Various Defect Tips

TVs IN GENERAL Defect: Perfect image and low or completely absent sound, but with
loud, constant or slight noise on channels without broadcasts, or when changing channels. Solution:
Sound FI coil. I suggest removing the coil, breaking the internal capacitor, replacing it, and soldering it back.
place of the capacitor, under the board, a 100pf capacitor, then regulate the coil,
increasing to maximum volume and obtaining the highest volume at the adjustment. Another case:
Audio frequency filter.

Television with a completely green, blue, or red screen, with return lines.
in some cases the device turns off afterwards. Solution: Generally, the defect consists of
accumulation of dust containing carbon monoxide, on the legs of the transistors, on the board
RGB. Being conductive, it causes a short circuit in the transistors' collector. Just clean them. Others
cases: Shorted tube, or lack of voltage emission at the base of one or more transistors of
RGB, chroma CI.

COLORFUL TVs IN GENERAL Defect: Turns on the device and then the image of a
the broadcaster appears perfect and deviates from the tune that follows, in some cases the defect occurs in
only one or a few channels. Solution: PIP and AFT coil(s), or just coil of
video, depending on the device, with altered internal capacitor. Some remove the(s)
coils and apply nail polish, but I advise breaking the capacitor(s) and replacing them.
the coil(s), soldering the capacitor under the board. Calibrate the coils and tune them.
automatic, if it does not memorize any channel it is because the coils are uncalibrated.
Be patient and calibrate it/them patiently. Generally, with two identical coils, the
Capacitors will be 68pf. This way, the risk of the defect recurring will be practically null.
Bizu: To know the value of the capacitor to be replaced, just carefully remove the capacitor.
measured it in the capacity, so there will be no doubts regarding their value.
for the coil(s) are critical and require precise calibration.

TV CCE HPS1450
Not working.

HPS1425
Did not tune to any channel.

Cineral TV TC2011 or TC1411

170V enters pin 3 of the STR50103 but nothing comes out on pin 4
Defect: Horizontal output transistor shorted 2SD1878
Important: When changing the transistor, also replace C414 and C409 to prevent the transistor
burn it again. Note: Sometimes the TV returns to the workshop in a few days with the fly-back.
in short.

TV GRADIENTE GT 1420/ 2020/1422/ 2022

The standby light turns on, receives the command to turn on from the keyboard but the LED
The standby mode turns off, but there is no high voltage. I measured the voltage that enters the integrated circuit.
IC804 was entering 14, but nothing was coming out of it. Solution: I replaced IC 804 - 7812.
TV FIRST LINE DCT 1470M
Defect: Burnt fuse
Solution: Replace D816 and D817 (These diodes are not from the main bridge but from the power supply)
stand-by)
Place 1N4007

Mitsubishi TC1631
Does not memorize channels (Lack of -30v source on pin 2 of memory IC702)
R772 open

Mitsubishi 2098 or 1498

Case 1
There are 7 volts on pin 36 of the TDA8360 and horizontal pulses on pin 37, but there is no high signal.
tension.
Defect: Cold solder on pin 1 of the fly-back (re-solder all pins)
Case 2
There is voltage across the primary capacitor but there is no voltage on the secondary of the chopper.
R 904 open (solder all the pins of the chopper and fly-back)
Mitsubishi Model TC-21FS/2121FS DEFECT: alters the horizontal frequency and causes
Burn the R 555 that goes to pin (7) of the T.S.H (Fly-Back) and when connecting it already
Note the buzzing and the resistor smoking or opening immediately. SOLUTION: Replace C457.
and 458 of 100x35 and 470x35 that will be connected to the IC 451 (OUTPUT OF THE VERTICAL), which
disabled and because they are in the Vertical group, the Technician will never suspect the defect in the
horizontal, I replaced them with a new one, the device returned to oscillate normally.
Oh and don't forget to replace the resistor R 555 of 120R(Ohms) as well.

traces on the upper part of the CRT (Tube)

defect in the vertical; replace C459 - 100uFX35V Defect: vertical closed: replace R459
82Kohm.

Panasonic TVC TC-20C21/C7 chassis MX3-R

Solution: Q1135 (synchronization for the micro)

PHILCO PCS2952
It takes time to 'catch' when you turn it on. After warming up, it works but at reduced height.
Replace the capacitor: C 720

PHILCO HITACHI CPH-2 (All that use the 2SC 3678 in the power supply)
Philco CPH2 TV
operation starts to > hit/cross the horizontal > Solution: Replace the drive transformer
horizontal.

