Not MC, TV antenna issues.

[Flyinfool]

OK it always seems that there is some one that will know something or at least have some good ideas.

 

Here is my situation. The cable price just took a dramatic price jump and has exceeded my wallet tolerance.

So I got an omnidirectional antenna since I am only about 15 miles from the transmitters.

Overall the antenna works great.

 

The problem is, the transmitters are all almost due north of me. Directly across the street to the north is a 5 story high brick apartment building. The picture quality is still flawless. Now the fun part. I live very close to an international airport with a lot of airliner traffic. The airliners go by about 2 city blocks to the south of me and are at less than 1000 feet AGL on final for the favorite runway. The planes go by about every 2 - 3 minutes. With each plane that goes by It wipes out my TV picture and sound due to loss of signal. I think that what is happening is that the broadcast signal is bouncing off the side of the airplanes and hitting my antenna out of phase with the broadcast signal so neither one can get through.

 

I bought and tried a directional antenna and that helped a little. I get the signal interruption for a short time and then it clears when the plane is exactly off the back of the antenna and then goes out again as the plane continues on by.

 

Would it help to put up a wall of aluminum foil on the back side of the antenna to try to block the reflected signal? DO I need to ground it?

Would I be better off spending the big bucks on a bigger more directional antenna?

 

Any other ideas form those that understand how radio waves work????

[utadventure]

The issue may be the antenna. Omni means all directions.... you may need an antenna that only receives signals from the direction it's pointed. This may reduce the channels you get but reduce or eliminate the issues.

[cimmer]

yes, the omnidirectional isn't the best idea here. You want a directional antenna and one designed for HDTV signal. Also where do you have the antenna mounted at presently? I have a digital antenna as a backup to the cable and have it mounted in my attic. It receives signals from the towers that about 35 miles north of me plus some other ones around the area. Check around and you can find a good one that will work for you.

Check out this link for some ideas. https://www.tomsguide.com/us/best-tv-antennas,review-2354.html

 

 

Rick F.

[cowpuc]

I know less about antenna's then I do even motorcycles but cant help but wonder if a directional antenna mounted on top of an old school tower with an old school rotor assembly who's movement is controlled by one of those old school rotor control boxes from inside the house would not be the answer Fool... Maybe the ability to "swing the beams" to "tune out" the interference would do it...

 

,,, could dress the tower up to look like an ICWWDS (Inter Continental White Wash Delivery System)

[Marcarl]

I think you are on to him Puc, he's trying to pull the wool over our heads with this idea of his and when he gets it tuned just right and kerplunks all that white stuff where he so desires he can blame it all on this thread and the ideas posted here. Maybe a mod should delete this thread just in case.

[rickardracing]

Why would you want to live that close to approaching air traffic? With all the obstacles around, maybe time to sell or just loosen up the purse strings and pay the higher rate.

[campfire12]

Jeff. I have 2 antenna on my roof. There directional and are pointed 2 different ways so as to get 2 different paths to receive signals. There just tied together at the antenns with a splitter and coated with flex-seal. went from 7 or 8 stations to about 35 free stations. cut the cable cord this summer and its great. Good luck!

[videoarizona]

Jeff, as stated above...you do need a "high" gain directional antenna. Not needed... is an antenna designed to pick up @cowpuc speaking lovingly to his Tippy over 100 miles away! Just a good design gain antenna. The better ones will reject false signals...though, to be honest, that really is the job of the TV tuner.

 

Grounding won't help...or least least it shouldn't as that's not how an antenna works. But stranger things I've seen in antenna design working with AM stations years back.

 

Go to a good antenna place...not Best Buy type places as they still think you need an "HD" antenna to get TV nowadays. Tell them your problem.

 

A good old yagi type..or even the good Channel Master series from the 60's would probably work! When I moved to Green Valley, A old Radio Shack dude told me I had to have one of those new whizbang HD antennas to get the signal from Tucson...over 40 miles away. (I went there to get the compass direction for the mountain that had the antennas - He was wrong all all counts and I told him so. He tried to bluff his way back into my good graces....nope..you don't fart around with an old phart who loved radio and TV stuff and worked it as well....). I ended up finding an old Channel Master UHF/VHF design that was being thrown out and bought it for free! Put it on an 8 foot pole on the back side roof of the house and get all the TV stations crystal clear in HD.

