Regarding the Sony WM-EX 502 507 WM-FX503 507 509 I have several broken models of these now, when the belt is replaced the walkman no longer goes in to play / rew / ffwd modes, although there is power and the motor does turn. I having a difficulty understanding the service manual. Which instructs: 1. Input square wave to TP 2. Press FFWD or REW 3. Remove Audio Board 4. Input square wave to TP 5. Press Play 6. Remove Audio Board 6. Input square wave to TP 7. Press Play button twice 8. Remove Audio Board I have an audio oscillator but it doesn't go below 20Hz; the manual states that it requires 1Hz square (EX models) / 5Hz sine (FX models) What I don't understand in the steps above is what am I supposed to do after removing the audio board - run it without it interfacing with the S701 switch? Which the manual advises you not to do because you will have to start at the beginning.
