D208 C 3181-2 1N4148
C111 C211 C 8897-8 .1µF D109 D209 C 3181-2 1N4148
C112 C212 C 8991-9 .47µF D110 D210 C 3181-2 1N4148
C113 C213 C 8987-7 22µF D111 D211 C 5061-4 1N3070
C114 C214 C 8854-9 100µF D112 D212 C 3181-2 1N4148
C115 C215 C 8854-9 100µF D113 D213 C 3181-2 1N4148
C116 C216 C 8987-7 22µF D114 D214 C 3181-2 1N4148
C117 C217 C 8991-9 .47µF D115 D215 C 3181-2 1N4148
C118 C218 C 6814-5 12pF D120 D220 C 3181-2 1N4148
C119 C219 C 6802-0 .47µF D121 D221 C 3181-2 1N4148
C120 C220 C 8897-8 .1µF D122 D222 C 3181-2 1N4148
C122 C222 C 6811-1 100pF D123 D223 C 5061-4 1N3070
C123 C223 C 6812-9 47pF D124 D224 C 3181-2 1N4148
C124 C224 C 6812-9 47pF D125 D225 C 3181-2 1N4148
C129 C229 C 6814-5 12pF D126 D226 C 5061-4 1N3070
C130 C230 C 6813-7 27pF D127 D227 C 5061-4 1N3070
C133 C233 C 6813-7 27pF D128 D228 C 5061-4 1N3070
C134 C234 C 6805-3 .022µF D129 D229 C 3181-2 1N4148
C135 C235 C 6805-3 .022µF D130 D230 C 3181-2 1N4148
C136 C236 C 6808-7 470pF D131 D231 C 3181-2 1N4148
C137 C237 C 6808-7 470pF D132 D232 C 3181-2 1N4148
C138 C238 C 6813-7 27pF D133 D233 C 3181-2 1N4148
C139 C239 C 6813-7 27pF D134 D234 C 3181-2 1N4148
C140 C240 C 6812-9 47pF
C141 C241 C 6812-9 47pF Transistors
C144 C244 C 8576-8 100µF Q100 Q200 D 2961-7 NPN 2N3859A
C145 C245 C 6812-9 47pF Q101 Q201 C 3578-9 PNP MPSA93
C146 C246 C 6812-9 47pF Q102 Q202 C 3810-6 NPN MPSA43
C147 C247 C 6806-1 .01µF Q103 Q203 C 3786-8 PNP PN4250
C148 C248 C 6810-3 180pF Q105 Q205 C 3578-9 PNP MPSA93
C149 C249 C 6808-7 470pF Q106 Q206 C 3625-8 NPN 2N4125
C150 C250 C 6806-1 .01µF Q107 Q207 C 3786-8 PNP PN4250
C151 C251 C 6806-1 .01µF Q108 Q208 C 5891-4 NPN MTS105
C152 C252 C 6950-7 82pF 5% Q109 Q209 D 2961-7 NPN 2N3859A
C153 C253 C 8897-8 .1µF Q110 Q210 C 3810-6 NPN MPSA43
C154 C254 C 8426-6 .1µF 250V Q112 Q212 C 3625-8 NPN 2N4125