Defect: Ugly image, left side of the screen dark and the rest very bright.
capacitor C716 (4u7 x 250v). This capacitor is the filter of the power supply that feeds the collectors.
two RGB transistors.
Makes noise when turning on and soon stops
Solution: Measure the 115 source when turning it on, if the multimeter needle goes above 120V then the
the problem is in the source
Change C911.
However, if the pointer does not reach 100V, then you must replace the fly-back.

Defect: Failure to turn on, sometimes it turns on, sometimes it doesn't

Solution: Replace the switching transistor of the power supply

Works, but has an annoying squeak:

Solution: Replace C911

Defect: Does not work and makes a loud beeping sound

Solution: Replace the 4.7k X 3W resistor that powers the driver. Sometimes the 6.8k resistor.
what powers the oscillator
If you are getting too much noise from this source, replace the 3 small electrolytic capacitors.
from the same one and if it doesn't resolve, change the big one too (C912). I've already gotten it out of stock several times.
times. (there's a strong chirp)

Philco TV - chassis CPH-04 The television has a horizontal frequency issue and the image displays
Colors that tend toward green or purple. Solution: change crystal 503.

Philco CPH-5 TV
Mod. PCM 2046
Sometimes the 95V source runs out, sometimes the LED blinks, sometimes it does nothing. 150V enters pin 3 of
STR50103 and nothing happens. Solution: Solder the capacitor C 911 (220uF x 160V capacitor)

Philips CTO line TV

Case 1 - There is 300V at the collector of the BUW84 but only 115V comes out. (There is no short in the horizontal)
Replace all the metal film resistors (those large reddish 15k and 18K ones)
Case 2 - There is 300V on all pins of the BUW84
BUW84 short circuit defect. (re-solder all the pins of the transformers)
vertical intermittent

Philips TV - CTO Line Defect: tuning problem. Could not achieve a tuning.
perfect, there was overlapping interference on the image and when changing channels, it seemed that the
fugue tuning. Solution: replace coils S157 and S158 Defect:
Brightness Problem. The television without an antenna, the screen was dark. I even changed
several components, including the luminance IC but I did not resolve the defect; talking with
another technical friend, he gave me the tip. The solution was to replace the electrolytic capacitor
C221 of 150uF > you can put one of 220uF. When this capacitor is without
capacitance, even placing the antenna will not display any brightness on the screen.

Philips TV (with TDA8305)

Defect 1: Makes a noise in the sound as if it were a machine gun, the image becomes narrow.
and banging on the sides seeming like a problem with the power supply.
Solution: Replace the 22k ceramic capacitor (C162) that goes on pin 1 of the integrated circuit.
TDA 8305 (this defect is difficult to resolve because pin 1 is CAG, which makes it so that the
technical never think about this capacitor)

Defect 2: Width at maximum, no adjustment available

Solution: Replace the transistor TS517. Also check the small one that is connected to the base.
If you can't find the original, you can place the TIP32C inverted, that is, facing the heatsink.
Don't forget to put a mica to isolate.
I have a 29-inch Philips TV (29GX1895), which has two problems: 1st.
the volume of the TV reaches the maximum, only hitting half of the maximum; 2nd. The TV does not turn on
tuning mode - To enter this mode, you must press a button on the part
superior of the TV, but when we press it, nothing happens. If any of the colleagues has already
encountered this problem, and if you can help me, I will be very grateful.
The TV is in 'hotel' mode. You can resolve it by doing the following: 1- Using the remote control,
put the TV on channel 22; 2- Press simultaneously, on the top panel of the TV, the keys
volume '-' and channel '+'

Samsung TV - CN 5048V
Background image with overlapping traces. The TV displayed an undefined image.
And with traces, it was possible to identify that it had colors. I tested several.
components around the IC201, but I did not find any defective one. All that remains to me is only
replace the IC 201 to solve the problem.

TV SEMP - 20A82EAV
Defect - After replacing the fly-back, the brightness keeps fluctuating. Solution: Replace components
connected to pin ABL of the fly-back.

