If you have nasty and persistent local Electical noise ie from arcing
insulators and nearby electrical crud from devices and a constant s9 or strong
noise floor the mag loop will work wonders only because it can null the
strongest of the noise (or all if in same direction) and present a superior s/n
situation. I've seen the tiny indoor loops do that too. The mag loop is
completely omnidirectional in both vertical and horizontal planes except for
the two end nulls so its no match for a full k9ay or terminated loop, flag,
pennant etc which has a lot more vertical plan discrimination however they
can't really null that strong very local Electical crud.
Sent from my iPhone
On Dec 31, 2012, at 11:30 PM, "Richard (Rick) Karlquist"
<richard@karlquist.com> wrote:
> In rebuilding the station this year, I have been trying a lot of receiving
> antennas. My criterion was: does this receive significantly
> better than the transmit vertical. I tried some beverages without
> success. In the past they had been good at times. I tried a low 80
> meter dipole that I happened to have. That was somewhat useful.
> For the SP, I put up a low 160 meter dipole. It loaded up so well
> I could have used it for a transmit antenna. Surprisingly, it was
> only 10 dB below the 60 foot transmit vertical. I had expected 20 dB.
> But on receive, it was no better than the vertical.
>
> The big surprise was the receiving loop. This is the one shown
> on the cover of NCJ a few years ago. It was phenomenal for receiving.
> Signals that were barely audible on the vertical popped out of the noise
> on the loop and were Q5. I used it for the entire contest, occasionally
> checking it against the vertical. I don't like to
> think that certain antennas are magic but by golly this thing really
> works. I did rotate it for minimum power line noise, which ended
> up having it broadside to a power pole I have had trouble with before.
> It was also approximately broadside to VK6GX, but I had no trouble
> logging him around 1200Z. I appreciated not having to switch between
> beverages, which has probably caused me to miss VK's in the past.
>
> In theory, the loop should not be much different than a vertical.
> What explains this?
> I am thinking about trying it at 30 foot height instead of ground
> mounted. Has anyone tried this?
>
> Rick N6RK
> _______________________________________________
> Stew Perry Topband Distance Challenge coming on December 29th.
_______________________________________________
Stew Perry Topband Distance Challenge coming on December 29th.
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