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Old 9-Sep-2017, 7:19 AM   #1
Dagwood
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Odd thing has happened twice . . .

Hi. About a half hour ago (it is now 2:00 AM) all my channels went dead on both my TVs. I normally get about a dozen channels or so.

This same thing happened around a year ago, and I assumed something went haywire with the antenna/cable -- there's no way all those channels could suddenly stop transmitting at the same time. But the next day everything was working fine, and has ever since. And I've forgotten about it, til tonight when it happened again.

I did a search here before posting and found this thread about a preamp going dead.

I put a whole new system on the roof in 2009, including a new preamp and cable going to two TVs (I don't remember for sure the brand of the antenna and preamp, but I'm thinking Wineguard). One of the TVs was replaced two years ago, the second one was replaced a year ago.

Everything has worked flawlessly since it all went black the last time, then came back on by itself. Any idea how it "fixed" itself overnight, and has been fine for a year or more?

If it doesn't come back on by itself miraculously tomorrow, before I go fooling around on the roof, is there anything I should do first? What do I check besides obvious connections to see if they're tight?

I'm not young, and am not crazy any more about getting up on the roof, but do it when I have to.

Thanks in advance!
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Old 10-Sep-2017, 1:07 AM   #2
Dagwood
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FWIW: Both TVs worked as normal this morning.

Anybody got any answers or suggestions as to why, or how, this happened?
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Old 10-Sep-2017, 6:12 PM   #3
rabbit73
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Quote:
Originally Posted by Dagwood View Post
If it doesn't come back on by itself miraculously tomorrow, before I go fooling around on the roof, is there anything I should do first? What do I check besides obvious connections to see if they're tight?
You could check the voltage going up to the preamp.

What model is the power inserter that is down below?

Your previous thread has some background information that might help others to help you.
TV signal slowly degrading . . .
http://forum.tvfool.com/showthread.php?t=13158

At that time, your signal problem was caused by electrical interference.
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Last edited by rabbit73; 10-Sep-2017 at 7:03 PM.
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Old 10-Sep-2017, 9:41 PM   #4
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It could be a solar flare. Where do you live?


Quote:
Originally Posted by Terryl3 View Post
It's a big one

This mornings solar flare is the biggest one for many years, there have been reports in some areas of OTA TV and CATV signal loss, cell phone traffic has also been affected.

This flare has also affected HF radio signals and satellite signals.

http://www.swpc.noaa.gov/products/goes-proton-flux

http://www.swpc.noaa.gov/

It's the green line (I would have used the red one) you have to watch, as it is now above the dotted line, if it goes above the next line up then it may be time to get the lead underwear on.:eyecrazy

If it goes above the second line above the dotted line then we could see the AC power grid affected, it could cause (and in the past has) overloads and cause line circuit protection devices to trip.

This could cause wide spread power outages.:helpme

So if your missing out on the game, don't blame the station, there is nothing that can be done.


P. S. If it goes off scale then we will be back in the 17th century as far as technology.

P. P. S. It might be some good Northern Light viewing in some areas over the next few nights.
https://www.highdefforum.com/local-h...s-big-one.html

Google

https://www.google.com/search?source....0.qu8N5pVBc3I
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Last edited by rabbit73; 10-Sep-2017 at 11:05 PM.
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Old 10-Sep-2017, 11:39 PM   #5
Dagwood
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Quote:
Originally Posted by rabbit73 View Post
You could check the voltage going up to the preamp.

What model is the power inserter that is down below?
What is a "power inserter"?

Quote:
Your previous thread has some background information that might help others to help you.
TV signal slowly degrading . . .
http://forum.tvfool.com/showthread.php?t=13158

At that time, your signal problem was caused by electrical interference.
Ha, I had totally forgotten about that. I can't believe it was 4 1/2 years ago. I couldn't even remember the name of this site the other night, but I Googled around and recognized it when it came up.

Quote:
Originally Posted by rabbit73 View Post
It could be a solar flare. Where do you live?
I checked both those links; none of it meant much to me. I live in upstate NY, south of Rochester 30 or so miles, as the crow flies. Could a solar flare have been the problem?
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Old 11-Sep-2017, 1:14 AM   #6
rabbit73
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Quote:
Originally Posted by Dagwood View Post
What is a "power inserter"?
You said you had a preamp. A preamp needs power to operate, and a power inserter sends the power up to the preamp.

