Setting playback amplification on Beocord 9000

[marcham]

Hey, all. I’ve been working on a Beocord 9000, and everything has been going well (compared to a nightmare I’m having with a Beogram 8002).

I’ve already replaced the belts, swapped out the pinch roller, calibrated the speed, set the azimuth, and tested all functions. And a miracle: there are no dead display LEDs. Following the service manual, I set the playback level for 580 mV using a Dolby level, 200 pWb calibration tape.

Now, here are my two questions:

1. I had to fiddle with the board’s PB amplification controls (R248/R148) to get a signal due to oxidation — I ended up using Deoxit. I now want to set them correctly, but I am unsure how to do it, as the service manual doesn’t mention these pots. What are the test points and proper voltages? I already own a standard 315Hz 0Db calibration tape.
2. For adjusting the PPM, it notes having 600 mV through 2TP2; how does one achieve this? Am I using a signal generator and injecting a 600-mV signal into 2TP2 (if so, what frequency), or am I playing a particular tape?

Thanks for the advice, all!

• This topic was modified 13 hours, 18 minutes ago by marcham.

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