Hi Jerry & Topbanders, Doing the math from the info below:
AM 890 x 2 = 1780 KHz + 1730 KHz = 3510 <- - your 80 meter birdie. I hope this makes sense and helps solve the puzzle. As I noted before, it is probably generated off site by some rusty connection in a radio tower that is a nasty diode as well. 73, George, K8GG... > *I put the strap around the rotator today. I no longer have a birdie on > 1820. Not a trace of it on any antenna. Based on symptons, I can only > conclude it was caused by intermittent contact at the rotator bearings > or by intermittent contact at the bearing on top of the tower. Diodes > inside the rotator do not seem to be a problem.** > ** > **The strap had no effect on my 3510 spur, which means the mixer for > that one is somewhere else. That one is not a big problem because it > goes away at nighttime due to one of the stations being daytime only.** > ** > **The strap is 1/4 inch diameter twisted (not braided) stranded tin > plated wire, very flexible. Length is about 16 inches.** > ** > **Special thanks to Lloyd N9LB and Hank K7HP who had the correct answer.** > ** > **Jerry, K4SAV - happy camper* > > > On 11/2/2017 5:27 PM, K4SAV wrote: >> Likely all the spurs you see on 160 that are caused by AM stations >> will land on 10 kHz increments because the stations are spaced on 10 >> kHz increments. I identified one of the stations that was a big >> contributor to my problem and that was on 1730. I haven't found the >> other station yet. I expected the station on 890 to be a contributor >> since it is only 1700 ft from my antenna but I don't think it is the >> one. (It is a contributor to the spur that happens on 3510). >> Regardless of which stations are involved, the main problem is that >> the mixing is being created near my rotator, and probably inside it >> somewhere. I have to kill the mixer somehow. More than likely the >> stations are clean. It will be interesting to see if the same mixer >> is causing both spurs, 1820 and 3510. Fortunately the 3510 spur goes >> away at night because one of the contributor stations is daytime only. >> >> Interesting video by N8PR, but he is fighting a different problem from >> what I have, >> >> I do not have a strap around the rotator. That's worth a try. Thanks >> Lloyd and Hank. >> >> Jerry, K4SAV >> _________________ >> Topband Reflector Archives - http://www.contesting.com/_topband > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > _________________ Topband Reflector Archives - http://www.contesting.com/_topband
