simple ham radio mic preamp for a HT

This is a very easy project.

 

 

 

Below is the basic plans for the pre amp, I tried several transistors and found the mps2222a worked the best for my application.  If you don’t have a mps2222a dont worry some of the others i tried were a mps3904 and a 2n4401, they both worked but the mps2222a had the best gain for my use (try any NPN transistors you have one of them should do the trick). Also i used a 12 volt to 9 volt converter but if you don’t have one a standard 9 volt battery will work fine.  The pre amp will work on a voltage of 6 to 9 volts, do not use 12 volts it will fry it!!!

For the project box I disassembled a old external floppy drive, just about any thing you can find will work..

 

 

 

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