TV SEMP -TS207
Image with distortion at the top.
vertical

TV SEMP - TV2797
The vertical was closed at the customer's house. Upon arriving at the workshop, the TV worked.
It normally closed again after a few minutes. Solution: I soldered the output integrated circuit.
vertical that had almost invisible bad contact.

SHARP TV 14 T 51 does not work, three colored dots appear on the screen.
SWAP C616

TV Sharp 2025A (Valid for all models that use the 2SC 2365 in the power supply and fly-
back with built-in tripler
Defect: It has high voltage and the filament lights up but has no brightness; Sometimes the brightness
It appears and sometimes disappears. Solution: Replace the inductor L605 which is connected to pin 4 of the fly.
back.

Fault: 300V enters the collector of the 2SC2365 but nothing comes out of the emitter. There is no short circuit.
horizontal. Solution: Redo the soldering of the horizontal driver transformer. (Check others
bad contact points

Sharp C1453/2053 TV
Defect tips: Does not work, protection I shuts down. Solution: replace C666, which is located at:
TV SHARP - C 1453/2053 - Defeito: Excesso de altura: R911. Defeito: TV não funciona:
short circuit
Vertical stripes: R 512. Defect: Low protection shutdown - D611 with leakage (presents
zumbido) Defeito: Não funciona: IC 501 em curto. Defeito: TV não funciona: VARICAP.*
It's not just the Sharp TV, but all of them that come with a remote control. The varicap uses the voltage of
5V, which is the same supply voltage as the processor. If the varicap is killing this
voltage the TV will not turn on. Usually, it is the PLL IC that shows a defect, causing the
drop of 5V voltage.

TV SHARP (C/ IX0731)

Noise from the power supply, like 'bruuuuuuuuuumm'
Solution: Replace C712 (220 x 25V)
Note. Also replace C711 if it looks bad, for the purpose of preventive maintenance.

TV SHARP -TVC 2090H Defect: sound volume cut. When trying to increase the
volume, the same decreases as the vol + button is pressed, this happened both
to increase, as to decrease; more or less in the middle he would cut. solution: regulate
the coil T 301

Sharp TVC2199B
Defect: No high voltage. Measuring the power supply (pin 7) of the integrated circuit IC203 I found
only 7V where there should be 12V. This power comes from the transistor Q702 where it should enter
15V comes in through the collector and exits through the emitter. Since all the chopper's sources were normal.
so it couldn't be a problem with the primary of the power supply. I then replaced capacitor C731 and
the TV started working. Perhaps this defect also occurs in models that use the
IX0731 at the source

Sony KV2158 TV - 21' Line - Flat screen Defect: loses tuning, resulting in only static.
Solution: remove varicap, opening it solves all the terminals that are connected to the board
Principal.

Sony TV kv 2170S Defect: no SOUND Report: I initially checked the speaker

the speaker and the amplifier's power supply were both correct. This TV has mute
commanded on pins 2 and 4 of IC251, I checked that the voltage on these two pins was
high, meaning that there was the defect there. Short-circuiting the base and emitter of the transistor
The sound is back to functioning. Since the polarization of this transistor comes from pin 46 of
microprocessor, I measured the voltage and found it close to 0V. Disconnecting this pin, the MUTE
It stopped working and the sound started working again. This pin (46) is leaking to ground;
Caused by the tension of +16V, coming from the sound polarization; while the
the microprocessor operates with only +5V. If you want to replace this integrated circuit, you must
make the following changes: 1) Remove resistors R268 and R470 and at their ends
place a 13V 1/2 W zener (the anode of the zener should be connected to the R040 and its
cathode connected to R265/266. 2) Place a 100k resistor from the anode of the zener to the
mass. 3) Replace the resistor R266 of 33k with a 10k resistor.

Imported TVs (Popularly known as made in Paraguay)

Tips for defects in imported TVs. Brands Talent, Kirey, Baysonic and ... The chassis of these
The TVs are identical. The defect is in the power supply, the voltage of the power supply increases.
for more than 180V, reaching even up to 250V causing an abnormal high voltage and
download, at the tube's anode. Solution: replace the 47uF x 25V electrolytic capacitor.

