I was having a similar problem. Hopefully I can explain this clearly. I hit channel all the way through the channels and I have them all, when I channel up and it flips back to the beginning, I channel up or down and it only scrolls through my favorite channels. Anytime I channel up or down and it goes back to the first of last channel it changes from all channels to favorite channels.
What I have noticed is that channels are dropping because they are discovering a different rating. For example, local news will be TV-PG and then drops the signal to reset to Rating N/A and come back on - only to re-drop and re-gain another signal.
Have another tv (different brand) connected to the same antenna and have no problems.
Its the Favorite Channels option in Settings/TV input/antenna.. uncheck the favorites option. I think it's a stupid feature. This is a good example of a smart TV doing a lot more than it should. The original posters follow-up post clears it up, that's how I fixed it.. disable the "favorite channels" option. Somebody visiting This thread might have a different issue but I had the same exact issue as the original person.
For the issue where the signal goes in and out --> It could be that you have a USB plugged into back used for live tv pause feature. I used another USB stick I made sure to use the max TCL supports ( =>16GB) and you want to get a fast read/write speed, so just buy a USB 3.0 (32GB) stick. I say 32GB because although TCL supports maximum 16GB, when it's used by the TV it really is only using maybe 15.5, because of created partitions. So I say go with 32 GB so you get the full 16 they say they can support for Live TV. My problem was I was using a cheap old USB stick. They are not that expensive just make sure to get USB 3.0. Before spending money you can also take out your USB then insert to a computer, go into Computer or 'My Computer' in Windows 7, then right click the USB mass storage drive number that is for your USB and Format it in FAT32. This may not work, but if you're trying to save money it may be worth it. Once that is complete, take back to TV and see if issue persists. ***NOTE*** A Format will wipe out everything on your USB, and you'll want that because you'll want to give the Live TV all the space it can get to provide you with the full 90 mins of rewind time. If you want a USB to store pics and videos on to play on the TV, I suggest using another one just for that purpose. I experienced both of these issues above. I did not have any signal issues related to antenna.
Before I start asking about your setup in respect to antenna, I want to ask when you arrive at the channel (when it does show) how many bars does it show in lower left hand corner? Try a fresh channel scan (same area where you disable that favorite setting), its possible the frequency of that particular channel moved with all the changes lately with FCC. After scan, double check that fav option is unchecked.
4 bars is more than good. Do you have that USB thumb stick feature plugged in back and enabled, where it allows you to pause and rewind up to 90 mins? I had that feature until I started seeing it drop out like that every other minute, it happened especially when I was watching 1080p programs. My problem went away when I used another USB thumb drive or unplugged it.
Thanks, this worked for me. One additional point - when I go to settings - > hide settings, and scroll through the channel list, there is a viewer that shows the channel that I may want to hide - lo and behold, there are no blank screens. I can view and hear all the "missing" channels. This proved to me that it wasn't my antenna; there was something else going on.