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FBMboomer · July 3rd 14, 10:20 PM posted to rec.radio.amateur.antenna

On 7/1/2014 8:54 PM, wrote:
On Tuesday, July 1, 2014 1:51:23 PM UTC-5, FBMboomer wrote:

I am afraid we are all guilty of that at times. I just bought a pixel

magnetic loop receiving antenna. At first blush I thought it was great.

Then I put together an A-B switch so that I can make a well thought out

review for e-ham. The loop has some advantages, especially during

electrical storm noise. However, it does not come close to equalling the

performance of a horizontal loop cut for the right frequency.

What do you mean by performance? You will have trouble getting a decent
null using a horizontal loop. And the easily steerable nulls are 90% of the
reason to use a small loop.
But I only use small loops on low frequencies.. IE: LW to about 2.5 mhz or
so.. AM-BC more than anything, but I've used it on 160m at times.
A small loop can make an offensive ground or space wave signal disappear.
OK at night, but they are not near as effective nulling a sky wave signal
as a ground wave.

By performance, I mean the readability of a received signal. The signal
to noise ratio.

What I was trying to explain also was that my 75 meter horizontal full
wave loop does not receive as well on 20, 15, and 10. Generally!

When I operate on 20, 15, and 10, I use the pixel loop for receive. I
get a better signal to noise ration on these higher frequencies. I have
no idea why.

40 meters is kind of a crap shoot. The 75 meter loop might work better
for receive or the magnetic loop. That is one of the reason I made an AB
switch.

I do not know, but I can surmise that my receive on 75 would be better
on the magnetic loop if I was using a dipole for my antenna. I had a
dipole up at my lot a few years ago. The noise level in town was
horrendous. It was locking me out of using 75 meters. So I am now
comparing the pixel magnetic loop to a full size horizontal loop. This
may be kind of an unfair comparison. Most people probably would be
judging its improved performance over a dipole. I am currently unable to
make that kind of AB comparison. I took my dipole down in favour of the
full wave loop. The performance comparison between the dipole and loop
was profound. (meaning at least 10 db better S/N.

And yes, BC band performance is better than my 75 meter loop.