Originally Posted by Calaveras
I was thinking recently that since my current antenna configuration hasn't changed for a long time time how stable all the signals from all directions are. I see the same sort of ups and downs on all the stations. SNRs are little changed over the long term. Even the most marginal stations are unchanged. If I do see changes in the years to come it'll probably be from growing trees.
I agree with Chuck. Signals vary quite a bit, especially those that are some distance away from here, but it's always within established limits. I'm seldom surprised anymore by what I see. For example, stations like KMAX and KQCA from Walnut Grove can vary from just above the cliff edge, like 16 dB SNR, to as high as 26 dB, but they very seldom drop out or get pixelated. KVOR has a lower range, from 13 to 20 dB, but their signal is always within that range. VHF stations KVIE and KXTV are more often below the cliff edge at 13 to 14 dB than not, but they can make drastic increases to 20 to 22 dB at times. But again it's all within the established range of signal strength.
One station that doesn't vary much at all is KEMO, transmitting from Mt. St. Helena. It's usually between 20 and 22 dB all the time.
The distance for Walnut Grove vs Mt. St. Helena is very similar... 62 vs 65 miles... but the difference is the terrain. There are few hills between here and the Napa Valley, while Walnut Grove is on the other side of the 1,000 foot high East Bay hills. Is hilly terrain more conducive to inversions than flat terrain?
Every once in a while I see channels 20 and 24 that transmit from the bluffs east of Red Bluff, which is about 175 miles from here line of sight, but I have never received anything from the Salinas/Monterey area to the south.