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This is the 555 timer circuit that I am using:

enter image description here

This is the LM386 circuit I am using:

enter image description here

I have connected the output of the 555 timer to the 10k potentiometer.

If I connect the 555 timer part of the circuit directly to the speaker, I am able to use the 1M potentiometer to adjust the frequency and it works. Once I move the positive end of the speaker to where it’s supposed to be, I get nothing. No sound or anything. Why does this happen?

JRE
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Tara
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    Please provide schematics. We can't guess what parts you are using and how you connected them together. – Justme Mar 03 '22 at 17:19
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    You haven't shown any circuits. Please edit your question, there is a built in schematic drawing tool while editing you can use. A picture of a breadboard is not very helpful. If you want others to spend time helping you, please put in more effort. – evildemonic Mar 03 '22 at 17:28
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    You can use [Edit] and CTRL+M to access the built-in schematics tool. – Velvel Mar 03 '22 at 17:29
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    I'd bet that: a) the 8Ω load of the speaker is too much for whatever you have it plugged into, or b) the LM386 is incorrectly wired. Please edit and attempt to draw a schematic of how the components are connected. – rdtsc Mar 03 '22 at 17:58
  • how do you know that it is not outputting any sound? ... just because you cannot hear anything, it does not mean that there is no output – jsotola Mar 03 '22 at 19:41
  • I just added the schematics. I thought they uploaded the first time. I checked the voltage across the speaker and it was 0V. When sound played, it was around 0.04V. – Tara Mar 03 '22 at 20:47
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    Are you sure your C5 is 220uF? Kind of silly having all that gain (30+ dB) since the input is at supply voltage levels to begin with. – Spehro Pefhany Mar 03 '22 at 20:57
  • I'm not seeing anything obvious in the pictures, I would suggest checking that your connections are good, especially the pots, those have a tendency to not seat well in a breadboard. Of course there's always the possibility that your LM386 is just bad. – GodJihyo Mar 03 '22 at 22:17
  • Have you got pin 1 of the 555 grounded? –  Mar 03 '22 at 22:54
  • FYI, this circuit is not like a theremin. First you need touchless sensors, where your hand movement affects the sound frequency and level. Second, the output waveform should be sinusoidal (& maybe just a touch of even- or 2nd-harmonic distortion). The 555 outputs a square-wave which sounds like a "fuzz-tone electric guitar". – Rich S Mar 04 '22 at 19:18

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