28MHZ RDF antenna

[sp5it]

Hello.
New month, new challenge.
Can anyone point me to antenna I could use to locate noise source on 10m?
I got CB handie I could put antenna on and trace it.
I thought about small loop or ferrite rod antenna to get as much directivity as I can.
Any ideas/links guys?
MIke

 

[nomadradio]

Made one decades ago. A one-foot diameter loop of quarter-inch soft copper tubing. The ends of the loop were at the top with a mica compression trimmer cap across the gap for tuning. The coax shield attached to the very bottom of the loop. Center conductor attached partway up from the bottom. Seems to me it had a gamma-match type capacitor between the coax center conductor and the tap point on the loop.

I think. It's been a while.

This was a bidirectional antenna. You turned it for minimum S-meter reading, which would put the plane of the loop pointing at the signal source. Just couldn't tell whether it was ahead or behind you.

Don't remember where the plans came from. I'll have a look at some of the antenna books here and see if it turns up there.

73

 

[Tallman]

The answer you seek is in here: http://www.dopsys.com/products/HFDF.html

 

[sp5it]

The answer you seek is in here: http://www.dopsys.com/products/HFDF.html

Not really...

Covering the HF bands from 1.5 - 10 MHz

 

[Mudfoot]

I have good luck with a handheld yagi tuned to AM Airband around 118 Meg. A dual band HT with AM helps to attenuate when you get real close. Most HT's like that have attenuator built in. I have tracked down countless RFI sources that way.

On VHF AM, you will need to be within 75 yards or so. If the source is intense, then it can be heard further. I've always been able to find the source, mostly poles with many insulators or other hardware. Waving the yagi back and forth to null. Only thing more accurate would be an ultrasonic locator.

 

[Mudfoot]

This is what I use.

https://www.universal-radio.com/catalog/hamantht/3049.html

 

[Mudfoot]

When I had major powerline noise, this is the article I came across. I have talked to Gene many times. He's like a guru. I don't know if he's still kicking, but the dude is a braniac. I would email him various recordings of RFI and he practically identified everything just by the sound.

https://www.ctdxcc.org/powerlines/

Hell of a nice guy, very patient and most willing to help a guy out.

 

[KD2GOE]

hmmm this may help me too i am pegged 9s-units on 11 and 10m been like that 24-7 for over 3 weeks now.