[AMRadio] advice on el cheapo elecret mics

k0ng at inebraska.com k0ng at inebraska.com
Wed Dec 13 20:17:51 EST 2006

Vince: If your electret contains the FET follower inside, the typical  
source impedence of the FET is about 1.5K to 3.0K Ohms. I usually AC  
couple the output
(with say a 1 uF cap observe polarity carefully) to a 5 to 10K load.

Usually anything from a 1.5 V battery to a 6 V battery or well filtered supply
will work (I usually put a few K Ohms in series with the supply.

If your supply lines are long, it is best to put a 1 uF cap and a .01 uF cap
across the electret supply input and ground.

They do love to hum so shield well.

Good Luch, Charlie,  K0NG

This message was sent using IMP, the Internet Messaging Program.

More information about the AMRadio mailing list

This page last updated 15 Dec 2017.