A preamp system comes in two parts: the preamp itself up by the antenna, and a power inserter down below. The power inserter makes it possible to send the DC power up to the preamp on the SAME coax that sends the signals down to the TV.



If something goes wrong with the power inserter, then it might not be able to send the power up to the preamp to make it amplify the signals.

It is possible to measure the voltage at the power inserter to see if the voltage is there without going up to the roof. Of course, that is only he first step in trouble shooting a preamp. The results of that test will determine what you need to do next.

Do you have a voltmeter, or do you have a buddy that can make electrical measurements?

http://dennysantennaservice.com/1136577.html

Quote:
I checked both those links; none of it meant much to me. I live in upstate NY, south of Rochester 30 or so miles, as the crow flies. Could a solar flare have been the problem?
Solar flares can knock out radio and TV signals. They can also knock out the power grid. You must remember the widespread blackout in the Northeast that started in Canada.

https://www.nasa.gov/topics/earth/fe..._darkness.html

https://www.inverse.com/article/3413...kout-nyc-earth

There has been loss of signals this week.

https://www.google.com/search?q=sola...iw=911&bih=345

So, it is possible, but it is more likely a problem with your preamp.
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Last edited by rabbit73; 11-Sep-2017 at 1:42 AM.
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Old 11-Sep-2017, 3:12 AM   #7
Dagwood
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Quote:
Originally Posted by rabbit73 View Post
You said you had a preamp. A preamp needs power to operate, and a power inserter sends the power up to the preamp.

It is possible to measure the voltage at the power inserter to see if the voltage is there without going up to the roof. Of course, that is only he first step in trouble shooting a preamp. The results of that test will determine what you need to do next.

Do you have a voltmeter, or do you have a buddy that can make electrical measurements?
Aha, yes. Mine is a Wineguard PS-1503.

I have a meter, and know basic electricity, but know nothing about how this system works. What/where should I check? Can this thing go haywire, correct itself overnight, be fine for a year or so, then go through the exact same cycle again?

If it's working fine, like it is now, should I expect a voltage reading to be off or would I have to wait til it goes out again?
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Old 11-Sep-2017, 7:44 PM   #8
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Quote:
Aha, yes. Mine is a Wineguard PS-1503.
Here is the Winegard troubleshooting video:
https://www.youtube.com/watch?v=ZNPb1XNBQSI

Quote:
If it's working fine, like it is now, should I expect a voltage reading to be off or would I have to wait til it goes out again?
Check the voltage now while it is working. If it goes out again, see if the red LED is ON or OFF.

You have an intermittent problem. I think you know how difficult that is------you have to catch it when it is acting up.

At this point, you don't know what is causing the problem. It could be the antenna, the balun between the antenna and the preamp, the preamp, the coax between the preamp and the power inserter (injector), the power inserter, or the power transformer. It could even be the signals.

Your job is to isolate the problem to one part of the system by substitution of known good components, even if it means a completely separate test antenna and coax.

I can't be any more specific because I don't know what your antenna looks like and I don't know what kind of signals you have because you haven't given us a tvfool signal report for your location. You can do a report here:

http://www.tvfool.com/index.php?opti...pper&Itemid=29

Quote:
I live in upstate NY, south of Rochester 30 or so miles, as the crow flies.
That might be somewhere near Geneso, Leicester, or Mt Morris.

Here is a report for Mt Morris. The Rochester signals aren't very strong, but WPXJ ION from Pavilion is strong enough to use as a test signal with a simple test antenna, if that is your location.
http://www.tvfool.com/?option=com_wr...e6a4f831e85205
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Last edited by rabbit73; 11-Sep-2017 at 8:45 PM.
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Old 16-Sep-2017, 3:52 AM   #9
Dagwood
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Quote:
Originally Posted by rabbit73 View Post
Here is the Winegard troubleshooting video:
https://www.youtube.com/watch?v=ZNPb1XNBQSI

Check the voltage now while it is working. If it goes out again, see if the red LED is ON or OFF.
Okay, transformer measures 29 V. and the "Ant" connection on the power inverter measures 16 V., both okay according to the video.

Everything has been working fine since last weekend, so I guess all I can do now is wait until it doesn't.

Thanks for the help!

