Complete manual with clear schematic diagrams and printed circuit board layouts of two variants of the headset and the transmitter an old and a new version.
Also shows how the headset and the transmitter is opened and how transmitter and receivers can be adjusted and where to measure.
I had no problems to repair the headset using this service manual.
This is a great site. I placed my order and by the next am it was available for download. Had some problems with some missing copy on some pages. Once I brought the error to the OMC's attention, the issue was resolved. I'll come back again.
Mi spiace per non poter scrivere in inglese... ma sono veramente soddisfatto del servizio offerto. Grazie..!!
Text excerpt from page 16 (click to view)
6. Voice cannot be transmitted to other party (outgoing call).
Can the base and handset be connected? OK The 1 kHz, 3.3mV sine wavefor m i s a p p l i e d t o MC601 + side, can the 1 kHz sine waveform from collector of Q606 be fed? OK Check whether there is the 1 kHz sine waveform at pin 12 of IC602. OK Check whether there is the 1 kHz sine waveform at pin 22 of IC2. OK Check whether there is the 1 kHz sine waveform at the Q6 collector. OK Check whether the 1 kHz sine wavefor m from TEL-line output is fed. OK Check MC601 of handset. NG Check T1, RL1 and their pripheral circuits. NG Check IC2, Q6 and the pripheral circuit. NG Check IC2 and the peripheral circuit. NG Check IC602 and the peripheral circuit. NG Check Q606 and its peripheral circuit. NG See 3. The base and handset cannot be connected.