On Sunday, November 16, 2014 7:39:53 PM UTC-6, FBMboomer wrote:

I have a Pixel magnetic loop with an A/B switch for receive using the
full size horizontal loop or the vertical Pixel loop. The full size loop
is almost invariably better on 75. On 40, the Pixel may or may not be
better. Mostly the full size antenna is better. On 20, 15, 17, and 10
the Pixel magnetic loop is better for me. Not always. But most of the
time. Having the A/B switch is really good for tracking QSB. For some
reason I do not understand, as the signal strength from the full size
loop decreases, the signal on the magnetic loop increases. This
phenomena is very consistent on the higher frequency bands.

The 80m horizontal loops I've modeled didn't seem too hot on the
upper bands. Pretty high angles for most all the upper HF bands.
So what you see sounds fairly normal. I just checked one model for
one at 30 feet, and none of the higher bands were doing all that great.
And the higher bands all had the max gain at fairly high angles.

DX
performance of the full size loop is very good from 20 meters on up.

Dunno. I don't think it's all that good, considering what you mentioned.
Usable I'm sure, but not great by any means.


Perhaps the fact that the antenna is resonant with no tuner on 20, 15,
and 10 may have something to do with this. I have read that the angle of
radiation from this loop is lower on the higher frequencies.

Lower than 80m, but not too low vs better antennas for those bands.


My magnetic loop receiving antenna has a 30 db preamp. Even with this
preamp the noise floor is always lower than my full size loop. My S
meter invariably shows the noise floor at 0 on all bands.

Normal for a small loop. Doesn't mean much. Only the s/n ratio really
matters. As long as you have enough signal to bring the background noise
up when connecting the antenna, should be good enough.