How to use an AM radio to solve your VHF TV reception interference
Denny, I have a preamplifier HD Stacker setting at __________________ ave Effingham IL 62401 pointed about 77 degrees (as close as my old Boy Scout compass can get me) towards Terre Haute, IN - WTHI. I had never had any trouble picking up these channels in the past but now VHF channels 10.1 and 10.2 are not coming in clear. I checked my preamp, splitter, and lines leading to the antenna and found everything to be working properly. The TV stations say there has been no change in their signal since the digital switch a few years ago. I know 64 miles through woody terrain is a lot to ask out of an antenna but I got these channels for 2 years and now I don't. Any suggestions? Maybe a new building went up? The HD Stacker has been great - Jake
Sorry to hear channel 10 is giving you problems. It is the only VHF signal available. VHF signals are more susceptible to interference than UHF signals. Try tuning to channel 10 and unplug the amplifier from the electrical outlet. Does the channel 10 signal get even worse when the amplifier is unplugged?
If it is a localized VHF interference you may be able to find the interference with a portable AM radio. I know AM radios are getting rare but if you have one try tuning it to the lower end of the AM band. Listen for a buzzing or crackling noise. If you hear that it may be the interference and you can start moving around listening to the interference. When the interference gets louder you are getting closer to the source.
I tried what you suggested but no success with unplugging the amplifier. The signal drops out 100%.
I tuned to the AM and found interference only when the TV signal dropped out. When the TV flickered, so did the AM stations. Does that tell you anything?
My current tower is up about 27', I might be able to get another antenna up that is 50+ feet (not 100% sure of exact height but it is at least 50'), do you think that would be worth the effort?
Also, what low loss cable is suggested?
Raising the antenna won't likely help. The fact that when the signal drops you could hear interference on the AM indicates there is a localized VHF interference causing the problem. The next step would be to use the AM radio to find the location of the interference. It's likely in your house a very nearby. I just worked with a customer who was having a similar issue and he used the AM radio to find the interference. His VHF interference was a battery minder that kept a battery in his garage at full charge. Every time the battery charger kicked on his channel 13 would drop out. Because it's intermittent it may be difficult to find. Find the interference and eliminate it and the channel 10 signal will stop dropping out.
Turns out it was a heated pet blanket. I used my AM radio and went around the house/garage as you suggested unplugging anything throwing off my signal. The heated pet blanket fit the problem because it would come and go every few minutes as the blanket kicked on/off.
I guess the stupid cat will have to be cold when I want to watch TV.
Thanks for your help. Jake
Jake, that's great!!! In an attempt to keep the cat warm you could try plugging the pet warmer into a different circuit (if available) and maybe that would help.
I live in Kankakee, IL 60901 and am having trouble receiving the Chicago channels mainly channel 2.1. I get occasional pixellation on other channels but 2.1 is the main problem. I found your web page vhf reception interference and was wondering if you thought my problem was interference. I have one those 150 mile lava cheap antennas installed on my house about 25 feet above ground. The rotor no longer works but I have the antenna aimed northeast at the Chicago transmitters. Any advice would be appreciated. Thanks a million, Sherry.
There's always a chance that you are experiencing VHF interference but I doubt that's the issue. In your case the Lava antenna you have is likely not getting the job done. Even though the Lava antenna claims 150 miles the actual performance of this antenna doesn't come close to its claims. The 2.1 signal is rated weak at your location while all other Chicago channels are rated moderate in strength. To receive moderate and weak signals you will likely need an antenna with better performance. A very good choice for your location is the HD Stacker antenna. This antenna has an average of 3 to 4 times more signal gain than the Lava and should easily solve the 2.1 issue and the occasional issues you have with the other Chicago channels.
Take care and if you have any further questions please feel free to reply.
Hello again Denny,
With a little help from a friend we installed your hd stacker antenna last weekend. What a difference! With the lava antenna channel 2.1 registered 1 to sometimes 2 green bars on the TV signal meter. With the stacker it shows 4 solid green bars and sometimes 5. All other channels that displayed 2 to 3 bars with the lava now have a consistant 5 bars. Thanks for the advice and the great antenna. If anyone ask me about tv antennas i will surely send them to you. Monday night I watched hawaii five O for the first time without swearing at the tv lol.
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