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post #11311 of 11338 Old 10-15-2014, 08:05 PM
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chimney mount straps

Google "chimney mount straps", here is one, instructions also come up.

http://www.solidsignal.com/pview.asp...l-straps-(2212)

You also will need a mast.

SHF
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post #11312 of 11338 Old 10-15-2014, 08:55 PM
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I ordered the chimney straps and a 5 foot mast. I think I got everything that I needed this point except the cable. I really appreciate all the advice I've gotten here thanks to you all. It's nice to have all the parts and assessories that you need when you start a project like this going into it blind.
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post #11313 of 11338 Old 10-15-2014, 09:42 PM
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Quote:
Originally Posted by RayGuy View Post
for one last gasp in the Bay Area. Virtual channel 1.2. Replaces the "Family Channel" which is nowhere to be found. They come and they go, rinse, repeat ....
Thanks for the update, just checked and it looks like it is there. Wonder how long it'll take the in-band EPG information to get updated? They just list "Retro TV" for all the time slots now. I guess I need to update my channel listings as well. Also seems that the old RetroTV (virtual 42.4 - rf14) is off the air.

At least it seems like Schedules Direct has the proper listings for 1.2. Only downside is that KAXT really cuts the bit rate on their channels to pack 12 into one channel.

I also see Escape on 14.4 (rf51), as well as Grit on 66.4 (rf34) have not seen those before, just showed up as I was scanning for new channels. I do see that they show up on Larry's DTV list, so I must have missed them, as well as KEXT (27.1) out of the south bay.

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post #11314 of 11338 Old 10-15-2014, 10:01 PM
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RTV on 1.2 Listings on Tribune Media Services already

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Originally Posted by RayGuy View Post
for one last gasp in the Bay Area. Virtual channel 1.2. Replaces the "Family Channel" which is nowhere to be found. They come and they go, rinse, repeat ....
Checking Zap2It 1.2 already has the correct listings for RTV. So SD and the rest of TMS has the correct listings and I need not (And would not have) done anything.

Checking TitanTV, it still has "MyFamily". Usually TitanTV is the first.

I only looked at "The Naked City' on 1.2 for a few seconds but I could tell that it was worse than KTNC.

SHF
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post #11315 of 11338 Old 10-15-2014, 11:10 PM
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Quote:
Originally Posted by SFischer1 View Post

Checking Zap2It 1.2 already has the correct listings for RTV. So SD and the rest of TMS has the correct listings and I need not (And would not have) done anything.

Checking TitanTV, it still has "MyFamily". Usually TitanTV is the first.

I only looked at "The Naked City' on 1.2 for a few seconds but I could tell that it was worse than KTNC.

SHF
Split 12 ways, it looks damn good!
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post #11316 of 11338 Old 10-16-2014, 01:53 AM
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Howlinrock...

Make sure that you get RG-6 coax with F-connectors for connecting the antenna to your TV, not the smaller sized RG-59 coax. You'll have a lot of loss with the smaller coax.

The antenna you purchased should give you really good signals from all of the Sutro and Mt. San Bruno stations and probably the ones from the South Bay, too. The Novato and Santa Rosa stations might be strong enough to come in off the side and back of the antenna, but no guarantees there. Good luck with your new installation. Let us know what you get once you get it up and working.

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My complete SF Bay Area DTV Station Lists: http://www.choisser.com/sfonair.html
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post #11317 of 11338 Old 10-16-2014, 07:58 AM
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Quote:
Originally Posted by Larry Kenney View Post
Howlinrock...

Make sure that you get RG-6 coax with F-connectors for connecting the antenna to your TV, not the smaller sized RG-59 coax. You'll have a lot of loss with the smaller coax.

The antenna you purchased should give you really good signals from all of the Sutro and Mt. San Bruno stations and probably the ones from the South Bay, too. The Novato and Santa Rosa stations might be strong enough to come in off the side and back of the antenna, but no guarantees there. Good luck with your new installation. Let us know what you get once you get it up and working.

Larry

I will get RG-6 Coax with the f connectors. Thanks Larry for the advice. I'm looking forward to this project/adventure and it's outcome. I will post my findings as I progress ...


