I made a tiny amp for my electric guitar with the LM386 chip and a small speakerI hooked it up just like the basic circuit in the datasheet, grounding the inverting input and leaving the gain and "bypass" pins open. I put a 0.1 uF cap across the power pins, and now it works great, with one little problem -- cell phone interference. Every so often my cell phone apparently gives a little shout-out to the system, whereupon the amp goes chirp chirp. When the cell phone rings, the amp goes nuts. I'd like to know where the interference gets in and what you do to put a damper on it.
15 years ago