Re: loop antenna question...

HI Cecil and the others...
How long ....
This is one of the things I would have to research if I was interested on
one...
In my imagination.. I have been thinking of these loop antennas as being
sort of a very large coil of wire as the input tuned circuit of the first rf
amplifier...
As the coil gets larger, in diameter, you need fewer turns.... So, by
extension, if you had a large diameter tuned circuit, let say 10 feet, you
would need very few turns... Unfortunately, .as well any tuned circuit, you
need a parallel capacitor... As you changed frequency, since we normally
change the capacitor, you have to remotely change the parallel capacitor...
Ok.... So you have this rather large loop, inductor, and you have it's
parallel, capacitor you have to peak them (I believe I have already said
that).. Now. since our cable usually comes in 50 ohm impedances.... you have
to transport this weak signal to the radio, you have to use a split
capacitor.... the full capacitor is in parallel with the coil.... The ground
capacitor, of the two series capacitors, is adjusted to give the proper
match to the cable and the series capacitor is the parallel to the coil, you
have a very marvellous network of two capacitors, needing separate tuning to
keep this overall loop tuned...

A lot of work.... I just hope this loop antenna system can be used in both
transmit and receiver... (just my initial opinion)....

Any further thinking on this subject... you have my attention...

Larry ve3fxq



"Cecil Moore" <w5dxp@xxxxxxxxxxx> wrote in message
news:1126360020_6099@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
> larry wrote:
> > I might consider it...for 80 or 40...
>
> How long is the loop in wavelengths?
> --
> 73, Cecil http://www.qsl.net/w5dxp
>
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