SOUND, RADIO
Marca
Aiko FM digital tuner without tuning oscillator trimmer
Aiko 3in1 AHS 107 Canal right mute CI500 (STK441), C512 and C513
Bosch Car Radio DH25 Low volume right channel C2560 (0.22 µF)
CCE 3em1 SS-5880 With sound IC901 (TA7417AP) and Q902 (BC547)
Century Sat receiver USR1900 inoperable D124, CI-U112, R126 and tuner
Delta Amplifier DBR-904 Inoperable R14 (4.7 R 1/4 W)
Frasat Sat receiver SRE500A Inoperable TF-1 (transformer)
Amplifier Gradient M120 Inoperative Rectifier bridge and C134 (5000 µF 35 V)
M246 Amplifier Gradient Inoperable, blown fuse Output transistors and exciters
rights and CI901
Pro 2000 MKIV Amplifier Gradient Open fuse TR4, TR5, TR8, TR9, TR10 and
TR11 in short
Gradiente CD Player CDP/AT3 does not play the CD CI TDA7073A and optical reader.
Gradiente CD Player 5 CD Poor playback Adjustment of the trimpot next to the laser
Gradient Receiver S-96 Inoperative, fuse D106 and D107 open (SKE 3/20)
Gradiente Receiver STR 1050 Distortion in the left channel T108 and T109
Gradient Receiver 1360 FM without sound CI1 (CA3189)
T1 Tuner Gradient Signal LEDs on IC601 (CA3046) lit
Gradiente Tape-deck CD3500 Inoperative D615, R624 (33 R) and X605 (BD135)
Gradiente 3em1 MS-300 FM inoperative CI701 (LA1186N)
Grexnolds Receiver LR 1000 FM stereo not working CI1 (CA1310)
Kenwood Receiver KT-2001A FM with low volume Q6(2SC381)
Motorola Mobile Radio GM300 Low Transmission Power Q2330
National AM-FM RF4210W Inoperative C18 (4.7 µF 25 V)
Philco Radio B-482 FM with low volume T101 (A040), T102 (A041), T103 (A041) and T104
A041
Philco Receiver B-481-3 without AM and FM tuning R212 (1 K)
Philco Receiver PSR-30 FM inoperative T101 (transistor B153)
Philco Hitachi 3em1 PCS32 Inoperative, with noises C206 (0.22 µF)
Philips Tape-deck AW-620 Lights off D363 (zener 8.2 V 400 mW)
Philips Tape-deck AW-620 Play does not operate TS461 (BC328)
Philips Tape-deck 06AC060 Inoperative on channel TS432A, TS432B, C760 and R606
Polyvox Radio-grav RG-700 AM and FM inoperative CI1
Polyvox Receiver PR1500S AM and FM not working T901 (transistor)
Polyvox Receiver PR1800S AM does not work Q701 (PE255D)
Polyvox 3em1 PS-900 Left channel of the tape without sound R847 (470 K)
Revox Tape Recorder B77 Insufficient Rotation C729 (10 µF 16 V)
Sansui Amplifier AU517 left channel inoperative R700 (100 R)
Sanyo Radio RP-5040 unstable tuning in AM Q103 (2SC930E)
Sony Receiver STR-11BS Weak FM signal TR01 (2SK61 - FET)
Sony 3em1 HMK353-B5 Inoperative C913 and C914
Spectro Amplif SQA 2100 left channel with low volume C123 (47 µF 16 V)
Tec Sat Receiver T-3200 Intermittent operation Bad contact in D5
Unimack Receiver UR390 FM with noise R20 (4.7 K trimpot)
Unimack Receiver UR390 Noise on a channel when turning off C3 (47 µF 25 V)
Yang Receiver YR7400 stereo LED off Pins 4 and 8 of CA3089 with poor contact
Yang Receiver YTR-380 Inoperative AC fuse, transistors TIP41C, 12 V zener from the power supply.
IC3089

Printer LX 300, FAULT: When sending to print on win95 or win98, it would turn off the
printer SOLUTION: disconnect pins 14 and 36 from the communication board
CENTRONICS Or if you have an updated EPROM, just replace it.

I tried to do it like in the example above and it didn't work. Instead of cutting or releasing the pins.
14 and 36 of the small plate, I cut the wires of pins 14 and 36 of the centronic parallel cable.
printer and it worked.

EPSON LX-300 Printer Defect: Prints with various flaws in the printing (lines).
Solution: Check if there is any Tr. C-5060 from the Plate that is open at the collector. If so,
replace with Tr. TIP 41C ... Note: Check the print head if there is no coil
with the variation of OHMs.

