I have been using my Cobra antenna for more than four years now, so you’d have thought I’d have seen everything. Yesterday, though was something different.
One of the things about an antenna that uses ladder line feedline is that the characteristics change when it gets wet. When this happens, re-tuning usually keeps me on the air. Of the three bands that I operate most often—30 meters, 40 meters, and 80 meters—30 meters requires the most retuning, then 80 meters, and 40 meters normally requires the least retuning.
Yesterday was different, though. It began raining late Friday night and continued throughout the day on Saturday, finally turning into freezing rain and snow late Saturday night. When I got on the air Saturday afternoon to make some contacts in the North American QSO Party, I couldn’t get the antenna to tune at all on 40 meters! I did manage to achieve an SWR of 1.5:1 on 80 meters and made a couple of contacts there, but the antenna tuner settings were way different from the normal settings.
I had never experienced such odd behavior before, and honestly thought that something was wrong with the antenna. Today, however, after the antenna had a chance to dry off, it all seems back to normal. And, as a bonus, band conditions weren’t too bad.
Electrical noise GONE!
I have a ceiling light in my dining room that has given me fits ever since I installed it. It’s quite a nice-looking light, but had 20 12 V, 10 W G4 halogen bulbs powered by a supply that put out all kinds of hash. The noise was so bad that I was unable to operate anything except FT8 on the HF bands.
Well, about a month ago, the power supply gave up the ghost. This was certainly annoying, but I took advantage of this opportunity to replace the halogen bulbs with LED bulbs like the one at right. I got both the power supply and the bulbs from Amazon. The trick was finding a power supply that would fit within the fixture, but with a little searching, I was able to do so. I re-installed the light fixture this afternoon, and am much happier now. It’s truly a win-win-win situation:
- The fixture consumes much less power than the old one. The halogen bulbs were 10 W bulbs. The new LED bulbs are rated at only 1.5 W.
- Despite the lower power consumption, the LED bulbs are brighter than the halogen bulbs.
- The electrical noise is GONE! Now, I don’t have to ask my wife to leave the dining room when I want to operate the radio.
30 meter band noise
Speaking of noise, do any of you have noise on 30 meters like the noise in the screenshot below?
30 meters is the only band where I see noise like this, and I’m wondering if it’s something local or more widespread.
Chuck K4RGN says
Yes, I came into possession of two-prong LED corncob bulbs that run great on 13.8 VDC from my Astron. I use them for lighting near the operating position. Sockets can be purchased online.
Dave New, N8SBE says
The biggest issue I had from the rain was that my inline connector going to my rotor near the top of the tower is just a block of Anderson Power Poles in a plastic housing which is not weatherproof by any stretch of the imagination. I put the plug assembly in a drip loop affair to discourage water from going down the rotor cable, but whenever it rains, the indicator for my rotor goes loopy. I had a hard time figuring out which way my antenna was pointed, unless I ran outside to double check. I use a computer-controlled rotor controller, so it was tough going for a while.
Fortunately, 20M gave out by about 6pm or so here, so when moved to 40M and later 80M, those bands are on a ZS6VKW dipole, which worked like a champ.
Signals on 40M and 80M CW were strong and persisted on 80M well into the wee hours. I gave up about midnight local, with about 9 hours of operating, since I took about an hour off around dinner time.
Didn’t make quite as many contacts as I’d like, due to my quad antenna aiming issues, but it was fun, nevertheless.