 

https://www.channelmaster.com/Digital_HDTV_Outdoor_TV_Antenna_p/cm-3016.htm

 

https://en.m.wikipedia.org/wiki/Directional_antenna

[cowpuc]

Jeff, as stated above...you do need a "high" gain directional antenna. Not needed... is an antenna designed to pick up cowpuc speaking lovingly to his Tippy over 100 miles away! Just a good design gain antenna. The better ones will reject false signals...though, to be honest, that really is the job of the TV tuner.

 

Grounding won't help...or least least it shouldn't as that's not how an antenna works. But stranger things I've seen in antenna design working with AM stations years back.

 

Go to a good antenna place...not Best Buy type places as they still think you need an "HD" antenna to get TV nowadays. Tell them your problem.

 

A good old yagi type..or even the good Channel Master series from the 60's would probably work! When I moved to Green Valley, A old Radio Shack dude told me I had to have one of those new whizbang HD antennas to get the signal from Tucson...over 40 miles away. (I went there to get the compass direction for the mountain that had the antennas - He was wrong all all counts and I told him so. He tried to bluff his way back into my good graces....nope..you don't fart around with an old phart who loved radio and TV stuff and worked it as well....). I ended up finding an old Channel Master UHF/VHF design that was being thrown out and bought it for free! Put it on an 8 foot pole on the back side roof of the house and get all the TV stations crystal clear in HD.

 

https://www.channelmaster.com/Digital_HDTV_Outdoor_TV_Antenna_p/cm-3016.htm

 

https://en.m.wikipedia.org/wiki/Directional_antenna

 

Tip, Tweeks, Maggie, Trooper and Puc are hiding behind a great big Lake Michigan sand dune so unlike Fool's ability to use artillary "fire for effect" techniques in his ongoing attempt to bury us in Wisconsin White Wash,,,, spying on us with radio signal transmissions would not work cause of no line of sight,,,, :rasberry::moon: neighbor to the west!!!

[Flyinfool]

As I stated in my first post, I started with a Omni and then switched to a directional antenna. The directional helped but did not fix the issue. I do not think that it is a TV tuner issue. If you have 2 or more valid signals all originating from the same antenna, there is no way for the TV to know which is the correct one.

 

At the moment I have the antenna in the attic, strength of signal is not the issue, I get 40 channels. I just need to find a way to block the multi-path signals. I hate to go and spend a couple hundred bucks on a big very directional antenna and have it not work. All the TV antennas are in the same direction from me so I do not need a rotator. I do not know if mounting it 0n the roof would buy me anything. I was wondering if it would help to build a grounded wall of aluminum foil or screen behind the antenna to try to block or at least attenuate the unwanted signals.

 

All TV antennas including all of them made before HD was invented will work equally well for receiving the signal. The term HD compatible antenna is nothing but marketing. The antenna does not know if the signal is digital or analog, it is no different than if the transmission is in German or English, it is just an RF signal and that is all that the antenna cares about.

@cowpuc

You sand dunes will not help against ELF radio signals, ELF has no problem penetrating ground. Even a mountain will not help. :stirthepot:

[snyper316]

Heck I live in Joplin and have to run an amplifier just to get all the joplin stations, since they went digital I have done nothing but fight to get a signal... I have airplanes that come in and out of Joplin regional airport. But not nearly as much as you fool. When I lived out in the country everytime it would rain I was losing signal... What a great Idea to go digital I used to be able to get Springfield, Arkansas, Oklahoma, Kansas, and Joplin stations till the big upgrade...

[cowpuc]

cowpuc

You sand dunes will not help against ELF radio signals, ELF has no problem penetrating ground. Even a mountain will not help. :stirthepot:

 

Oh yea,,, wait till those ELF's of yourn hear Tippy bawling you and your infamous White Washer out,,,, I betcha those little ELFers will turn tail and run,, never to be heard of again on this side of the pond brother!!!

 

:rasberry::moon::rasberry::moon:

 

Go to 10 seconds in:hihi::

[djh3]

Fool, can you go ask neighbors? Maybe see if they experience same thing or maybe have a remedy for it. I use to live on the flight path of the Air Base I was stationed at. I had about the biggest antenna I could get, signal amp and I was lucky to get the PBS from OKC, ABC from Lawton and maybe a CBS from there, occasionally with adjustment a couple stations fuzzy from Amarillo. Planes did not seem to bother me there, other than you just couldnt hear anything for about 2 min while they turned overhead.

