Calling All Digibeta Experts DVW-A500

[ARC Tech-109]

I recently scored a Sony A500 Digibeta deck with numerous issues. First was in the power supply with a number of blown caps, spent an afternoon replacing them. Voltages are close to the board markings, the +8v is running at +7.60v while the -8v is -7.34v. both 15v rails are on target as is the 18v, 5v and 3.3v.

The one odd issue is a chroma green during analog playback, on the vectorscope I'm seeing good burst but no phase differences just a full saturation green, digital playback works just fine so I suspect its within the analog CTDM side... just where the heck is that?

Third issue is the tape elevator keeps cycling like a tape has been inserted going about 1/4 thru the travel then out again, I can insert a tape if I coax it in an follow the cycle.

Digital recording to a D32 tape via SDI works perfectly as is the playback, Im using a Newtek TC550 Tricaster for the SDI I/O and AES audio. I also cleaned up and replaced the old factory grease so everything is moving smoothly.
What I'm not finding is a service manual, there's an operations manual and parts breakdown pdf which I downloaded but it covers nothing I'm dealing with, given the sheer complexity of the A500 I suspect the service manual is going to be far larger than the NYC phone directory.

Anyone shed some light on this overly complex heavyweight beast? I know my way around the BVU decks but this has me stumped. Any help would be greatly appreciated.


109