HP820 Cxi Printer Issue: It starts printing well, then after a while
there is a communication error and it stops, the lights keep flashing. Solution: after a lot
breaking my head, trying to solve in the electronic circuits, I found the engine of
transport of the head releasing iron filings, I just replaced it and everything was resolved.
I hope this helps you.

HP 820 Cxi PRINTER FAULT: Printer prints part of the page and freezes,
indicating that it is out of paper. SOLUTION: Replace electrolytic capacitors C3 ( 330/35V )
the C5 (560/35V) of the print head board. Note: Capacitors usually
They present normal readings on the capacitometer, but vary capacitance in operation. The C5 can be
replaced by 680/35V.

I fixed one with a similar defect that would print a test page and right after that
Pulling the paper stopped and the LEDs blinked. Solution: dirty optical tape or position sensor.
dirty car. Disassemble the car to clean the sensor because with it dirty the CPU doesn't know where the car is.
this is to prevent blows to the sides.

CDs IN GENERAL
I would like to leave this tip that has helped me many times. I don't know if you already know it and
agree but.... It concerns the defect of CD equipment that uses the optical unit.
CDM12-1 (Gradient, Philips, CCE). It is the unit that when bought new comes
with the two motors... and has a very thin flat cable (made of plastic material)... In 90% of the
cases I encountered where the equipment does not read the CDs, sometimes indicating "no disc" or
the error is due to the internal dirt that remains in the duct between the mirrors and the leisure...
solving this problem often requires more than just cleaning the outer lens; it's necessary to wash the
unit!!! To do this, do the following: 1- remove the mechanism with the unit of the equipment( to
sometimes it can be removed without much disassembly); 2- remove the part that contains the unit
dismantling the mechanism, 3- put a little liquid detergent inside a cup
with water and immerse the unit inside; wait about 10 minutes and then dry with a cloth
soft; a hair dryer and a blower; 4- Reassemble carefully and do the test. I had many
positive results and I hope you have them too.

Hey guys, so I got a Philips CDP that uses the optical unit CDM 12.1 and it doesn't
it did not turn the spindle motor at all. It seemed to me that the defect was on the board but
only changing the unit while keeping the original engines of the pickup set
same started working again. NOTE: We should always keep the engines of the set switching.
only the unit.

CD player model CDP-AT3 brand Gradiente

Coils of the unit vibrating and error message on the display.
(TDA7073) with defect; it is the motor driver.

Fax Machines
Fax Siemens HF1710
Secondary sources inoperative (there is 350 V on the primary)
Replace the capacitor C10 of 15uF (you can use 22uF x 63V)
MICROWAVE
Re: Samsung microwave 5925: it wasn't accepting the start function, I even suspected the
After hours of being turned off, I found that it accepted the function, so I decided to test the
components around you and found the diode 1n4148 near the flat cable with low leakage
problem solved.

Monitors
AJV 1428NI
Defect: I got the monitor with the screen completely dark. I then decided to increase the screen and
the image appeared with a very narrow frame. I measured the source at 150V across the capacitor
C812 was only at 80V. Examining capacitor C812 (100uf x 200V) the
it was also a bit loose at one of its terminals and there were signs of leakage.
Solution: I replaced C812.

COMPAQ PRESARIO MODEL 462 MONITOR DEFECT: INOPERATIVE (Led

frontal was not signaling) Checking the primary source, it was found that 152 volts were arriving until the
transformer (chopper), but without voltage on its secondary. The zener 904 was
swapped due to being short but the fault persisted. Tested Q908 and Q906 with minimal leakage
between the collector and the base, but due to doubt they were swapped, and fortunately the monitor
it worked.

FIVE STAR FT5015

Defect: Narrow image, does not adjust width
Transistor Q 413 with open junction
If the problem is not resolved, check components connected to its base.

