does anyone have circuit diagrams for the counterpoint sa4.
thank you.
I have problem on 1 amp,it trips speaker relay out.any know what may be causing this.
thank you.
I have problem on 1 amp,it trips speaker relay out.any know what may be causing this.
😀😀
Bloody horrible IMHO! Recipe for a tube eater--Now we know where all the 6LF6's went!.....😱
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thanks for the sch,do u have it for the regulator board.i have one working super but other trips speaker protection relay out.
Prolly one o/p valve is stuffed,-As I said, Its a diabolical design IMO-A try see if still trips when you transfer output valves from one set to the other.
---A DC Coupled OTL--What kind of crack were they smoking!! Seems to use a Transistorised Servo--To keep it from self-destructing.....
---A DC Coupled OTL--What kind of crack were they smoking!! Seems to use a Transistorised Servo--To keep it from self-destructing.....
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6FS5 remote cutoff guided grid RF tubes for the front end????????????
No equalization of gain for the top and bottom output tube banks????????????
Uhh, is this some 3rd world country design or something???????? Scrap box challenge?????
I would say that a TOTAL RE-DESIGN is callled for, DO NOT repair.
No equalization of gain for the top and bottom output tube banks????????????
Uhh, is this some 3rd world country design or something???????? Scrap box challenge?????
I would say that a TOTAL RE-DESIGN is callled for, DO NOT repair.
Woops, I just noticed that it DOES have a bootstrapped splitter for gain equalization (V9 plate load). Looking a little better now. The 6FS5 for the V9 splitter is OK (low screen current and gm degenerated). But V10 has got to be non-linear.
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It was designed by none other than Roger Modjeski of Music Reference, his first OTL design, he has got much better ones now.
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well it may be a bad design but they sure do sound good,the working one I have sounds great,have tried swappimg tubes over and still trips speaker relay out.
Also try a number of 12AX7 tubes. In my experience a 12AX7 tube somewhat out of specification will result in the amp not balancing. A lot of trouble-shooting may be avoided this way (I speak from experience).
counterpoint sa4
amps fixed,lots of faulty caps on driver board and a couple of blown zener diodes.both sound superb now.
amps fixed,lots of faulty caps on driver board and a couple of blown zener diodes.both sound superb now.
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