35
 Com-Tech 200 Amplifier Service Manual

Q43128-0 Main Module (D8283-0 board) Parts List

Q113 Q213 C 3625-8 NPN 2N4125 R126 R226 C 7782-3 100 Flame Proof
Q115 Q215 D 2962-5 NPN MPS8097 R127 R227 A10266-6821 6.8K
Q116 Q216 C 3786-8 PNP PN4250 R128 R228 A10266-1331 13K
Q117 Q217 D 2961-7 NPN 2N3859A R129 R229 A10266-1041 100K
Q118 Q218 D 2961-7 NPN 2N3859A R130 R230 A10266-1041 100K
Q119 Q219 C 3625-8 NPN 2N4125 R131 R231 A10266-1331 13K
Q120 Q220 C 3625-8 NPN 2N4125 R132 R232 C 5062-2 100K Pot (+ODEP)
Q121 Q221 C 7458-0 NPN 2N4123 R133 R233 A10266-2741 270K
Q122 Q222 C 7458-0 NPN 2N4123 R134 R234 A10266-2032 20K .5W
Q123 Q223 C 7458-0 NPN 2N4123 R135 R235 C 7782-3 100 Flame Proof
Q124 Q224 C 3625-8 NPN 2N4125 R136 R236 A10266-6821 6.8K
Q125 Q225 C 3786-8 PNP PN4250A R137 R237 C 7782-3 100 Flame Proof
Q126 Q226 C 5891-4 NPN MTS105 R138 R238 A10266-6821 6.8K
R139 R239 A10266-8211 820
Resistors R140 R240 A10266-5601 56
R1 A10265-53621 53.6K 1% R141 R241 A10266-1541 150K
R2 OPEN R142 R242 A10266-1541 150K
R3 OPEN R143 R243 A10266-1041 100K
R4 A10265-46421 46.4K 1% R144 R244 A10266-1041 100K
R7 A10266-1041 100K R145 R245 A10266-2251 2.2M
R8 A10266-2031 20K R146 R246 A10266-1031 10K
R9 A10266-5121 5.1K R147 R247 C 7781-5 200 .5W Flame Proof
R10 OPEN R148 R248 A10266-2721 2.7K
R16 A10266-5121 5.1K R149 R249 C 7781-5 200 .5W Flame Proof
R17 A10266-2031 20K R150 R250 A10266-2721 2.7K
R18 A10266-1041 100K R151 R251 A10266-1031 10K
R100 R200 C 7409-3 5K Linear Pot R152 R252 A10265-11821 11.8K 1%
R101 R201 A10265-49911 4.99K 1% R153 R253 JUMPER A10124-24
R102 R202 A10266-5111 510 R154 R254 C 8261-7 121K 0.1%
R103 R203 A10265-10031 100K 1% R155 R255 A10266-1321 1.3K
R104 R204 A10266-2721 2.7K R156 R256 A10266-1321 1.3K
R105 R205 A10266-2721 2.7K R157 R257 A10266-1321 1.3K
R106 R206 A10266-1231 12K R158 R258 A10265-11521 11.5K 1%
R107 R207 A10266-6831 68K R159 R259 A10266-1021 1K
R108 R208 A10266-8211 820 R160 R260 C 8260-9 10K 0.1%
R109 R209 A10266-5601 56 R161 R261 A10266-4701 47
R110 R210 A10266-6831 68K R162 R262 A10266-4701 47
R111 R211 A10266-1231 12K R163 R263 C 8261-7 121K 0.1%
R112 R212 A10266-5131 51K R164 R264 C 8260-9 10K 0.1%
R113 R213 A10266-4721 4.7K R165 R265 C 8261-7 121K 0.1%
R114 R214 A10266-4721 4.7K R166 R266 A10266-2251 2.2M
R115 R215 A10266-5141 510K R167 R267 A10265-10011 1K 1%
R116 R216 A10266-2751 2.7M R168 R268 A10265-10011 1K 1%
R117 R217 A10266-4731 47K R170 R270 A10265-10011 1K 1%
R118 R218 A10265-27401 274 1% R171 R271 A10265-10011 1K 1%
R119 R219 A10265-66501 665 1% R173 R273 C 8260-9 10K 0.1%
R120 R220 A10265-28701 287 1% R174 R274 A10265-24921 24.9K 1%
R121 R221 C 5062-2 100K Pot (-ODEP) R175 R275 A10265-28721 28.7K 1%
R122 R222 A10266-2741 270K R176 R276 A10265-24921 24.9K 1%
R123 R223 A10266-2032 20K .5W R177 R277 A10265-69811 6.98K 1%
R124 R224 A10266-6821 6.8K R179 R279 A10266-1321 1.3K
R125 R225 C 7782-3 100 Flame Proof R180 R280 A10266-4711 470

