Does Sunlight Affect OTA Signals?

For the past four or five days I have been experiencing a total loss of OTA signals during daylight hours. The weather has been clear, with perhaps some high level clouds and light or no wind. There are no obstructions between my antenna and the location of the transmitters which are approximately 35 miles away. My antenna is only about 6 feet off the ground.

Normally, when I perform a channel scan I get about 32 channels - all with five green bars. That’s my “normal” day-to-day experience. However, this week, during the day I’m getting the “weak signal” message on EVERY channel and unable to watch any channel. So I do a channel scan and it finds ZERO channels. Then in the evening, after the sun goes down, when I do a channel scan it will find all 32 (or so) channels - all with strong signals (5 green bars).

For consistent high quality reception I know I will need to mount the antenna much higher, and that will hopefully be completed within the next few weeks. But I can’t understand how I can get 32 channels with great signal quality during the evening/night, and on some days (not all) I get zero.



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It’s normal to get better reception at night. At 35 miles away you likely want an outside antenna or attic antenna with an amplifier. The range you see on antennas does not reflect reality. Often in perfect conditions antennas can’t do what they claim. Look up a few Antenna Man videos if you want to do a little research.

Thanks for responding. Improvements in antenna placement and quality are on the way, and hopefully that will result in more consistency. Meanwhile, I’m just amazed at the enormous range in signal strength - from excellent signal to none. :slightly_frowning_face:

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The sun, brings daytime, there is more activity and opportunities for various activity causing interference. Randomly, from time-to-time I loose a channel, often briefly… for no apparent reason.

To go from something to nothing for every channel? This does seem extreme. There are occasional post from users discovering something specific causing interference. Here’s an obscure example:

several users figure out the hard way too much amplification isn’t good.
After some time I discovered, after a lightening strike on the power line transformer, the power supply for my landscape lights screwed up one single channel.

Thanks for your input. I hadn’t thought about “environmental changes” within the house. At the momment I can’t think of anything that could be “different” over the past few days and/or day vs. night, but I’ll definitely spend some time thinking about it. I didn’t realize such simple things could cause so much trouble. Thanks!

I actually had a CFL bulb that was going bad, and it affected up my wifi. So you would be amazed what some simple thing could mess stuff up

Sunlight alone should not be a big factor in the TV frequency range. Interference is a possibility. Do you have a new model LTE filter (one for post repack)? Take a look at a Televes preamp at the antenna. They have a new model, but I have the older one that is a combiner and Amp. Televes has AGC, which is unique to them (but an incredibly obvious solution to TV and a simple add in). You get the gain you need independently on UHF and VHF. Look at your coax. Quad shield only. Look at connectors. All the coax and connector issues are subject to RF interference. If a UHF transmission source operates during the day it may screw you up. Look at FCC ULS database by address and see if you live near a ham radio operator. Highly unlikely they cause interference, but they can help you find it. Part of the hobby.

Apparently a lot of things can affect signal strength. I had no idea…

Thanks Mike. This whole world is a lot more complex than I thought!

These examples do happen, but are generally less likely to be an issue.

As previously noted, you first need a good setup, primarily antenna - antenna placement is just as important and an adequate one.

If you don’t need an amp or pre-amp don’t use it, a good quality signal is… good enough. Here’s a post with an easy to understand explaining the difference.

I disagree on the preamp. This case, for whatever reason, appears to be a marginal signal. At that range marginal is probably expected. He will be adding additional coax when he raises it. A preamp with AGC will not over drive the signal.
Finding interference is always difficult. We in ham radio use Signal analyzers if available but often a portable AM radio to get an idea. Tune between stations and listen to the static level. Crude but often effective. An LTE filter is often built into a preamp, but you need the newer one that filters down to 600mhz.
Power supplies are a huge problem for rf. Every CFL or led light has one. Any wall wort, etc. No small appliance uses a transformer anymore (quiet) they use cheap Chinese switching power supplies which often generate huge amounts of RF.
In this case, time of day is maybe the key clue. The totally random stuff is much harder.

Thanks. My current setup is exactly what your “Outdoor Installation” diagram shows. However, it does not include an LTE filter. Is that for cell phone signals, or something else. I’m not sure why that would present a problem during the day, but not evening/night. It’s probably something I should make sure is included in my “new” setup.

I keep working on it. Thanks for your advice!