I built (on perfboard) the circuit shown in the attached schematic. And, yes, I know the op-amp is antiquated and inadequate, and the LM386 sounds like a cheap clock radio . But even taking that into account, I can't get it to work properly.
It functions to a certain extent. I can hear output at the speaker when I make a really loud noise in the mic and have the volume control wide open, but the output is not very loud and is distorted. When the circuit is powered up and there is no input to the mic, I can hear a low volume, high pitched whine, which diminishes when there is input to the mic. I have checked and double checked the connections, but can't find a wiring error. I do wonder why R1 is connected to the R4/R5 voltage divider instead of to Vcc, but that's the way the schematic shows it.
Any suggestions are welcome.
Thanks.
It functions to a certain extent. I can hear output at the speaker when I make a really loud noise in the mic and have the volume control wide open, but the output is not very loud and is distorted. When the circuit is powered up and there is no input to the mic, I can hear a low volume, high pitched whine, which diminishes when there is input to the mic. I have checked and double checked the connections, but can't find a wiring error. I do wonder why R1 is connected to the R4/R5 voltage divider instead of to Vcc, but that's the way the schematic shows it.
Any suggestions are welcome.
Thanks.
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