36
 Com-Tech 200 Amplifier Service Manual

Q43128-0 Main Module (D8283-0 board) Parts List

R181 R281 A10266-4721 4.7K Switches
R182 R282 A10266-2201 22 S2 OPEN
R183 R283 A10266-2421 2.4K S3 C 7960-5 Sensitivity
R184 R284 A10266-4741 470K S4 C 6781-6 Switch, Stereo/Mono
R185 R285 A10266-2421 2.4K
R186 R286 A10266-2751 2.7M Integrated Circuits
R187 R287 A10266-3631 36K U1 C 5095-2 UA7815
R188 R288 A10266-3631 36K U2 C 5096-0 UA7915
R189 R289 A10266-2731 27K U100 U200 C 6911-9 UPA75
R190 R290 A10266-2051 2M U101 U201 C 4345-2 LM339
R191 R291 A10266-3331 33K U102 U202 C 4345-2 LM339
R192 R292 A10266-1031 10K U103 U203 C 6910-1 UPA76
R193 R293 A10266-1031 10K U104 U204 C 7558-7 MC33079P
R194 R294 A10266-1041 100K
R195 R295 A10266-3021 3K
R196 R296 A10266-4721 4.7K
Misc.
R197 R297 A10266-1031 10K Board D 8283-0
R198 R298 A10266-4721 4.7K Socket C 3450-1 14 Pin (Qty 6)
R199 R299 A10266-1031 10K Nut A10102-5 Hex 6-32 (Qty 2)
R906 R1006 OPEN Heatsink C 5341-0 TO-220 (Qty 2)
R907 R1007 OPEN Tq Spreader C 6541-4 (Qty 2)
R908 R1008 OPEN Washer A10096-5 #6, Split (Qty 2)
R909 R1009 A10266-4741 470K Screw A10240-0608 Stainless (Qty 2)
R910 R1010 A10266-4741 470K J1 C 7593-4 5 Pin Header
R911 R1011 A10266-1521 1.5K J2 C 4508-5 16 Pin Socket
R912 R1012 A10266-4711 470 J11 C 7526-4 3 Pin Header
R913 R1013 A10266-1051 1M J100 J200 OPEN
R914 R1014 A10266-1051 1M J500 J800 D 6619-7 10 Inch Ribbon
R915 R1015 A10266-2201 22 J600 J700 D 6620-5 6 Inch Ribbon
R916 R1016 A10266-2201 22 Cable Tie C 1811-6 (Qty 4)
R917 R1017 A10265-10021 10K 1% TP 1 C 9450-5 Header, 6 pin RT Ang
R918 R1018 A10265-10021 10K 1% Spacer C 9225-1 Plastic Spcr (Qty 5)
R919 R1019 A10265-10021 10K 1%
R920 R1020 A10265-10021 10K 1%
R921 R1021 C 9079-2 200 Pot (CMR Null)
R922 R1022 A10265-66501 665 1%
R923 R1023 A10265-35711 3.57K 1%
R924 R1024 A10265-66501 665 1%
R925 R1025 A10265-10031 100K 1%
R926 R1026 A10265-66501 665 1%
R927 R1027 A10265-10031 100K 1%
R928 R1028 A10265-35711 3.57K 1%
R929 R1029 A10266-1041 100K
R930 R1030 A10266-1041 100K

Resistor Networks
N101 N201 D 7945-5 Resistor Network
N102 N202 D 6082-8 Resistor Network

