I built Leak TL/50 Plus from scratch ,point to point. The only thing I changed
is the layout: Kt88, EF86, 12ax7 KT88 in that order. All voltages appears fine.
The amp is playing wonderful untill I connect the Feedback. Then it started motorboating at a rapid pace. OK I know for sure that is connected right. It's
Edor transformer and it was in another amp. I tried many resistor but it only
stop if I use like 1 or 2 megs.
OK, I am a dilettante and I am working with only a mulitimeter. Any help or
suggestions will be appreciated.http://44bx.com/leak/Leak/Circuits/tl50_ecc83.JPG
is the layout: Kt88, EF86, 12ax7 KT88 in that order. All voltages appears fine.
The amp is playing wonderful untill I connect the Feedback. Then it started motorboating at a rapid pace. OK I know for sure that is connected right. It's
Edor transformer and it was in another amp. I tried many resistor but it only
stop if I use like 1 or 2 megs.
OK, I am a dilettante and I am working with only a mulitimeter. Any help or
suggestions will be appreciated.http://44bx.com/leak/Leak/Circuits/tl50_ecc83.JPG
The primary of the output transformer could be wired wrong; that is,
the upper tube to the lower taps, and the lower tube to the upper taps.
No doubt the secondary is wired ok though.
the upper tube to the lower taps, and the lower tube to the upper taps.
No doubt the secondary is wired ok though.
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I just had this problem on a kt77 P-P amp.
I switched the polarity on the secondare and it was solved.
Try it.
I switched the polarity on the secondare and it was solved.
Try it.
The secondary has an 8 ohm tap and is not symmetrical. It would be symmetrical if there were
only 4 and 16 ohm taps. Here it is not appropriate to switch the 0 and 16 ohm secondary connections.
As an alternative to rewiring the output transformer primary, instead you could exchange the driver
connections to the grids of the output tubes.
only 4 and 16 ohm taps. Here it is not appropriate to switch the 0 and 16 ohm secondary connections.
As an alternative to rewiring the output transformer primary, instead you could exchange the driver
connections to the grids of the output tubes.
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Wow! I am so happy. I don't know if you guys understand how valuable your help is;how
much it is appreciated. Rayma, your are the champ! I did exactly as you stated and there
is no more motorboating. How sweet it is not to hear it.Thank you, thank you and thank
you a million times.
much it is appreciated. Rayma, your are the champ! I did exactly as you stated and there
is no more motorboating. How sweet it is not to hear it.Thank you, thank you and thank
you a million times.