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any one can help on the amplifier circuit? (images)

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New Member
i am so sorry.....i forgot to draw the audio input jack.....
this is an audio amp.


1234.JPG i connected likethis
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Yes, both are wrong.

Your picture is very unreadable.
As far I can see it is powered by a DC source.

Draw it again without the connections and name the terminals so that I can help you.


Well-Known Member
Most Helpful Member
If the variabler resistor is supposed to be a volume control then it should adjust the level of the input, not the power supply DC voltage.


I think you did not get what I have said to you, kuang.

I'll name the terminals.

Switch -> Has 3 terminals. A, B, C. From Left to Right.
Potentiometer-> A,B,C. From Left to Right.

DC + jack -> Fuse -> Switch B.
Switch A -> DC + Input.

DC - jack -> DC - Input.

Audio + Jack -> Potentiometer A terminal.
Audio - Jack -> Potentiometer C terminal and Audio - input.

Potentiometer B -> Audio + input.

Led: You'll have to add a 1.2k resistor:
Switch A --- 1.2k resistor ---- Anode
Cathode--- DC -

Look at the led base. Cathode is the flat spot.
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