37
 Com-Tech 200 Amplifier Service Manual

Q43237-9 Main Module (D 8369-7 board) Parts List

Capacitors C155 C255 C 8897-8 .1µF
C1 C 9859-7 1000µF C156 C256 C 8897-8 .1µF
C2 C 9859-7 1000µF C157 C257 C 6806-1 .01µF
C4 C 6802-0 .47µF C158 C258 C 6805-3 .022µF
C5 A10124-24 Jumper Wire C159 C259 C 6805-3 .022µF
C6 A10124-24 Jumper Wire C160 C260 C 6811-1 100pF
C7 C 8897-8 .1µF C161 C261 C 6811-1 100pF
C100 C200 C 5311-3 22µF
C101 C201 C 9464-6 10pF Diodes
C103 C203 C 6805-3 .022µF D1 C 2851-1 1N4004
C104 C204 C 6805-3 .022µF D2 C 2851-1 1N4004
C105 C205 C 6812-9 47pF D3 C 2851-1 1N4004
C106 C206 C 6812-9 47pF D4 C 2851-1 1N4004
C107 C207 C 8897-8 .1µF D5 C 2851-1 1N4004
C108 C208 C 6814-5 12pF D6 C 2851-1 1N4004
C109 C209 C 7417-6 .0033µF D7 C 2851-1 1N4004
C110 C210 C 5362-6 2.2µF D108 D208 C 3181-2 1N4148
C111 C211 C 8897-8 .1µF D109 D209 C 3181-2 1N4148
C112 C212 C 8991-9 .47µF D110 D210 C 3181-2 1N4148
C113 C213 C 8987-7 22µF D111 D211 C 5061-4 1N3070
C114 C214 C 8854-9 100µF D112 D212 C 3181-2 1N4148
C115 C215 C 8854-9 100µF D113 D213 C 3181-2 1N4148
C116 C216 C 8987-7 22µF D114 D214 C 3181-2 1N4148
C117 C217 C 8991-9 .47µF D115 D215 C 3181-2 1N4148
C118 C218 C 6814-5 12pF D120 D220 C 3181-2 1N4148
C119 C219 C 6802-0 .47µF D121 D221 C 3181-2 1N4148
C120 C220 C 8897-8 .1µF D122 D222 C 3181-2 1N4148
C122 C222 C 6811-1 100pF D123 D223 C 5061-4 1N3070
C123 C223 C 6812-9 47pF D124 D224 C 3181-2 1N4148
C124 C224 C 6812-9 47pF D125 D225 C 3181-2 1N4148
C129 C229 C 6814-5 12pF D126 D226 C 5061-4 1N3070
C130 C230 C 6813-7 27pF D127 D227 C 5061-4 1N3070
C133 C233 C 6813-7 27pF D128 D228 C 5061-4 1N3070
C134 C234 C 6805-3 .022µF D129 D229 C 3181-2 1N4148
C135 C235 C 6805-3 .022µF D130 D230 C 3181-2 1N4148
C136 C236 C 6808-7 470pF D131 D231 C 3181-2 1N4148
C137 C237 C 6808-7 470pF D132 D232 C 3181-2 1N4148
C138 C238 C 6813-7 27pF D133 D233 C 3181-2 1N4148
C139 C239 C 6813-7 27pF D134 D234 C 3181-2 1N4148
C140 C240 C 6812-9 47pF
C141 C241 C 6812-9 47pF Transistors
C144 C244 C 8576-8 100µF Q100 Q200 D 2961-7 NPN 2N3859A
C145 C245 C 6812-9 47pF Q101 Q201 C 3578-9 PNP MPSA93
C146 C246 C 6812-9 47pF Q102 Q202 C 3810-6 NPN MPSA43
C147 C247 C 6806-1 .01µF Q103 Q203 C 3786-8 PNP PN4250
C148 C248 C 6810-3 180pF Q105 Q205 C 3578-9 PNP MPSA93
C149 C249 C 6808-7 470pF Q106 Q206 C 3625-8 NPN 2N4125
C150 C250 C 6806-1 .01µF Q107 Q207 C 3786-8 PNP PN4250
C151 C251 C 6806-1 .01µF Q108 Q208 C 5891-4 NPN MTS105
C152 C252 C 6950-7 82pF 5% Q109 Q209 D 2961-7 NPN 2N3859A
C153 C253 C 8897-8 .1µF Q110 Q210 C 3810-6 NPN MPSA43
C154 C254 A10434-104JD .1µF 250V Q112 Q212 C 3625-8 NPN 2N4125

