[Drake] PS-7 Problem

[AB3L1 at aol.com]

Let's try that again.
 
 
 
 
A few years ago I had a problem with my PS-7 and it sounds the same. Bear  
with me as it has been a while. There is a protection circuit that will drive  
the output to ground. At least that is what mine did. I seem to remember a 
heavy  amperage triac maybe?? When this thing clamped to ground it took out two of 
the  2N5301 power transistors.
 
Mine was a very early model and the later units might have had it removed.  I 
couldn't figure the reasoning behind it except to protect the TR-7 of course. 
 But then there is that fuse there also. A lot cheaper than the  transistors!
 
Hope it is leading you in the right direction Kevin. 
 
Bob  AB3L