Hi Alan,
The MFJ works very well as a noise eliminator only if the noise antenna is very close to the noise source, so that the noise is much stronger than the desired signals. If the noise antenna is receiving about the same signals as the main antenna the noise elimination function cannot work... 73 Frank W3LPL ----- Original Message ----- From: "Alan - G4GNX" <[email protected]> To: "Elecraft Reflector" <[email protected]> Sent: Monday, June 29, 2020 5:43:24 PM Subject: Re: [Elecraft] Diversity receive versus QRM eliminators 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: [email protected] To: "Elecraft Reflector" <[email protected]> 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 > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
