wrote:
Tom,

I just modelled that coil in EZNEC and it was self-resonant at 7.5MHz
- very close to the Corum model prediction of 7.4137MHz.

Interesting that both EZNEC and the Corum are wrong and by the same
amount!

Did you guys agree on the same ground plane? The self resonant
frequency of my 75m Texas Bugcatcher coil is very different
on my insulated wooden work-bench vs two inches above my GMC
pickup.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Cecil,

I tried mine above Perfect, Mininec Average, Mininec Salt Water. Self
resonant frequency was the same in each case.

Steve G3TXQ



On May 9, 10:49*pm, Cecil Moore wrote:

Did you guys agree on the same ground plane? The self resonant
frequency of my 75m Texas Bugcatcher coil is very different
on my insulated wooden work-bench vs two inches above my GMC
pickup.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com

Cecil Moore wrote:
wrote:
Tom,

I just modelled that coil in EZNEC and it was self-resonant at 7.5MHz
- very close to the Corum model prediction of 7.4137MHz.

Interesting that both EZNEC and the Corum are wrong and by the same
amount!

Did you guys agree on the same ground plane? The self resonant
frequency of my 75m Texas Bugcatcher coil is very different
on my insulated wooden work-bench vs two inches above my GMC
pickup.

I followed Reg's advice and hung mine from the ceiling with a thin
thread.
73,
Tom Donaly, KA6RUH

Tom Donaly wrote:
I followed Reg's advice and hung mine from the ceiling with a thin
thread.

That would certainly make it act differently
than over a good ground plane.

Where was your ground/counterpoise? Which self-
resonant frequency did you see? 1/4WL? 1/2WL?
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com