Need Variable Frequency Oscillator Coil Design Help

Thread Starter


Joined May 10, 2008
Hi all,

Everyone is familiar with what a older 10 inch degausing coil loop looks like.

It works with 120 volts AC at 60 HZ and is used to degauss tv monitors.

I am trying to find a way to power that same type/size of coil loop whereas I can control the frequency from 0 on up to say 300 HZ.

Does any one have a simple 10 inch loop variable frequency oscillator circuit ( single transistor) thats fed with a low dc voltage power supply. Say 12 to 19 volts DC.

This loop then should be able to transmit this lower frequency a short distance. Frequency could be selected to whatever desired.

Any help will be appreciated.

Thanks, Tom


Joined Apr 20, 2004
A tv degaussing coil has enough inductance to keep the current through it down to a reasonable level. It's not frequency selective - it it operated off the 60 Hz line.

Your interest seems to be involved with inductive coupling so all you need to do is wind a coil and drive it with a transistor fed by a 300 Hz oscillator. The oscillator should be sine wave for best performance.

Here is a link to a freeware coil inductance calculator -