I called it the FoxBox Receiver or FBR


I started with TRF style ARDF receivers back in 1991 for 2m and 70cm bands, they were WIA kits. They worked ok if there were not other transmission with in the band with of there sniffers.

I also use to use transceivers I had and a stepped attenuator to try and reduce the signal. It didn’t really work too well if its super strong. I tip I found was try and and direction find the harmonic of the signal as it way more reduced. I could write and article to this.

Another solution I had was a 2Mhz oscillator with mixer. Basically you use what ever receiver you have and tune 2MHz down or up to heterodyne the designer signal. the oscillator buffer would have a gain control. this worker quite well.

You can buy direction finding radio or it was expensive commercial stuff.

Being a ham we would modify and receiver, A Tandy scanners was ideal with the bigger tuning range.

More to follow