I am now the proud owner of 2 DCC 900s. The first sort of worked for while. I did many reworks to fix cap damage but it stopped working. So I did the logical thing an bought another!
I have many hours into #2 but as of this eve all four corners appear to work - Digital Play, Digital Rec, Analog Play and Analog Rec (to DCC). So much damage from leaky caps on both SM boards, hope it keeps going. I’ll go back to #1 soon.
In the process of trying to understand the circuit and fix the RW board I moved the Analog Feedback twiddly pots. I didn’t touch the Bias ones. So my question is, has anyone got a procedure to calibrate the RW PCB? Nothing in the Service Manual except replace the whole transport in case of issues.
What I did was (a) photograph the positions first but then had a better? idea (b) - I used an analog Dolby level tape and set the feedback pots to provide the correct Dolby level at the motherboard test points. Of course this presumes the motherboard was perfectly calibrated to start with, something I could not confirm for sure.
Any better ideas/approaches?