A common question with new BITX40 owner is “Which microphone should I use?” People have used modified CB microphones, Baofeng microphones designed for HT’s, and various homemade microphones. The BITX40 comes with an electret mic element and a small switch to make a microphone with, but the switch is not very good. I purchased 10 small switches for use in various projects and I’ve used one of them for mine. For supplies, I used the included mic, some random stranded wire salvaged from various electronics, the aforementioned switch, an empty generic Airborne container, and the USB cable from a dead keyboard (a mouse cord works fine too).
The pictures speak for themselves, and so I’ll let them do the talking. Hot glue was used to hold down the mic element, and simple electrical tape provides grip. And a word of caution when cutting up the lid: Do it over a trash can! It contains silica gel beads that will go everywhere. What kind of mic are you using? Let us know in the comments below!