Got to say Id keep it off and away from any earthed or partially losses object as it does affect the Q etc, and if the fence gets wet it will detune more -
8ft was the minimum height I used - just out of reach of the "animals" in Oklahoma and it would be 10ft in Alaska cos of the Moose...I used multiparalled loops to reduce the R but the loop conductors all told probably weighed 220 pounds.
As others have said - Im not sure of the power but there still can be a couple of Kv on the loop (at 1Kw say) and with the very high currents (30-50A) involved it reminds of car battery connections (or if your of my age - bus bar connection requirements in telephone exchanges) - then add a Kv or two.
- with a reasonable TX "largish" Low loss loop resonanted tuning thru resonance with an SSB receiver will sound like a tight 1.4Khz or tighter mechanical filter...well at 137 it did.
Laurence KL7UK
Date: Fri, 13 Aug 2010 16:53:07 +0100
From: [email protected]
To: [email protected]
Subject: Re: LF: A question about loops for 136 and 500kHz TX
Wow - not bad feed back in a few minutes! Thanks everyone for chipping in with ideas and links.
I guess my question was prompted by the results recently with the earth electrode antenna with the ground actually forming part of a loop antenna. The logical extension was to elevate the loop but leave the bottom running along the ground (in a wire rather than relying on the soil for the return path with its resistive losses).
If I may précis the responses here, you all consider this is not a good idea and recommend elevating the lower section a few metres. I can do this, running the lower wire along the top of the wooden garden fence (OK?) .
73s
Roger G3XBM
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