IBM G50
Image shifted entirely to the right, horizontal position adjustment does not work
The image looks ugly and undefined, with many dark stripes.
Change the capacitors: C205, C225 and C351
A friend's doubt:
I have an IBM G50 monitor in my assistance that arrived with a lot of brightness and
retracement lines
I уменьшил экран на fly, но остался без контроля яркости, и когда он выключается, появляется.
quickly a strong bright bridge in the middle of the tube. I have already tested the brightness circuit but
I didn't find any problem.
Check R714 There needs to be a negative voltage there of about -40V If there isn't
this tension is the problem in this mesh.
replace R424
Defect: Lack of one of the primary colors.
the CI LM 1203N is the culprit! (the signal is 'in' and not 'out') With the oscilloscope we see the
Signal 'cute' entering CI 1203N, but it is not sent to the amplifier. It exists.
a series of "hanging" resistors right next to the LM1203 (all precision) If
if any of them changes, (more than 3k) the IC does not amplify the input signal.

Monitor Orchestra model: Bugle-14

Defective image ugly, when increasing contrast all the characters spill out, lacking blue.
Solution: Solder R233, rectangular white resistor of 1K2 x 5W. Although it seems that it is
The soldier is actually not making contact. If another color is missing, check the soldering of the 3.
power resistors. It is interesting to note that the absence of the resistor does not only cause
absence of a certain color but interferes with the image quality of others
cannons.

Model 328 UIS monitor

vertical folding when height or image position is increased Defect:
Power resistor feeding the altered TDA1675.
Defect: image with 'comet tails' at points of highest contrast Solution: At
most of the time it is the small electrolytics on the z-axis board [they are usually
dry ones], but sometimes they can be the 47 ohm resistors that are underneath the resistors.
of power, that are in series with the transistor colors.

Samsung SyncMaster 3
There are 150 V on the primary and nothing on the secondary, pin 7 of the 3882 with starting voltage.
Fault: ceramic capacitor of 1k/50v that goes on pin 3 (return) of C.I. 3882, when measuring on
The multimeter seemed good but shorted when energized.

CVM - 4967T
Defect: yellow screen when moving the socket shows blue.
RGB transistors (in this model, the transistors are not on the tube board but on the board)
from below under an aluminum shielding).
Defect: Pincushion distortion, replace C207 from 0.47uF to 1uF x 50V.

Terminals
Unisys EI-230 Terminal Defect: Does not accept interface configuration (interface in mode
converter) Cause: Burned 8530 integrated circuit of the interface board

Unisys EI-230 Terminal

Solution: the only way in this case is to reset the terminal configuration; to do this change the
JP4 strap on the logic board (it is near the E2PROM X28C16); connect the terminal and wait
It gives the message 'E2PROM read error'; enter the configuration and exit it with
Shift + F10, turn off and return the strap to the original position; after that, just turn it back on and the
the password will be the default password ("MENU")

Here are some more defects of the EI-230; the defects in its analog part also count.
for the monitor EI-100, since they use the same deflection board. Defect: Does not turn on,
It sometimes turns on; there is tension in capacitor C23 Cause: Transistor Q1 (2SD1992) with leakage.
Resetting
feeding the logic board, and this can have three different causes: - Poor contact in the cable
What powers the logic board: Measure the voltage at the extreme pins of the connector CN1 on the board
of the deflection and at the extreme pins of the power supply of the logic; if the difference between
if the tensions are greater than 0.1 volts the cable is loose (the easiest way to
improving the connection is soldering the connector pins). - Low source: Check during
more or less 1 minute if the output voltage of the source does not vary by itself; if it does not vary it is
just adjust the voltage on the trim-pot R4 to approximately 5.1 volts. - Unstable source: In this
the terminal keeps resetting when it's cold and takes a long time to start booting up;
replace capacitors C5, C7, and C11 (470 uF / 16 volts). Defect: No communication Explanation:
Hardly the cause of this defect is the 1488 and 1489 integrated circuits. If you have already replaced them and not
adiantou, check if the interface is being fed. The easiest way to see this is
measure the voltages at the main interface connector; place the black lead of the multimeter on
put the black probe on pin 7 and the red one on pin 2 (it should have at least -8 volts) and then place the red one on
pin 20 (must have at least +8 volts). In most cases of power failure in
the cause is a poor connection in the cable that powers the logic. If everything is fine with it,
check the voltages on the integrated circuits U1 (7812) and U2 (1912) on the deflection board obs. The EI-
230 does not wait for the CTS signal to transmit, it generates the CTS internally; the "Delay of
"CTS" in the interface configuration should never be lower than that of the modem; it is best to leave it.
the terminal delay is greater than the modem. Defect: Closed vertical Solution: Replace the
integrated U102 (TDA1170; can use TDA1175) and the resistor R115 (68 ohms / 2 watts)
Horizontal without linearity / not adjusted
changed; try to replace it with a good quality one because this capacitor heats up a lot.
Defect: Low contrast even with the internal and external contrast adjustment at maximum
Video driver (CR2424) without gain.
Integrated LM1201 with defect.
Capacitor C110 (22 uF / 40 volts) dry Defect: Insufficient height, even adjusting for
the maximum Cause: Capacitor C112 (1000 uF / 35 volts) altered. Also check if the
resistor R115 is not altered
ADD terminal model 8433
The display appears, but with no video signal Cause: 2816 on the burnt logic board (it does not
it has nothing to do with the video amplifier, but it prevents the logic from initializing
completely); this defect is rare, in most cases the 2816 simply stops
store the configuration
Terminal ADD model 8349
loop connector, but does not communicate with the server Cause: defective Z80 CTC; it generates
the clock and the timings for the interface
ADD terminal model 8433
When will you respond to the poll Cause: Z80 SIO-2 burned Equipment: ADD Terminal
(all models that use the PAT-05 deflection) Fault: burnt flyback / the original does not
It is found in commerce Solution: replace it with an Ipeco 114/150, which is the same as the original
(Feg4017)

