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.
The quality of this manual is good. It has all schematics and setup information for both the MDS-B3 and the MDS-B4. The scan quality is quite good, all pages are readable, This service manual also contains scans of the operating instructions from the User manual.
Text excerpt from page 26 (click to view)
Pin No. 37 38 39 40 41 42
Pin Name HFL SLOF CV-
I/O O
Description The HFL (high frequency level) signal is used to judge whether the main beam is positioned on the pit or on the mirror.
I I
Sled servo off control input. CLV error signal input from the DSP. RF output. Sets the RF gain and the EFM singal's 3T compensation constant togther with the
CV+ RFSM RFSO O RFSM pin. The SLC (slice level control) signal is output to control the DSP's data slice level of the
O RF waveform. I O I O I I I I O I +search with respect to the reference voltage). (Not connected) O O I VCC of servo and digital circuits. For the connection of bypass capacitor for the reference voltage. Reference voltage output. Sets the time constant for disc defect detection. For the connection of a capacitor to hold the RF signal peak. For the connection of a capacitor to hold the RF signal bottom. APC circuit output. APC circuit input. VCC of RF signal circuits. Input to control the DSP's data slice level. Ground of digital signals. Output for the focus search smoothing capacitor. The TBC (tracking balance control) signal sets the EF balance variation range. Not connected. Disc defect detection output. Reference clock input. 4.23 MHz is input from the DSP. Microprocessor command clock input. Microprocessor command data input. Microprocessor chip enable input. DRF (detect RF) is an output to detect the RF level. The FSS (focus search select) signal switches the focus search modes (+/-search /
