[Lowfer] EAR and MP: loop and e-probe comparison

[Garry Hess]

Finally fixed my small loop antenna that had gone deaf over the winter. 
Problem was two-fold. It was easy to identify relatively high resistance 
in the cheap RG58 feedling and replace it with larger 9913 cable. 
Unfortunately, reception was still erratic and nulls appeared then 
disappeared. Finally identified the problem - the mast pipe was slipping 
inside the rotator so the loop wasn't pointing where the readout 
indicated. That was easily fixed with a bolt through the rotator 
clamping plate and the mast pipe. Such a bolt is standard with a 
Tailtwister rotator but was left out because the wind load was so small. 
Didn't figure on the conduit mast pipe being so slippery. It wasn't a 
year ago but that was then. Anyway, lessons learned were don't use cheap 
coax and have a spotter to make sure the rotator is really rotating the 
antenna.

Attached are comparisons between the 3' loop and a Clifton Labs e-probe. 
The loop is run through the auxiliary port of a mdified MFJ noise 
canceller so the gain can be adjusted to match the main e-probe port. 
Both EAR and MP are nice daytime signals.
-- 
73, Garry, K3SIW, EN52ta, Elgin, IL
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