Today channel 11 no longer comes in. I rescanned for channels and other channels that never came in before came in. Do antennas just suddenly go bad?

I want Jeopardy! back.

I experience the same thing, one day I have certain channels and the next day they disappear, sometimes they come back but not on the same channel. Weird and I don't know the reason but it's not your antenna

Maybe one of the capacitors in the little rf amp went bad changing the reception frequency of the antenna.

It's a cheapie so I don't care if I have to replace it.

If there was another way to watch Jeopardy! I'd do it.

If the antenna is outdoors, wind may have blown it to point in a different direction. That happens with mine.

How's the weather there? Could it be "skip"? An old CB term when you could pick up conversations from areas farther away. Your car radio experiences this sometimes as well. I was listening to a station from Philly but my radio was picking up a broadcast from West Virginia!

That's happened here before and it turned out to be transmitter equipment problems. Contact the station for a sanity check.

The digital OTA stuff still pisses me off.
So much more difficult to get channels.
Eventually I will get to putting an antenna in the attic and feeding all the coaxials in the house. But for now I have an antenna on each TV except one.
That one is in the spare bedroom in a basement with no windows. It is hooked to nothing and gets more channels and better picture than all my other TVs with antennas.
Makes no freaking sense.

For me it's seasonal, channels I get in the winter, I don't get in the summer. I assume due to leaves on the trees?

I also notice I get more channels when it's raining, which I would have thought would work the other way.

 
There is no substitute for an outside antenna and the hawk booster. We pull in all of the PHX stations, 68 miles away, with this setup.
 

 

quote:

Originally posted by mark123:
Today channel 11 no longer comes in. I rescanned for channels and other channels that never came in before came in. Do antennas just suddenly go bad?

They do, but that's not symptoms characteristic of an antenna going south.

quote:

Originally posted by mark123:
Maybe one of the capacitors in the little rf amp went bad changing the reception frequency of the antenna.

That's not how that works, either.

It would help if we knew what market you were in (e.g.: Philadelphia, Pittsburgh, etc.) and what kind of antenna you have.

You can go to TV Fool and find out what stations you should be able to receive, where they are, what kind of antenna you would need for each, etc.

There is going to be a major shift in TV stations, called a "repack," starting soon, but it's not supposed to start until September of this year.

Some stations have chosen to shut down their own transmitters to "host" on sub-channels on other stations, so you might find your NBC affiliate has chosen that route. (A CBS affiliate in Lansing, Michigan, went that route.) Others have chosen to turn in their licenses and go off the air entirely. Some of those latter stations have done that, already. (The Flint, Mi. PBS station we used to watch went that route and shut down the end of April.)

If you remember your NBC affiliate's call-sign, you should be able to enter it into Wikipedia to find out where it's gone.

quote:

Originally posted by petr:
How's the weather there? Could it be "skip"? An old CB term when you could pick up conversations from areas farther away. Your car radio experiences this sometimes as well.

Those are at much lower frequencies than TV. AM radio is 535KHz to 1700KHz and CB radio is around 28MHz. For TV: VHF-Lo, which is currently not in use (though see below) sometimes does that. VHF-Hi and UHF definitely do not.

quote:

Originally posted by Black92LX:
The digital OTA stuff still pisses me off.
So much more difficult to get channels.
Eventually I will get to putting an antenna in the attic and feeding all the coaxials in the house. But for now I have an antenna on each TV except one.

Well, hold on to your hat, because it's about to get worse.

In the repack they're actually going to move some stations from UHF down to VHF-Hi, and even move a few stations back into (the currently unused) VHF-Lo. All those people who went out and bought UHF-only "HDTV" antennas may suddenly find themselves missing a whole crap-ton of channels. (E.g.: The popular Mohu Leaf in my experience did not work well in VHF-Hi.) And even some with UHF/VHF-Hi "HDTV" antennas may be in for a surprise when one of their stations is moved into VHF-Lo.

The only good news in all this, well... sometimes... for some of us, is the really difficult UHF stations that are way up at the high end of UHF are all being moved down. E.g.: All the moves in my market should improve everything for everybody around here. Probably. Maybe.

quote:

Originally posted by Black92LX:
That one is in the spare bedroom in a basement with no windows. It is hooked to nothing and gets more channels and better picture than all my other TVs with antennas.
Makes no freaking sense.

Yeah, well... welcome to "modern" broadcast TV.

About the time we went digital everybody abandoned VHF-Lo, and many even left VHF-Hi, for UHF space. And everybody's power dropped, because digital theoretically doesn't need as much power as analog. (This is the TL;DR version of what happened.)

This brought us to what you're experiencing, Black.

As somebody in another forum noted:

quote:

The only thing that counts are the coverage plots, which are typically not revealed by the antenna makers to avoid confusing the customers or some excuse. But you can find theoretical computed and actual tested plots for most antenna brands and all popular antenna types online, so it's not a total mystery. But for ATSC 1.0 there's not a lot the average consumer can do with antenna selection to increase reception, since it's many orders of magnitude more important where you are and where you put it than how it's designed.

I'd add: And sometimes not even where you put it. I have a Winegard FlatWave Amped that's at the "wrong" corner of the house that sometimes out-performs the high-performance rooftop antenna I have that's line-of-sight to most of the towers. Antennas, transmission lines and propagation theory and practice were things in which I specialized, in the past, and I can't make sense of it.

But wait! It gets better!