QUESTIONS ABOUT VIDEO CASSETTES

VCR AIWABR77 - Malfunctioning flashing display. Solution: Electrolytics = 22ufx63v, 47ufx35v
the 47ufx16v dry (without capacitance)
JVC video cassettes - 671, 641, 651 DEFECT - chewing tape. Diagnosis - check if
Upon returning the tape with the image, the tape loosens and soon returns to normal. Solution - Gear in
intermediate pulley stuck. The lubrication dried up and turned into glue. Remove the arm from the pulley.
intermediary, disassemble by removing the lock and clean the metal shaft well (especially
under that type of plastic cup) and lubricate.

Tips for maintaining the JVC 641/651 VCR Power supply failure: the
The defect that this power supply presents is usually the leakage of electrolytic capacitors.
causing the fountain to stop; even replacing them the fountain does not oscillate. Solution: remove the
transform the board and then wash it with soap or detergent, with the help of
a brush or comb, after washing, dry it with a hairdryer. If the plate
if it is not too damaged, you will definitely get a positive result.

PANASONIC G21
Defect: When we push the tape in, the display turns off.
Solution: This defect occurs because the power supply does not support pulling the mechanism, in this case it should
the electrolytic capacitor of 10uF x 25V that is on a small board in the primary of the
source.
Defect: Mechanic goes crazy:
Solution: Replace the photo-transistor that is on the left side of the box.

Video nvfj605br panasonic Message: hello I got this video with a lot of noise in the sound
Note: this video is hi-fi stereo. I checked the source and found the 330uF/25 capacitor.
it is located at source and c105b

Panasonic NV-F70 Video Cassette

When the VCR is turned off with the tape in the slot, or when trying to use rewind or fast forward,
the video freezes the functions, not allowing any command, removing the tape manually, and
inserting again, it works normally until some of the above steps are taken. Solution. The
F70 uses the 'G' mechanics with one additional feature, it has a control key that goes in the
drive gear of the pullers, near the indicator key of the tape seal, clean and adjust
the contacts. Video cassettes that have the auto tracking feature, when it starts to drizzle and
in some cases losing sound or getting a blue screen, clean the audio and control head.
This is a very common defect in current videos.

L26
The video is with the display off, the power supply seems good, it has all the voltages and the
the video works all functions, including the tracking light blinking normally when playing.
Solution: I have encountered this defect 3 times and in all 3 instances the problem was with a trace.
broken underneath (or near) the Nickel-Cadmium battery...remove the battery and check this...

SEMP X470
Defect: The display keeps flashing and the power supply is oscillating.
Solution: Change one of the electrolytic capacitors located in the 6V power supply

Broksonic
Defect: Mechanic goes crazy
Solution: Remove and clean the position key

SHARP VC762
Defect: When pushing the ribbon in, it comes back. Sometimes it is almost loaded.
head
but it's a little bit lacking
Solution: Replace the small belt that goes on the loading motor.
Posted by Adrih at11:46:00