CB RUDY "Rodrigues"
Test equipment required:
Power Supply: 13,8 V Frequency Counter Dummy Load 50 ohm Oscilloscope
DC Amperemeter RF SSG AF SSG
Preparation alignment:
Clarifier Mid.
SQ GAIN Max.
AF GAIN Max.
RF GAIN Max.
MIC GAIN Max.
MOD, S/RF S/RF
NB/ANL Off
Band D
Channel 19 (27.185MHz)
Reading Point Condition Adjustment Procedure
PLL
IC5 Pin 3 - Check 10.2400MHz
TP2 Band:D, Ch.:40 L17 5,0 Volt
TP3 - L18 Maximum on Oscilloscope
OSCILLATOR
13.560MHz X-tal
IC10 Pin 9 AM L19 16.0400MHz
IC10 Pin 9 USB L20 16.0425MHz
IC10 Pin 9 LSB L21 16.0375MHz
IC10 Pin 9 TX AM VR21 16.0400MHz (TX-Frequency)
14.010MHz X-tal
IC10 Pin 9 AM L19 16.4900MHz
IC10 Pin 9 USB L20 16.4925MHz
IC10 Pin 9 LSB L21 16.4875MHz
IC10 Pin 9 TX AM VR21 16.4900MHz (TX-Frequency)
14.460MHz X-tal
IC10 Pin 9 AM L19 16.9400MHz
IC10 Pin 9 USB L20 16.942525MHz
IC10 Pin 9 LSB L21 16.9375MHz
IC10 Pin 9 TX AM VR21 16.9400MHz (TX-Frequency)
All models:
TP5 TX AM L26 10.6950MHz
TP6 RX USB L27 10.6925MHz
TP6 RX LSBL28 10.6975MHz
TP5 TX USB VR7 SSB Modulator Balance
RECEIVER
RX AM L6 L7 L8 RF Input
RX AM L10 L11 L12 AM/FM/SSB IF
RX AM L3 L4 AM/FM IF
RX FM L5 Discriminator Coil (FM Demodulator)
TP1 RX USB L1 L2 Noise Blanker IF
RX USB VR3 SSB Squelch
RX AM VR4 AM/FM Squelch
AM/FM S- Meter RX AM VR1
SSB S- Meter RX SSB VR2
TRANSMITTER
TP9 (+) TP8 (-) Bias Driver VR11 10mA
TP9 (+) TP7 (-) Bias Finale VR10 100mA
TP9 (+) TP7 (-) Bias Finale VR20 100mA
TX AM L42 Maximum
TX AM L43 Mixer Coil (VCO-frequency input)
TX AM L44 Mixer Coil (TX-carrier 10.695MHz input)
TX AM L40 L42 Maximum RF output
TX AM L33 Minimum Harmonic
TX AM VR13 15 Watt (30 Watt with Dual Finale output) AM/FM
TX USB VR12 20 Watt (40 Watt with Dual Finale output) SSB (ALC)
TX AM VR14 90% AM-Modulation (AMC)
TX FM VR5 2 kHz FM-Deviation
TX CW VR16 CW Tone (Not in all model`s)
Power Meter TX AM VR8
Microphone Connection
Pin Description
1 Ground
2 Microphone
3 TX Key (Connect to Ground)
4 Speaker (Connect to Ground)
Dual Finale output modification
Frequency List for Alan 87
COMPONENTS
Alan 87 Schematic Diagram
Cherokee CBS-2100 Schematic Diagram
Galaxy DX73V Schematic Diagram
Galaxy DX88HL Schematic Diagram
Cobra 148GTL-DX Schematic Diagram
MC145106P PLL Frequency Synthesizer
S042P TX Mixer
KIA6410S Oscillator, Mixer and Amplifier
uPC1028H FM IF Amplifier and Detector
AN612 Balanced SSB Modulator
TA7222 Audio Power Amplifier
NJM4558 Dual Operational Amplifier
TA6324 Quad Operational Amplifier
2SC1969 RF Finale Transistor (SuperStar 3900)
2SC2312 RF Finale Transistor (Alan 87)
2SC2166 RF Driver Transistor
2SC2086 RF Pre-Driver Transistor
2SB754 LF Power Transistor
2SA473 LF Power Transistor
Improved receive gain
Quieting of AM reception and improving gain of incoming signals is a common request from radio
operators. In the first stages of the HF input 2SC1674 transistor can be found. This transistor is
responsible for the amplification of a small detected signals. A problems exist if the transistor itself is noisy
as is such the case of the 2SC1674 when compared to other low noise packages. Along with the
amplification of the incoming signals is transistor noise. Replacement of this transistor with a higher gain,
lower noise transistor greatly improves the signal to noise ratio of your receiver.
We will use an 2SC2999 transistor that has higher gain lower noise characteristic. Replace the 2SC1674
(TR17) with an 2SC2999 (or similar low noise and high gain transistor) to achieve this improved signal to
noise ratio.
Re-Adjust L6 and L7
The gain will improved with more than 6dB with the same signal to noise ratio.
CB RUDY "Rodrigues" PORTUGAL