[videoarizona]

 

Jeff,

Yes there is. The tuners of the Flintstone days did it by picking the strongest or earliest and filtering out the rest. The best of the analog tuners would pretty much eliminate ghosts.

 

The NTSC TV system we have today is the worst choice of the 2 major competing signal formats. Much like the FCC chose NTSC as our TV format back in the days of wooden airplanes....so...they have chosen the wrong format twice! NTSC (Never The Same Color) was a ***** to make work...but good old US engineers got it worked out.

 

Same holds true for the newer signal format, 8VSB. 8VSB was the worst at multipath rejection, ghosting (ad nauseum) proven in 2008 in every major metro area where it was tested. It's only virtue is it's ability to reach out and go long....

 

TV Tuners of today are now on their 8th or 9th generation of tuners(or more) and are just now beginning to work as well as the other competing signal format ()COFDM) would have worked on it's 1st generation.

 

The ATSC signal format is really not good for the USA as the majority of it's population live in cities where multipath is the worst known problem and the major reason why cable TV got so much market penetration in cities.

 

++++++++++++++++++

1:

 

[/color]"While the ATSC system has been criticized as being complicated and expensive to implement and use,^[13] both broadcasting and receiving equipment are now comparable in cost with that of DVB.

The ATSC signal is more susceptible to changes in radio propagation conditions than DVB-T and ISDB-T. It also lacks true hierarchical modulation, which would allow the SDTV part of an HDTV signal (or the audio portion of a television program) to be received uninterrupted even in fringe areas where signal strength is low. For this reason, an additional modulation mode, enhanced-VSB (E-VSB) has been introduced, allowing for a similar benefit.

In spite of ATSC's fixed transmission mode, it is still a robust signal under various conditions. 8VSB was chosen over COFDM in part because many areas are rural and have a much lower population density, thereby requiring larger transmitters and resulting in large fringe areas. In these areas, 8VSB was shown to perform better than other systems.

COFDM is used in both DVB-T and ISDB-T, and for 1seg, as well as DVB-H and HD Radio in the United States. In metropolitan areas, where population density is highest, COFDM is said to be better at handling multipath propagation. While ATSC is also incapable of true single-frequency network (SFN) operation, the distributed transmission mode, using multiple synchronized on-channel transmitters, has been shown to improve reception under similar conditions. Thus, it may not require more spectrum allocation than DVB-T using SFNs. A comparison study found that ISDB-T and DVB-T performed similarly, and that both were outperformed by DVB-T2.^[14]"

 

 

^{++++++++++++++++++++++++++++}

^2:

 

Disputes over ATSC's use[edit]

 

For some period of time, there had been a continuing lobby for changing the modulation for ATSC to COFDM, the way DVB-T is transmitted in Europe, and ISDB-T in Japan. However, the FCC has always held that 8VSB is the better modulation for use in U.S. digital television broadcasting. In a 1999 report, the Commission found that 8VSB has better threshold or carrier-to-noise (C/N) performance, has a higher data rate capability, requires less transmitter power for equivalent coverage, and is more robust to impulse and phase noise.^[2] As a result, it denied in 2000 a petition for rulemaking from Sinclair Broadcast Group requesting that broadcasters be allowed to choose between 8VSB or COFDM as is most appropriate for their area of coverage.^[3] The FCC report also acknowledged that COFDM would "generally be expected to perform better in situations where there is dynamic multipath," such as mobile operation or in the presence of trees that are moving in high winds. However, with the introduction of 5th Generation demodulators in 2005 and subsequent improvements in generations 6 and 7, the equalization span is now about −60 to +75 microseconds (a 135 microsecond spread) and has virtually eliminated multipath, both static and dynamic, in 8VSB reception. In comparison, the equalization span in COFDM is −100 to +100 microseconds (200 microsecond spread), but the application of this much guard band space for COFDM substantially reduces its useful payload. In fact, much of Europe has adopted 1280×720p as its HD standard for DVB-T1 because of its reduced payload capacity^{[citation needed]}. The introduction of DVB-T2 is meant to increase the ability of terrestrial transmissions to carry 1920×1080p content. 1920×1080i has always been part of the 8VSB scheme from its inception, and its improved demodulators have had no effect on its innate payload capacity^{[citation needed]}.

Because of continued adoption of the 8VSB-based ATSC standard in the U.S., and a large growing ATSC receiver population, a switch to COFDM is now essentially impossible. Most analog terrestrial transmissions in the US were turned off in June 2009, and 8VSB tuners are common to all new TVs, further complicating a future transition to COFDM.

