Roger
What you are using is a vertical grounded LOOP. I
have made no attempt to receive DK7FC because I do not have the time to waste
waiting for a 600 sec dot or longer transmission. I am QRL on all the
other amateur bands on CW and SSB plus so many other interests beside amateur
radio.
also
my soldering iron seldom gets time to cool with the
building projects that are in hand.
g3kev
----- Original Message -----
Sent: Tuesday, December 14, 2010 7:10
PM
Subject: Re: LF: BODGE ANTENNAS
Mal,
Please, I make no magical claims for the
earth electrode antenna I use. All I say is that, in certain circumstances, it
works rather better than one might expect both on RX and TX on
VLF/LF/MF.
In my view it does work as a loop antenna on 136 and
500kHz with the loop area being determined by the soil conductivity (lower
conductivity, bigger loop area). The very fact that it is low-Q does
suggest loss. Yes, a fully "in the air" loop works better on both 136 and
500kHz. On 8-9kHz it is far less clear if this is acting as a loop or just a
voltage potential in the ground. Making an efficient "in the air" TX loop at
8-9kHz may be a challenge.
I've managed to receive DK7FC on 8.97kHz -
have you? - and this was using the very same earth electrode system being used
for my earth mode experiments, and for recent tests on 500kHz. A "proper" loop
antenna would have yielded several dB improvement in received signal level on
8.97kHz I do accept.
Again, all I am claiming is the structure is worth
trying in some situations, not that it works by some sort of magic potion that
has been fermented in my garage.
73s Roger
G3XBM
On 14 December 2010 18:45, mal hamilton <[email protected]>
wrote:
I am of the opinion what some on here describe
as Earth Mode antennas are BODGE antennas.
Old timers cannot be fooled but it is very
misleading for New comers to LF/MF
G3KEV
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