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Converting speaker input to mic jack Answered


so i did this project of a spy mic using the lm386 amplifier, i took the schematic from afrotechmods, and it works. what i wanted to do was modify this circuit in such a way that instead of letting us listen to the voices of that time, i wanted to make it work on a phone, so i could record the audio in my phone, the original circuit diagram is attached. i also added my modified diagram. i just want to know if it will work, and i wont end up damaging my phone. what should i do to make this work right? the ''speakers'' in the original diagram are just earphones, no high power speakers. any help will be appreciated, thanks



3 months ago

1) Add two back to back 1 watt 5 volt zener diodes to protect your phone from damage..

I'm not sure if the phone van handle negative a -5 VDC !

2) Try again put a non-polarized capacitor 10 uF film capacitor in series with the phone jack and then place two 2.5 volt zeners back to back so the excursion will only be +-2.5 volts or only 5 volts..

3) Of course the best method would be to use a step down miniature audio transformer guaranteeing an AC signal at a low voltage without peak audio clipping distortion...

i understood most of it, but im confused about putting zeners ''back to back''. is this what you are suggesting in point no. 2?