Very good manual, in depth and complete. Only criticism is that some of the circuit diagrams are slightly blurry and hard to follow for long periods of time, but this is to be expected. Perfect for any maintenance required. Also contains the wiring diagrams of the control cable for constructing extensions.
Detailed SONY CFD980 Service Manual at an easy to find one stop shopping. Make my radio hobby technically interesting. Thanks.
Text excerpt from page 21 (click to view)
10. TROUBLESHOOTING
1. Intermittent display
START Y Is the Heat seal defective ? N Y Is the battery contact weak ? N Are there short circuit around the pins Y of the LSI (HC3009-01-F1) ? N Is the soldering weak ? Y N Replace the PCB ass'y Replace Clean and adjust pressure of contact Resolder Resolder
2. Erratic display
START Is the Heat seal defective ? N Is the LCD defective ? Y Y Replace Replace Check or replace the chip capacitors C4 ~ C8 Resolder
N N Are the voltage V0 ~ V4 OK ? Y Are there short circuit around the pins of the LSI (HC3009-01-F1) or between the 2 pins of Y the crystal oscillator (·1) ? N Are there short circuit around the pins of the RAM and ROM ? N Replace the PCB ass'y