I think my dad had this amp but cant remember exactly. A picture would help.
Anyway, these use STK amplifier modules which can often die. The power supplies for the opamps are also generated by zener referenced transistor regulators. These transistors often run HOT and fail. Also the resistors feeding the zener on those regulators can fail. Check the voltages on pins 4 and 8 of any one of the opamps you'll find.
Anyway, these use STK amplifier modules which can often die. The power supplies for the opamps are also generated by zener referenced transistor regulators. These transistors often run HOT and fail. Also the resistors feeding the zener on those regulators can fail. Check the voltages on pins 4 and 8 of any one of the opamps you'll find.
Taken apart.
I found this on the net. Mine is taken apart.
It makes a pop out of both speakers when I flip the tone defeat switch.
I have swapped the stk modules from front to back but there was no change. This amp makes sound in 1 channel, and that didn't change with anything. It is I thought, losing it between the tone/volume board and the selector boards/switches.
Thanks for replying.
Cool.
Srinath.
I found this on the net. Mine is taken apart.
It makes a pop out of both speakers when I flip the tone defeat switch.
I have swapped the stk modules from front to back but there was no change. This amp makes sound in 1 channel, and that didn't change with anything. It is I thought, losing it between the tone/volume board and the selector boards/switches.
Thanks for replying.
Cool.
Srinath.
Attachments
obvioulsy there might be some cleaning issue with the switces and pot of such an old amp but the reason of this may lay on the electrolytic caps of the amplifier ...
any small ofset that exists in the preamp section or elsewhere can be caused by electrolytics failure somewhere inside the amp
keeep in mind that any failure in the small electrolytics in the amplifier can cause a number of problems that will eventually take the amp down.
remove any of them check for leak or value drift then expect most of the others to have the same problems
replacing all will probably cost next to a few usd ... replacing all is an oportunity to upgrade most of them to something a lot better ... that will also change the total performance of the amp beyond a simple repair ...
here is a can box with help http://www.diyaudio.com/forums/solid-state/136261-vintage-amplifier-repair-upgrade-manual.html
regards sakis
any small ofset that exists in the preamp section or elsewhere can be caused by electrolytics failure somewhere inside the amp
keeep in mind that any failure in the small electrolytics in the amplifier can cause a number of problems that will eventually take the amp down.
remove any of them check for leak or value drift then expect most of the others to have the same problems
replacing all will probably cost next to a few usd ... replacing all is an oportunity to upgrade most of them to something a lot better ... that will also change the total performance of the amp beyond a simple repair ...
here is a can box with help http://www.diyaudio.com/forums/solid-state/136261-vintage-amplifier-repair-upgrade-manual.html
regards sakis
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