[Elecraft] Diversity receive versus QRM eliminators

[Alan - G4GNX]

Hi Gernot.

I use an LZ1AQ double mag loop (rotateable) to null out as much hash as 
possible. This feeds the RX Ant In input on the K3S. I also have an MFJ 
Noise eliminator which is also inline, using the LZ1AQ as the main (RX) 
antenna and I've tried a couple of antennas (including my HF vertical) 
as the 'noise' antenna and I don't find any noise suppression by phase 
elimination with the MFJ. I've yet to try a mini-whip antenna as the 
'noise' antenna. I actually wonder if the MFJ unit is faulty, as I've 
heard that other people have at least noticed a small difference when 
using it. Once/if I get the MFJ untit to work, I may then buy one of the 
more expensive noise eliminators.

73,

Alan. G4GNX


------ Original Message ------
From: gt-i at gmx.net
To: "Elecraft Reflector" <elecraft at mailman.qth.net>
Sent: 29/06/2020 18:18:30
Subject: [Elecraft] Diversity receive versus QRM eliminators

>Hello all,
>In a recent rush to eliminate urban noise I bought an QRM eliminator.
>The working principle is to null out signals by shifting the phases of
>two antennas (one main/tx and one rx). I can see the effect sometimes,
>but it is not the holy grail for all types of QRM. I still don't get rid
>of the PSU/LED/plasmaish noise here, sometimes the S/N is a bit better
>but maybe thats my inner impression to justify buying this thing.
>Now, I do wonder how this differs from diversity receive, effectively
>versus local QRM.
>Note I have a 10m vertical as the 2nd ant, while the main ant is horizontal.
>Any thoughts or hints ?
>tnx 73 Gernot DF5RF
>