Panasonic VP-7725D Audio Analyzer distorted oscillator

[Ray Gianelli]

My distortion analyzer has started to output distorted waveforms at the oscillator output.  While it at first appeared that this unit has two totally independent channels, it looks like they share a common oscillator.

Compounding troubleshooting issues is the fact that the construction of the unit makes it virtually impossible to do any power on testing.  The oscillator/attenuator assembly is on a plug in board beneath 2 other plug in boards.

Attached is a pic of the distorted output.

Here's a link to the service manual, which is impossible to find.  Thankfully I got a copy when I purchased it:
https://drive.google.com/file/d/0BxLVd1MVhl--ZTBMazRZd3RhWDg/view?usp=sharing

Any help with this would be greatly appreciated!

[schmitt trigger]

Are the board connectors a standard type?
If so, you will require to build extension patch cables, which will allow you to have all the boards spread out on the work bench.

[Ray Gianelli]

I've looked into that.  They're available from most online vendors.  The sockets on the backplane are Omron XC5B-6421, 6422 on the board, 2 of each required.  Fortunately I just need the one board on the bench.

[USMC_Spike]

I was looking for the pop corn guy to watch as you go along. 
Yes, there it is with a drink also.   

It's hard to get most of the Matsushita manuals for their gear.
Heck I never found a service manual for the VP-7635p so there is
sits. The -p is for Panasonic, -A for National, and I think -m was for
Matsushita.  I can find a $100 parts unit but shipping is 250.

I did find this manual number, don't know if it's correct,
VP-7635A nat-qvp7635a.

I put it here so I could find the number again.

I think I only need the four latching input signal switches for
the meter to work, of course I don't have them.

Good luck and hope your repair goes well.

Spike