[TowerTalk] Unique Short Radial Challenge - N5OT Question

Mark Beckwith n5ot at n5ot.com
Sun Oct 21 20:37:07 EDT 2007


> Radials under the K9AY loop???


Careful now, you're talking to someone who doesn't get a lot of RF 
hocus-pocus.  All I know is K9AY says "a ground rod is usually sufficient" 
but I'm pretty sure he doesn't elaborate too much on what to do when a 
ground rod is not sufficient.

I don't know if my ground rod is insufficient, but I do know that with a 470 
ohm fixed resistor (not the 390 ohm resistor Gary recommends as optimum for 
160), I get fair results in the F/B department but might like to try for 
better results.  I'm "measuring" 10db or so F/B but not convinced of my 
measurements either - it could actually be better than that.  That's how 
much the S meter changes when I reverse the antenna, pointed at a signal in 
line with the loop (local BC station on 1400 kHz).

Also, I suspect my ground rod may not be sufficient because I have bedrock 
about 14 inches down so that's all the ground rod I have under this antenna 
at the moment and if "improving the ground" were as easy as, say, laying 8 
radials on the ground out to the circumference of the loop (about 17 feet) I 
would try that and see if it helped, since it's so easy before attempting 
the more obvious approach of fine-tuning the termination resistance.

Mark, N5OT 



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