OTA Experts Please Help

Different amplifier designs react completely differently from one another, so one never knows.

Here's another question... Do you have LED's in the RV, and have you experimented with turning them on and off?, it could even be a neighbor..

Somewhere on here I did a post complete with pictures of the MASSIVE RFI generated from an LED lamp I was testing, and most of the garbage was square in the VHF-TV/ FM band

(later)
Heres why I asked. HERE is a link to the LED RFI test I did, and I remembered it correct. Channel 7 is among the worst when dealing with runaway RFI.

The LNA-200 has no gain adjustment. I really doubt it is interference as my neighbor has not been affected and I have never heard of problems in this semi remote area before.
Next time I go I will have to take a portable TV and do some testing at the antenna. I never tried it with the long run to the house without the amp so I don't know if the VHF should work without the amp. I think it has to be the amp or the balun on the antenna.

Do you gave a gain knob on that amp? If you have a SensarPro in-line anywhere, set it at 10 or below and see that that does. If you're not touching anything I think (from 3000mi away)that you might be getting whacked by a much stronger carrier nearby. These amps are fairly straight forward, often having only one transistor with lots of frequency select tuned circuits surrounding the one device. The point of all that is to pass the TV bands (usually including FM, but there may be a switch) and filtering all else out for possibly this reason.

FM licensees OFTEN have more than one transmit site that they locate their backup transmitter(s) incase of catastrophic failure at the primary, and they use them regularly. A little 5-10KW backup transmitter will fit prettymuch anywhere. Its possible you have a primary or backup causing these intermittent problems.

If this VHF is as strong as you say, try unplugging the amp closest to the antenna and see what that does

Is there something in this type of amp that you think could go bad overnight and cause it?
Another strange thing happened now that we are talking too much power.The day before I lost the VHF channel I did a rescan. I picked up 4-5 channels that I never got before. The next day it was back to the normal UHF channels and lost my 1 VHF. I had just thought it was very good weather conditions.

SCVJeff wrote:
Very strange.. I see that WWNY and another station are out there all by themself but that shouldn't cause any problems.. You mentioned a deep fringe pre-amp in the setup. If I had to venture a guess from 3000mi away I would say that something is swamping your preamp and shutting it down, I have this problem out here at the beach with my VHF being shut down by a local FM.. Can you turn the gain down or take it out of circuit?

You bring up a subtle point about over gain that a lot miss. You can actually loose a digital station by as you say swamping an amp.

Very strange.. I see that WWNY and another station are out there all by themself but that shouldn't cause any problems.. You mentioned a deep fringe pre-amp in the setup. If I had to venture a guess from 3000mi away I would say that something is swamping your preamp and shutting it down, I have this problem out here at the beach with my VHF being shut down by a local FM.. Can you turn the gain down or take it out of circuit?

I tried it with 2 different tuners. The one in the TV and with the OTA in the Dish satellite that feeds into the HDMI of the TV.
I checked with a neighbor to be sure the station was still on.
I am in 13420. The channel I lost is 7.

If this station is as strong as you say, it's pretty hard to break the antenna OR preamp that the VHF is gone and UHF remains. Can you check with another TV?

It is also remotely POSSIBLE that the VHF you are receiving is an analog LP that just converted to digital. Allot of them are doing this to preserve their place in the upcoming auction.

Out of curiosity, where are you located? I want to look at the maps

Contact the VHF station..They may have moved..
Checking out the LNA it is possible one of the amps went bad.. Try bypassing it for a few minutees as well.

I also found out that one of the cheap flat screens I just bought is not even capable to search for UHF only VHF. :R

The new TV's built in the last several years have a ATSC turner in them.
It picks up all digital UHF broadcast stations.

If yours doesn't then it is a NEW several years old TV. And you were ripped off.