John
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post #11318 of 11338 Old 10-16-2014, 08:55 AM
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Quote:
Originally Posted by howlinrock View Post
I will get RG-6 Coax with the f connectors. Thanks Larry for the advice. I'm looking forward to this project/adventure and it's outcome. I will post my findings as I progress ...


John
Before you start, check for any over heads wires that you could hit with the antenna in your hand stretched out. That is the first thing an antenna installer would look for upon arriving.

I suggest that you have a friend help and plan carefully how you are going to walk on the roof and get the antenna to the install location. It is starting to rain so do not make any holes in the roof.

A third person on the ground with a cellphone would be a good idea

Grounding the antenna is required in other locations but even in your location the coax protection may be an consideration in the route down of the cable.


If you have a camera, how about posting a before picture so the experts can comment if necessary.

SHF
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post #11319 of 11338 Old 10-16-2014, 10:41 AM
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Quote:
Originally Posted by SFischer1 View Post
Before you start, check for any over heads wires that you could hit with the antenna in your hand stretched out. That is the first thing an antenna installer would look for upon arriving.

I suggest that you have a friend help and plan carefully how you are going to walk on the roof and get the antenna to the install location. It is starting to rain so do not make any holes in the roof.

A third person on the ground with a cellphone would be a good idea

Grounding the antenna is required in other locations but even in your location the coax protection may be an consideration in the route down of the cable.


If you have a camera, how about posting a before picture so the experts can comment if necessary.

SHF

There are no over head wires around my house or in the area. Probably going to wait until we are rain clear. Going to attached to chimney not the roof. Will work a plan with 2 others using phone. Also there is still an old antenna in my attic that needs to go as I don't want to install another there. I will post pictures of the antenna install and I move forward with weather and install help's availability. Thanks for the suggestions and advice
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post #11320 of 11338 Old 10-16-2014, 11:18 AM
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KAXT TSReader Output Attached 10/16/2014

Quote:
Originally Posted by RayGuy View Post
Split 12 ways, it looks damn good!
Route66 capture overnight scheduled.

Looking at another program on RTV it looked great.


RTV appears to be top dog from the 30 second capture I did. Video PID 145 (0x0091)

I have attached the TSReader output for KAXT.

SHF


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post #11321 of 11338 Old 10-16-2014, 05:55 PM
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Another program change: KTLN 68.4 has been changed from Cool TV to Jewelry TV. Cool TV remains on 68.2.

Larry

My complete SF Bay Area DTV Station Lists: http://www.choisser.com/sfonair.html
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Check out photos and info on my antennas: http://www. larrykenney.com/tvantennas.html

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post #11322 of 11338 Old 10-17-2014, 11:45 PM
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I've been watching for some better than usual conditions lately with all of the warmer weather and off shore winds, but I haven't seen anything but continuously normal conditions for weeks. Normally at this time of the year I see much stronger signals from distant stations, but not this year. Have any of you seen any extremely good or bad reception lately?

Larry

My complete SF Bay Area DTV Station Lists: http://www.choisser.com/sfonair.html
Lots of Broadcasting links and information: http://www.choisser.com/broadcast.html

Check out photos and info on my antennas: http://www. larrykenney.com/tvantennas.html

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post #11323 of 11338 Old 10-18-2014, 08:10 AM
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Quote:
Originally Posted by Larry Kenney View Post
I've been watching for some better than usual conditions lately with all of the warmer weather and off shore winds, but I haven't seen anything but continuously normal conditions for weeks. Normally at this time of the year I see much stronger signals from distant stations, but not this year. Have any of you seen any extremely good or bad reception lately?

Larry

I've seen little in the way of extreme conditions the last few weeks. Signals always vary at least some here during the day though. A week ago Thursday I lost a couple of recordings on different channels in the evening and had to watch the 2nd half of a program on Hulu. Other than that there have been no issues. I was even able to watch the 49ers on KPIX last Monday. As an ESPN game it was not broadcast OTA except in the Bay Area. KPIX rarely gets above SNR 20 dB but it was in for almost the entire game.

Chuck
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post #11324 of 11338 Old 10-18-2014, 09:04 AM
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I've seen little in the way of extreme conditions the last few weeks. Signals always vary at least some here during the day though. A week ago Thursday I lost a couple of recordings on different channels in the evening and had to watch the 2nd half of a program on Hulu. Other than that there have been no issues. I was even able to watch the 49ers on KPIX last Monday. As an ESPN game it was not broadcast OTA except in the Bay Area. KPIX rarely gets above SNR 20 dB but it was in for almost the entire game.

