power Mic 40db pcb etch (pix inside)

[9Lives]

This is a circuit I was mentioning on the previous thread but I added a couple ferrite beads and changed a couple values. I found the improved schematic on cbtricks of the cobra power Mic. (THIS IS NOT MY DESIGN. I JUST ADDED A LITTLE AND DESIGNED A LAYOUT/ETCHED OFF OF EAGLE CAD.) I solved my previous problem.. I had it hooked to the transmit pin instead of audio. What I did its spliced it in after the dynamic pot so I could use it as a pre-gain. And simply used the spot of the delta tune to attenuate the circuit. The trim pot is a 1k emitter variable resistor for the 2nd transistor to set the gain to the radio. Hellz yes.. pretty happy how it came out.

If any one is intetested in having one of these pcb PM . I can make more.

 

[680MAINE]

Nicely done, seems like you got it figured out. The proto type seemed like contact could have made a short b/w one of your ceramic disc capacitors and one of the electrolytic capacitors. Or it coulda just been the camera angle. Looks like a project I might try this winter.