It was expected the abandoned VHF-Lo would be used for <somthing>. Plus they weren't sure DTV would work well in VHF-Lo. Well, it turned out that high UHF was more needed than the space freed up by moving stations out of VHF-Lo and I guess they found DTV would work down their, so now they're re-shuffling everything. (Thus "repack.")

N.B.: VHF-Lo is quite susceptible to noise. DTV signals and noise are not a good mix. I think it remains to be seen just how well DTV really works in VHF-Lo.

Yes, it's a clusterfuck. Your FCC at work.

So good luck, y'all.

References:
TV Fool (will tell you what you can currently get--probably)
RabbitEars Repacking Tools (will tell you what's moving where)
FCC Announces Results of World's First Broadcast Incentive Auction (The PDF document DA-17-314A1.pdf has all the gory details. Paragraph 64 has the repack timetable.)

quote:

Originally posted by henryaz:
There is no substitute for an outside antenna and the hawk booster. We pull in all of the PHX stations, 68 miles away, with this setup.

Like I said: There are no guarantees. I have an antenna not unlike yours, and my stations are mostly 10-16 miles away. One is 40. Yet some of them regularly give me grief. Yes: It makes no sense. Not to me or anybody else who's studied it.

Nice capture of the bird, btw

This message has been edited. Last edited by: ensigmatic,

For several weeks, tv stations in my area have been running commercials along the lines of "If you receive our channel over the air, please know we are moving to channel such and such as of some date and you will have to rescan.

If you are on comcast, dish, you will not have to do anything."

So perhaps your area got caught up as well. I didn't pay much attention as I'm on cable.

You can call the station and ask if engineering has made any changes in the signal or strength. They should be able to answer. I think your channel 11 might be WPXI.

Also, check both your antenna and coax. They both degrade over time. If I'm right about your channel 11 station, you have a couple of stations that are still on high VHF, so any replacement antenna you decide to buy needs to have both VHF and UHF coverage.

Check out http://rabbitears.info, then click on the market data.

I rescan my OTA channels periodically, sometimes I may lose one and sometimes I may gain one.

I have an antenna rotor on my antenna and that works great for fine tuning the weaker channels.

quote:

Originally posted by ensigmatic:
......... N.B.: VHF-Lo is quite susceptible to noise. DTV signals and noise are not a good mix. I think it remains to be seen just how well DTV really works in VHF-Lo..........

Good post.

Just wondering, What type of noise are you referring to?

I'm under the impression that VHF-Lo would be better for DTV in suburban and the somewhat rural areas. Refraction being the main advantage, which is tougher the higher you go, therefore Slightly better in hilly areas, around some objects, etc.

However, for VHF-lo, a larger outdoor antenna will become even more important for fringe (weak) areas. Gain is your friend, and you can't just get that from some smallish indoor thing on VHF-Lo. VHF-Lo antennas are larger for the same gain compared to UHF amtennas.

quote:

Originally posted by radioman:
Good post.

Thanks!

quote:

Originally posted by radioman:
Just wondering, What type of noise are you referring to?

Name something

Seriously. VHF-Lo (real/actual channels 2-6) is 54MHz to 88MHz - between the top of the Amateur Radio 6M band and the bottom of the FM broadcast band. So there are those two sources. Some people will have to become re-acquainted with FM traps.

Also, like the difference between AM radio and FM radio, not all of which is because of modulation and signal polarization, frequencies that low are more susceptible to spurious noise from electrical appliances, and particularly industrial equipment.

VHF-Lo is also susceptible to atmospheric phenomena such as ducting.

quote:

Originally posted by radioman:
I'm under the impression that VHF-Lo would be better for DTV in suburban and the somewhat rural areas. Refraction being the main advantage, which is tougher the higher you go, therefore Slightly better in hilly areas, around some objects, etc.

Yeah, but refraction can also create serious headaches, especially for a digital protocol that's "all or nothing," which ATSC is.

quote:

Originally posted by radioman:
However, for VHF-lo, a larger outdoor antenna will become even more important for fringe (weak) areas. Gain is your friend, and you can't just get that from some smallish indoor thing on VHF-Lo. VHF-Lo antennas are larger for the same gain compared to UHF amtennas.

Yup.

I need to digest ensigmatic's post, but just wanted to chime in that I have been having similar problems here in Milwaukee with all the OTA network stations I've been picking up with an antenna since we cut the cord. In the last several weeks that have all gotten very spotty, but the NBC affiliate is particularly bad.

quote:

Originally posted by bigwagon:
I need to digest ensigmatic's post, but just wanted to chime in that I have been having similar problems here in Milwaukee with all the OTA network stations I've been picking up with an antenna since we cut the cord. In the last several weeks that have all gotten very spotty, but the NBC affiliate is particularly bad.

This is entirely different from what Mark is experiencing. Your problem does sound like it may be antenna-related.

But first I'd like to ask: When did you cut the cord? When did you start doing OTA TV?

The wife was home today so she rescanned and channel 11 had returned. Hmmm.

quote:

Originally posted by mark123:
The wife was home today so she rescanned and channel 11 had returned. Hmmm.

See my comments, above, re: "Repack"

Some stations are beginning work on this, which may sometimes necessitate them briefly reducing power or shutting down entirely.

Direct exposure to tens-of-thousands-of-watts of near-microwave frequencies from mere feet away is generally unhealthy

quote:

Originally posted by ensigmatic:


Direct exposure to tens-of-thousands-of-watts of near-microwave frequencies from mere feet away is generally unhealthy

Some of the stations here are running 1 Million watts ERP. Yes, that's ERP, which is the result of antenna gain, and not what's actually out of the transmitter, but even so, 1 Million watts sounds like a lot.