38
 Com-Tech 200 Amplifier Service Manual

Q43237-9 Main Module (D 8369-7 board) Parts List

Q113 Q213 C 3625-8 NPN 2N4125 R126 R226 C 8836-6 100 .5W Flame Proof
Q115 Q215 D 2962-5 NPN MPS8097 R127 R227 A10266-6821 6.8K
Q116 Q216 C 3786-8 PNP PN4250 R128 R228 A10266-1331 13K
Q117 Q217 D 2961-7 NPN 2N3859A R129 R229 A10266-1041 100K
Q118 Q218 D 2961-7 NPN 2N3859A R130 R230 A10266-1041 100K
Q119 Q219 C 3625-8 NPN 2N4125 R131 R231 A10266-1331 13K
Q120 Q220 C 3625-8 NPN 2N4125 R132 R232 C 5062-2 100K Pot (+ODEP)
Q121 Q221 C 7458-0 NPN 2N4123 R133 R233 A10266-2741 270K
Q122 Q222 C 7458-0 NPN 2N4123 R134 R234 A10266-2032 20K .5W
Q123 Q223 C 7458-0 NPN 2N4123 R135 R235 C 8836-6 100 .5W Flame Proof
Q124 Q224 C 3625-8 NPN 2N4125 R136 R236 A10266-6821 6.8K
Q125 Q225 C 3786-8 PNP PN4250A R137 R237 C 8836-6 100 .5W Flame Proof
Q126 Q226 C 5891-4 NPN MTS105 R138 R238 A10266-6821 6.8K
R139 R239 A10266-8211 820
Resistors R140 R240 A10266-5601 56
R1 A10265-53621 53.6K 1% R141 R241 A10266-1541 150K
R2 OPEN R142 R242 A10266-1541 150K
R3 OPEN R143 R243 A10266-1041 100K
R4 A10265-46421 46.4K 1% R144 R244 A10266-1041 100K
R7 A10266-1041 100K R145 R245 A10266-3351 3.3M
R8 A10266-2031 20K R146 R246 A10266-1031 10K
R9 A10266-5121 5.1K R147 R247 C 7781-5 200 .5W Flame Proof
R10 OPEN R148 R248 A10266-2721 2.7K
R16 A10266-5121 5.1K R149 R249 C 7781-5 200 .5W Flame Proof
R17 A10266-2031 20K R150 R250 A10266-2721 2.7K
R18 A10266-1041 100K R151 R251 A10266-1031 10K
R100 R200 C 9785-4 5K Linear W/21 Det. R152 R252 A10265-11821 11.8K 1%
R101 R201 A10265-49911 4.99K 1% R153 R253 JUMPER A10124-24
R102 R202 A10266-5111 510 R154 R254 C 8261-7 121K 0.1%
R103 R203 A10265-10031 100K 1% R155 R255 A10266-1321 1.3K
R104 R204 A10266-2721 2.7K R156 R256 A10266-1321 1.3K
R105 R205 A10266-2721 2.7K R157 R257 A10266-1321 1.3K
R106 R206 A10266-1231 12K R158 R258 A10265-11521 11.5K 1%
R107 R207 A10266-6831 68K R159 R259 A10266-1021 1K
R108 R208 A10266-8211 820 R160 R260 C 8260-9 10K 0.1%
R109 R209 A10266-5601 56 R161 R261 A10266-4701 47
R110 R210 A10266-6831 68K R162 R262 A10266-4701 47
R111 R211 A10266-1231 12K R163 R263 C 8261-7 121K 0.1%
R112 R212 A10266-5131 51K R164 R264 C 8260-9 10K 0.1%
R113 R213 A10266-4721 4.7K R165 R265 C 8261-7 121K 0.1%
R114 R214 A10266-4721 4.7K R166 R266 A10266-3351 3.3M
R115 R215 A10266-3641 360K R167 R267 A10265-10011 1K 1%
R116 R216 A10266-2751 2.7M R168 R268 A10265-10011 1K 1%
R117 R217 A10266-4731 47K R170 R270 A10265-10011 1K 1%
R118 R218 A10265-27401 274 1% R171 R271 A10265-10011 1K 1%
R119 R219 A10265-66501 665 1% R173 R273 C 8260-9 10K 0.1%
R120 R220 A10265-28701 287 1% R174 R274 A10265-24921 24.9K 1%
R121 R221 C 5062-2 100K Pot (-ODEP) R175 R275 A10265-28721 28.7K 1%
R122 R222 A10266-2741 270K R176 R276 A10265-24921 24.9K 1%
R123 R223 A10266-2032 20K .5W R177 R277 A10265-69811 6.98K 1%
R124 R224 A10266-6821 6.8K R178 R278 A10266-2021 2K
R125 R225 C 8836-6 100 .5W Flame Proof R179 R279 A10266-1321 1.3K

