Hi,
That small mag-loop has a small aperture and so all of the signals
delivered to your radio will be lower levels than from a bigger antenna
(in terms of wavelength. A preamp should improve the signal strength but
not improve the SNR over what you get with the loop and no preamp. The
mag-loop reduces the noise with it's high Q and decreased bandwidth and
those nulls contribute to reduced noise, too. I have excellent luck with
mine but there just isn't any silver bullet. The mag loop I use on 160
meters is four and a half feet in diameter. The receiver I use on 160 is
easily overloaded without some attenuation so the reduced signal levels
from the mag-loop are *ideal*.
73,
Bill KU8H
On 01/17/2015 05:06 PM, Ignacy Misztal wrote:
I homebrewed a magnetic loop for diversity reception with Hi-Z 3 el. in
K3. For perhaps up to 1000 miles the loop provides excellent separation
between signals from Hi-Z. But it hears distant stations poorly, much worse
than TX inv L. Based on earlier reports I expected the loop to be very good
for DX.
The loop is made from coax, is tuned and has a transformer. About 50 KHz
2:1 BW. A low-noise preamp does not improve S/N.
Any experiences with the loop here?
Ignacy, NO9E
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