8VSB vs COFDM[edit]

 

The previously cited FCC Report also found that COFDM has better performance in dynamic and high level static multipath situations, and offers advantages for single frequency networks and mobile reception. Nonetheless, in 2001, a technical report compiled by the COFDM Technical Group concluded that COFDM did not offer any significant advantages over 8VSB. The report recommended in conclusion that receivers be linked to outdoor antennas raised to roughly 30 feet (9 m) in height. Neither 8VSB nor COFDM performed acceptably in most indoor test installations.^[4]

However, there were questions^[who?] whether the COFDM receiver selected for these tests − a transmitter monitor [2] lacking normal front end filtering − colored these results. Retests that were performed using the same COFDM receivers with the addition of a front end band pass filter gave much improved results for the DVB-T receiver, but further testing was not pursued.[3]^{[permanent dead link]}

The debate over 8VSB versus COFDM modulation is still ongoing. Proponents of COFDM argue that it resists multipath far better than 8VSB. This is important property of the modulation for receiving HDTV in e.g. moving vehicles that is not possible with 8VSB. Early 8VSB DTV (digital television) receivers often had difficulty receiving a signal in urban environments. Newer 8VSB receivers, however, are better at dealing with multipath, but a moving receiver can still not receive the signal. Moreover, 8VSB modulation requires less power to transmit a signal the same distance. In less populated areas, 8VSB may outperform COFDM because of this. However, in some urban areas, as well as for mobile use, COFDM may offer better reception than 8VSB. Several "enhanced" VSB systems were in development, most notably E-VSB, A-VSB, and MPH. The deficiencies in 8VSB in regards to multipath reception can be dealt with by using additional forward error-correcting codes which decreases the useful bit rate, such as that used by ATSC-M/H for Mobile/Handheld reception. ATSC 3.0, the next major television standard in the United States, will use COFDM.

 

The vast majority of U.S. TV stations use COFDM for their studio to transmitter links and news gathering operations^{[citation needed]}. These are point-to-point communication links and not broadcast transmissions.

 

Bottom Line:

 

The better tuners available today do filter out the multipath interference you are experiencing, Jeff.....but most of the TV's put out today go as cheap as they can with the tuners. Why not, right? With the heavy market penetration of cable tv...you don't need a good tuner to pick up a signal that's a foot away on a cable path. This silly thinking disregards the fact that more people in the USA receive their TV OTA....with a simple antenna. You and I are just 2 of the millions who do.

 

Your TV signal will be disrupted by airplanes and buildings easily due to where you live. (I remember your proximity to the airport). You can try and put a cheap, directional antenna on the roof and see what happens. You can also try and move the antenna from the East side to the West side of the house, or North to South. Any movement should make some difference in the multipath environment you live in. Or you could buy one of those really cheap (under $20) flat antennas and move it around the living room. Maybe even behind the fish tank. By moving the antenna around, you are doing physically what the tuner should be doing electronically.

And yes, with a cheap antenna, putting some aluminum foil behind it as a backing plate may make the signal better or worse. It shouldn't, as the tuner should reject the delayed, latent or ghosting signals...but since they don't as well as they should....anything you do may/may not help. So I'm revising my thinking on foil usage.

 

I keep forgetting, the FCC is made up of lawyers, not true engineers, so they will choose what works best for lining their pockets, not what's best for the country. That's got to be the reason they chose the wrong format AGAIN.....because not one TV engineer on the testing panels agreed with them on their choice of digital formats.

 

Sorry for the long post...but this has pissed me off since 2005. I'm having a little trouble letting it go. I guess I simply don't like stupidity...in any way, shape or form. Ignorance is OK even to be expected among the best and brightest....but seeing test results then denying them are a whole nuther ball game.

 

Speaking of ball game...Go Astros!

 

David...grumbling in the desert....

[Flyinfool]

Thanks David.

I even tried turning the directional antenna that I now have around and pointing it at the water tower that is 1 block to the west of me. While I actually got 12 more channels with the antenna pointed that way. The airplanes cause the TV to go blank with the loss of signal message with every plane that went by.

Someone mentioned that I should try turning the antenna so that the elements are vertical as that may also help my issue. Heck it dont cost nuttin to try different spots and orientations.