39
 Com-Tech 200 Amplifier Service Manual

Q43237-9 Main Module (D 8369-7 board) Parts List

R180 R280 A10266-4711 470 Resistor Networks
R181 R281 A10266-4721 4.7K N101 N201 D 7945-5 Resistor Network
R182 R282 A10266-2201 22 N102 N202 D 6082-8 Resistor Network
R183 R283 A10266-2421 2.4K
R184 R284 A10266-4741 470K Switches
R185 R285 A10266-2421 2.4K S3 C 7960-5 Sensitivity
R186 R286 A10266-2751 2.7M S4 C 6781-6 Switch, Stereo/Mono
R187 R287 A10266-3631 36K
R188 R288 A10266-3631 36K
R189 R289 A10266-2731 27K
Integrated Circuits
R190 R290 A10266-2051 2M U1 C 5095-2 UA7815
R191 R291 A10266-1831 18K U2 C 5096-0 UA7915
R192 R292 A10266-6821 6.8K U100 U200 C 6911-9 UPA75
R193 R293 A10266-6821 6.8K U101 U201 C 4345-2 LM339
R194 R294 A10266-1041 100K U102 U202 C 4345-2 LM339
R195 R295 A10266-3021 3K U103 U203 C 6910-1 UPA76
R196 R296 A10266-4721 4.7K U104 U204 C 7558-7 MC33079P
R197 R297 A10266-1031 10K
R198 R298 A10266-4721 4.7K Misc.
R199 R299 A10266-1031 10K Board D 8369-7
R300 R400 A10266-1041 100K Socket C 3450-1 14 Pin (Qty 6)
R301 R401 A10266-1041 100K Nut A10102-5 Hex 6-32 (Qty 2)
R906 R1006 OPEN Heatsink C 5341-0 TO-220 (Qty 2)
R907 R1007 OPEN Tq Spreader C 6541-4 (Qty 2)
R908 R1008 OPEN Washer A10096-5 #6, Split (Qty 2)
R909 R1009 A10266-4741 470K Screw A10240-0608 Stainless (Qty 2)
R910 R1010 A10266-4741 470K J1 C 7593-4 5 Pin Header
R911 R1011 A10266-1521 1.5K J2 C 4508-5 16 Pin Socket
R912 R1012 A10266-4711 470 J11 C 7526-4 3 Pin Header
R913 R1013 A10266-1051 1M J100 J200 OPEN
R914 R1014 A10266-1051 1M J500 J800 D 6619-7 10 Inch Ribbon
R915 R1015 A10266-2201 22 J600 J700 D 6620-5 6 Inch Ribbon
R916 R1016 A10266-2201 22 Cable Tie C 1811-6 (Qty 4)
R917 R1017 A10265-10021 10K 1% TP 1 C 9450-5 Header, 6 pin RT Ang
R918 R1018 A10265-10021 10K 1% Spacer C 9225-1 Plastic Spcr (Qty 5)
R919 R1019 A10265-10021 10K 1%
R920 R1020 A10265-10021 10K 1%
R921 R1021 C 9079-2 200 Pot (CMR Null)
R922 R1022 A10265-66501 665 1%
R923 R1023 A10265-35711 3.57K 1%
R924 R1024 A10265-66501 665 1%
R925 R1025 A10265-10031 100K 1%
R926 R1026 A10265-66501 665 1%
R927 R1027 A10265-10031 100K 1%
R928 R1028 A10265-35711 3.57K 1%
R929 R1029 A10266-1041 100K
R930 R1030 A10266-1041 100K

40