EDIT:
Quote:
I can't be any more specific because I don't know what your antenna looks like and I don't know what kind of signals you have because you haven't given us a tvfool signal report for your location. You can do a report here:
Actually, I did that but it didn't "stick" for whatever reason. I will do it again.

Here is the link they said to post.

FWIW: Here is what I really have:

I live in a hole, with a hill between me and the transmitters. If these signals only go in a straight line (as I've read) then I am only getting them because they are bouncing off one of the other hills.

NBC, ABC, PBS always come in fine. CBS is normally fine, but if the antenna isn't aimed exactly it can be dicey, depending on the weather.

I only get FOX from around September/October until April/May. It is like this every year, and was the same even before 2009 when it was analog. I assume it has something to do with the atmospheric changes as the seasons change. It does not correspond with the leaves being on or off the trees.

Last edited by Dagwood; 16-Sep-2017 at 5:23 AM.
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Old 16-Sep-2017, 5:15 PM   #10
Tower Guy
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In addition to an intermittent electronics failure ithe problem could also be caused by interference. Is there anything electronic that you added lately?
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Old 16-Sep-2017, 8:34 PM   #11
Dagwood
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Quote:
Originally Posted by Tower Guy View Post
In addition to an intermittent electronics failure ithe problem could also be caused by interference. Is there anything electronic that you added lately?
Not since this problem as outlined in my last thread from 4˝ years ago.
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Old 17-Sep-2017, 12:23 AM   #12
rabbit73
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Thanks for checking the voltage to the preamp. If you have a problem again, check to see if the LED on the power inserter is still ON. as it should be, or OFF.

Thanks for the tvfool signal report.
http://www.tvfool.com/?option=com_wr...e6a4c5db6f4ec6
Quote:
NBC, ABC, PBS always come in fine. CBS is normally fine, but if the antenna isn't aimed exactly it can be dicey, depending on the weather.

I only get FOX from around September/October until April/May.
That description exactly matches your signal report. NBC, ABC, and PBS are your strongest signals, and CBS is listed just a little weaker than PBS. Fox is a lot weaker than CBS.

CBS sends 992 kW out of 1000 kW ERP in your direction. If you click on the CBS callsign in your report, this is what you will see:
http://www.tvfool.com/?option=com_wr...dALLTV%26n%3d4



Fox is much weaker because it has a very directional transmitting antenna that sends only 11 kW out of 320 kW ERP.
http://www.tvfool.com/?option=com_wr...dALLTV%26n%3d5


Quote:
I only get FOX from around September/October until April/May. It is like this every year, and was the same even before 2009 when it was analog. I assume it has something to do with the atmospheric changes as the seasons change. It does not correspond with the leaves being on or off the trees.
What you assume is correct; the seasonal change does make a difference. In the warmer weather, the Fox signal is not able to bend down to your location by refraction because the density of the air changes in warm weather.

Forum member tripelo says it much better than I can:
Quote:
Originally Posted by tripelo View Post
Daytime Signal Fade (Independent of Multipath)

Gradual bending allows radio signals to somewhat follow the earth’s curvature for some distance beyond normal line-of-sight. This gradual bending is somewhat independent of phenomenon like ‘tropo scatter’. As you know, long distance TV signals can fade (reduce in strength) in daylight hours. This can be due to smaller temperature gradients that result when the sun uniformly heats the air in the lower atmosphere during much of daytime hours. Smaller temperature gradients result in less bending of the signals back towards the surface, thus the daytime fade.

Note: Temperature is not the end cause of the bending of RF signals. Temperature is a measure of one particular driving factor (thermal energy) that can decrease atmospheric density, thus affecting the density of everything contained in the atmosphere (water vapor, etc).
Attached Images
File Type: jpg DagwoodTVFp1WROC125.JPG (136.6 KB, 200 views)
File Type: jpg DagwoodTVFp1WUHF120.JPG (135.7 KB, 198 views)
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Last edited by rabbit73; 17-Sep-2017 at 2:17 AM.
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Old 17-Sep-2017, 1:28 AM   #13
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Are there any trees in the signal path from Rochester?

Does the problem get worse when it rains?
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Old 17-Sep-2017, 2:07 AM   #14
Dagwood
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Quote:
Originally Posted by rabbit73 View Post
Thanks for checking the voltage to the preamp. If you have a problem again, check to see if the LED on the power inserter is still ON. as it should be, or OFF.
Will do.