 

Some one else mentioned that seeing as how close I am to the transmitters, adding an attenuator may knock the multi path down far enough to not be seen while still leaving enough real signal to get the job done.

While it could be a poorly designed tuner in my TV, this does affect all the TVs in the house, and my big TV is a fairly new high end Samsung so I would hope that is OK.

 

Another thought is to spend some cash on a much bigger, more directional antenna. $100 for a big antenna is still only a bit more than one month of cable TV bill.

[cowpuc]

,, call the airport and ask em to change their flight schedules to coincide with your non-viewing/sleeping hours

 

Cut em a deal using your White Washer as leverage = you'll sign a non-run way targeting contract that confirms all flights will now be during your "off" hours...

You may be an awesome engineer brother but your wheelin/dealin negotiating skills need some sharpenin,, IMHO

[Flyinfool]

I talked to a place that does nothing but antennas and they recommended a few things for me to try.

 

One was to move the antenna to the back of the house so that the backside of the antenna is right up against the wall of the attic. They said that in testing the closer the antenna is to a wall the more the wall attenuates the signal. Then they said to cover that wall with aluminum foil or screen and make sure that shield is connected direct to a ground rod and not just the ground of an outlet.

If all that fails then they said I will need to go to a really big, very directional antenna with a selective filter/amplifier. So I will try the free or cheap stuff they recommended first. I guess I trust them since they said to by stuff from them was the last resort.

 

So I now have a direction to follow. We will see what happens this coming weekend when I have some time to work on it.

[videoarizona]

Remember, the really big antenna will make a strong signal. So pick up 2 strong in-line attenuators... and try them too. Overloading the front end of your tuner won't give you a better picture....

 

You will get close, that I'm sure.

[rbig1]

well I have a 13' antenna with a rotor attached. now when the wind trys to blow away the house. the antenna turns in the rotor and changes the settings. Cant seem to get it to stay in place so always having to hunt for signal after wind event. the neighbors masts have all bent. I cut mine down in height to 4 foot. dont bend but still slips dont know if its the pole or rotor-gears slipping now. Still better than paying for what should be free.

[Flyinfool]

Slipping is easy to fix. just put a screw thru the antenna and mast to act as a shear pin, and they will never slip again. You can do the same at the top and bottom of the rotor and the tripod. If it is the gears slipping, then only a new rotor will fix it.

[Sylvester]

How far can these antennas reach? I live maybe thirty miles (as the crow flies) from Charlotte and would like to cut the apron strings. I have a UHF antenna (on a twenty ft. galvanized fence rail) above my wood working shop to get radio signals and it does great, and the shop is around twenty feet lower than the house.

 

[cowpuc]

How far can these antennas reach? I live maybe thirty miles (as the crow flies) from Charlotte and would like to cut the apron strings. I have a UHF antenna (on a twenty ft. galvanized fence rail) above my wood working shop to get radio signals and it does great, and the shop is around twenty feet lower than the house.

 

 

 

,, I was never really good with algebrahick quations ,,,,, = :lightbulb:20 feet? , :crackup:, :rotfl:

 

Ohhhh my gosh Sly,,,, you and I are gonna have sooooo much fun up yonder

[Sylvester]

,, I was never really good with algebrahick quations ,,,,, = :lightbulb:20 feet? , :crackup:, :rotfl:

 

Ohhhh my gosh Sly,,,, you and I are gonna have sooooo much fun up yonder

 

I am looking forward to it my brother.

[videoarizona]

How far can these antennas reach? I live maybe thirty miles (as the crow flies) from Charlotte and would like to cut the apron strings. I have a UHF antenna (on a twenty ft. galvanized fence rail) above my wood working shop to get radio signals and it does great, and the shop is around twenty feet lower than the house.

 

 

 

If you want reach, a good old UHF/VHF antenna can go up to 100miles, they say. I would say, no...maybe 80 miles max if you are above average terrain and don't have mountains in the way. Most of the really good ones will get you 50 to 60 miles.

 

https://www.channelmaster.com/Digital_HDTV_Outdoor_TV_Antenna_p/cm-3016.htm

 

 

Mine is the equivalent to the 60 mile unit. But it's about 25 years old. It sits on an 8 ft pole on the roof of the back patio (about 22ft above average terrain)...so it has to look through the roofline to see the mountain where Tucson's TV transmitters are. They are about 45 miles away....

Edited October 30, 2019 by videoarizona

[videoarizona]

My old, beat up antenna.