Sansui G-7700 Recap Issue

[phoney99]

Hello everyone,

I've started down the daunting path of recapping/restoring a late model G-7700 (The one with MT200 Sanken outputs).
The unit has shorted output transistors and drivers on one channel and most likely many other issues. I have started recapping and removing the corrosive glue and have already found multiple caps, resistors with serious corrosion damage.

Does anyone have an newer Schematic of F-2980 Power Amplifier board? My version is very different from the readily available early version (TO-3P Outputs).

1st issue I'm facing is Capacitor C626 in the Power Supply. I believe it should be a Bi-Polar 100uf/6.3v. however this unit has a Polarized 100uf/25v. Looks like it may have previously been replaced as all other caps are Elna and this is a Nippon Chemicon.

Any help will be greatly appreciated.

Peter

 

[kwayde]

Hello everyone,

I've started down the daunting path of recapping/restoring a late model G-7700 (The one with MT200 Sanken outputs).
The unit has shorted output transistors and drivers on one channel and most likely many other issues. I have started recapping and removing the corrosive glue and have already found multiple caps, resistors with serious corrosion damage.

Does anyone have an newer Schematic of F-2980 Power Amplifier board? My version is very different from the readily available early version (TO-3P Outputs).

1st issue I'm facing is Capacitor C626 in the Power Supply. I believe it should be a Bi-Polar 100uf/6.3v. however this unit has a Polarized 100uf/25v. Looks like it may have previously been replaced as all other caps are Elna and this is a Nippon Chemicon.

Any help will be greatly appreciated.

Peter

You should fix the problems before beginning to replace caps, etc.
You may end up adding more problems which will make finding the original problems that much harder.