Quote:
Thanks for the tvfool signal report.
http://www.tvfool.com/?option=com_wr...e6a4c5db6f4ec6
That description exactly matches your signal report. NBC, ABC, and PBS are your strongest signals, and CBS is listed just a little weaker than PBS. Fox is a lot weaker than CBS.

CBS sends 992 kW out of 1000 kW ERP in your direction. If you click on the CBS callsign in your report, this is what you will see:
http://www.tvfool.com/?option=com_wr...dALLTV%26n%3d4

Fox is much weaker because it has a very directional transmitting antenna that sends only 11 kW out of 320 kW ERP.
http://www.tvfool.com/?option=com_wr...dALLTV%26n%3d5
What you assume is correct; the seasonal change does make a difference. In the warmer weather, the Fox signal is not able to bend down to your location by refraction because the density of the air changes in warm weather.
I hadn't seen those pages, interesting -- I assume my house is way over on the right behind that big hill, heh.

I had no idea what all those numbers meant.

Quote:
Forum member tripelo says it much better than I can:
Also interesting. When I hung around with my high school buddy in the mid-late '60s (he was a CB radio bug) he was always talking about "when the skip comes down" at night, and the signal would travel much farther. Sounds similar. And I know AM radio signals can travel tremendous distances at night, all related to what Tripelo is describing -- I'm assuming.

Quote:
Originally Posted by rabbit73 View Post
Are there any trees in the signal path from Rochester?

Does the problem get worse when it rains?
My house is surrounded by thousands of acres of mature hardwoods, and there are tens of thousands of trees between me and the transmitters, although I'm guessing the hill between us, which is probably 500' higher in elevation than my house is, and 3-ish miles to the north, is more of a factor.

Yes, rain tends to make an edgy signal go out. But, and I bet there's a scientific reason for this, when I was on analog the signal came in better when it was raining.

=======================================================

EDIT: I see you added that image after I started this post. Yes, it all makes sense. This is the first time I've ever seen any hard science for all this. Before, all I ever heard was opinions and guesses from people who didn't necessarily know any more about it than I did.

Thanks! Gotta love the internet!

Last edited by Dagwood; 17-Sep-2017 at 2:12 AM.
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Old 17-Sep-2017, 2:31 AM   #15
rabbit73
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Quote:
My house is surrounded by thousands of acres of mature hardwoods, and there are tens of thousands of trees between me and the transmitters
Trees block TV signals.
http://www.hdtvprimer.com/antennas/siting.html
scroll down to Trees and UHF
Quote:
Yes, rain tends to make an edgy signal go out. But, and I bet there's a scientific reason for this, when I was on analog the signal came in better when it was raining.
Wet trees block TV signals even worse than dry trees.

With analog TV, the signals just got a little more snowy as they got weaker.

With digital TV, they suddenly drop out at a certain point as they get weaker. This point is called the "Digital Cliff."



The sudden dropout is caused by the FEC (Forward Error Correction system). The FEC is designed to correct the digital signal errors to maintain a good quality picture. As the digital signal gets weaker, there are more and more digital errors. The FEC has a limit to how many errors it can correct. Once that limit is exceeded, the FEC gives up, and the signal drops out.
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Last edited by rabbit73; 17-Sep-2017 at 2:38 AM.
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Old 19-Sep-2017, 1:35 AM   #16
Dagwood
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Quote:
Originally Posted by rabbit73 View Post
Trees block TV signals.
http://www.hdtvprimer.com/antennas/siting.html
scroll down to Trees and UHF
Wet trees block TV signals even worse than dry trees.

With analog TV, the signals just got a little more snowy as they got weaker.

With digital TV, they suddenly drop out at a certain point as they get weaker. This point is called the "Digital Cliff."



The sudden dropout is caused by the FEC (Forward Error Correction system). The FEC is designed to correct the digital signal errors to maintain a good quality picture. As the digital signal gets weaker, there are more and more digital errors. The FEC has a limit to how many errors it can correct. Once that limit is exceeded, the FEC gives up, and the signal drops out.
Yes, I found out the different ways the signals act in 2008 when some of the local channels started with digital. And I learned that antenna aiming is more important with digital.

Aside from that (and the problem of everything going dead for hours, twice in the past year) digital has been a huge plus for me. Instead of 3-4 channels I get 12-14.
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