Hello,
I have a problem,
I found circuit in this forum:
www.e-ideja.com/dielkius/schematic.gif
And I made PCB for that:
www.e-ideja.com/dielkius/pcb.jpg
www.e-ideja.com/dielkius/pcb2.jpg
And there is a part schematic:
www.e-ideja.com/dielkius/parts.jpg
I have 2 transformers, one 33-0-33 and one 15-0-15 (there is values after diode bridges). I connected +33 G -33 then I conected +15 -15 and that transformer ground connected with PCB ground.
And a problem: When I turn it on nothing happens, LM's get warm, but speaker silent, no buzzz or etc. Whats wrong? Maybe you can help me..
I have a problem,
I found circuit in this forum:
www.e-ideja.com/dielkius/schematic.gif
And I made PCB for that:
www.e-ideja.com/dielkius/pcb.jpg
www.e-ideja.com/dielkius/pcb2.jpg
And there is a part schematic:
www.e-ideja.com/dielkius/parts.jpg
I have 2 transformers, one 33-0-33 and one 15-0-15 (there is values after diode bridges). I connected +33 G -33 then I conected +15 -15 and that transformer ground connected with PCB ground.
And a problem: When I turn it on nothing happens, LM's get warm, but speaker silent, no buzzz or etc. Whats wrong? Maybe you can help me..
probably impossible to tell you what went wrong.
It needs some troubleshooting with scope, signal generator and so on
at least there is one design error on the schematic...
a bias resistor at U4 is missing, you could try 47k from pin 3 to ground.
without a path for the bias current the operational amplifier could latch up. Maybe thats just your problem.
It needs some troubleshooting with scope, signal generator and so on
at least there is one design error on the schematic...
a bias resistor at U4 is missing, you could try 47k from pin 3 to ground.
without a path for the bias current the operational amplifier could latch up. Maybe thats just your problem.
btw. are the inputs of U5/U6 shorted?
Regards
Juergen
why a second transformer?I have 2 transformers, one 33-0-33 and one 15-0-15 (there is values after diode bridges). I connected +33 G -33 then I conected +15 -15 and that transformer ground connected with PCB ground.
Regards
Juergen
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