I had a Homer Simpson "D'Oh" moment last night, and I'm embarrassed to admit it. It's almost a Rookie mistake. One of those "Why didn't I think of that before?" moments. Also, one of those "I should have known better" moments.
I checked into the St. Max last night on 75 Meters. There was a lot of QRM from the Sweepstakes, but there was also a lot of QRN. Someone in the neighborhood must have been using something that doubled as an RFI generator. The noise level was noticeably up for the first time since I put the ferrites on my coax. The Net Control Station, Lloyd K3QNT, offhandedly just happened to mention he was being by bothered by some local QRN, so he installed a low pass filter in line and it greatly improved his situation.
Low pass filter? I have one of those!! Back in the Dark Ages before cable, it was almost mandatory if you wanted to avoid an angry knock on the door from a neighbor whose TV looked like a test pattern when you would transmit. When I moved to South Plainfield, and I went QRP, and I saw that all my neighbors were hooked up to cable, I put my low pass filter into storage. "Who was I going to bother?" was my rational.
But here's the reality which I totally overlooked. A low pass filter works both ways. It's a two way street! Just as it will prevent potential harmonics above 30 MHz from leaving your station ... it will also help in reducing higher frequency RFI from interfering WITH your station!
I found a coax jumper (way too long) in my junk box and inserted the filter in line. Voila! It didn't knock out all the hash, but it reduced it quite a bit. Every little bit helps. Over the long holiday weekend, I will shorten up the jumper.
Over this past weekend, no new DX. but I did work a bunch of POTA stations. I was hunting the H44WA Solomon Islands all weekend long, but they were never loud enough for me to be able to hear them answer me if by some odd twist of fate, they should hear me.
72 de Larry W2LJ
QRP - When you care to send the very least!