Chuck
great explanation of inner works of dtv on your page chuck, question though, I get my dtv signals from esb (empirestatebuilding) which is 6 miles from me, my setup includes a 91xg at 30' hdp269 12db preamp, I don't get any overload being this close, I have this setup to receive signals from other locations. here is my question, would I be able to use another preamp with slightly more gain (rca 22 dbs or winegard ln 200) before I get signal overload, in other words how much can i get away before I'm cooked. tv fool http://www.tvfool.com/?option=com_wr...d243fa50381945

thanks for replying.
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post #11325 of 11338 Old 10-18-2014, 10:01 AM
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Quote:
Originally Posted by uhfyagi View Post
great explanation of inner works of dtv on your page chuck, question though, I get my dtv signals from esb (empirestatebuilding) which is 6 miles from me, my setup includes a 91xg at 30' hdp269 12db preamp, I don't get any overload being this close, I have this setup to receive signals from other locations. here is my question, would I be able to use another preamp with slightly more gain (rca 22 dbs or winegard ln 200) before I get signal overload, in other words how much can i get away before I'm cooked. tv fool http://www.tvfool.com/?option=com_wr...d243fa50381945

thanks for replying.

Your question leads me to believe I have failed to explain the role of preamp gain. Unless you have a long download from your antenna, say >100', it is highly unlikely that more preamp gain will get you anything at all, except maybe overload.

Since I have no idea what your actual signal levels are I cannot say what gain will cause overload problems. I think it was smart choice to use an HDP269.

If you supply me with more details of your setup I can plug them into my system noise figure spreadsheet and tell you what improvement if any you might get from a different preamp.

1) Length and type of coax?
2) Splitter?
3) Distribution amp? Model?

Basically I need to know the total loss between the preamp output and the TV input or distribution amp if you're using one of those.

Chuck
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post #11326 of 11338 Old 10-18-2014, 10:09 AM
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Originally Posted by Calaveras View Post
Your question leads me to believe I have failed to explain the role of preamp gain. Unless you have a long download from your antenna, say >100', it is highly unlikely that more preamp gain will get you anything at all, except maybe overload.

Since I have no idea what your actual signal levels are I cannot say what gain will cause overload problems. I think it was smart choice to use an HDP269.

If you supply me with more details of your setup I can plug them into my system noise figure spreadsheet and tell you what improvement if any you might get from a different preamp.

1) Length and type of coax?
2) Splitter?
3) Distribution amp? Model?

Basically I need to know the total loss between the preamp output and the TV input or distribution amp if you're using one of those.

Chuck
Sorry bout that chief,

50 ft of rg6
No splitter
No da

Txs
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post #11327 of 11338 Old 10-18-2014, 10:45 AM
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chuck I can get receive a channel at night that TV fool shows minus 10 db so I agree with you that TV fool is erroneous. I forgot too mention that all the channels I receive are not in line of sight, my antenna is pointed at high rise 60 ft from my location, I have no Los to esb or other TV transmitters. pre digital transition 2009, all channels were received with heavy multipath, ghosting.

Last edited by uhfyagi; 10-18-2014 at 10:54 AM.
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post #11328 of 11338 Old 10-18-2014, 11:13 AM
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Quote:
Originally Posted by uhfyagi View Post
Sorry bout that chief,

50 ft of rg6
No splitter
No da

Txs
I assumed the following:

TV tuner Noise figure = 6.0 dB
50' of RG-6 at 700 MHz = 2.5 dB loss
Misc loss = 0.5 dB
HDP269 average gain on UHF = 11 dB (as measured by me) and Noise Figure = 3.0 dB

Your System Noise Figure is 4.1 dB. If everything else stays the same and you increase the gain to 22 dB, the System Noise Figure will be 3.1 dB. That would increase the Signal-to-Noise of weak signals by 1 dB assuming the increase in gain caused no overload problems.

Once you have a decent antenna and a preamp it is very hard to make much improvement in reception. 1 dB isn't much. 3 dB is something but very hard to get.

If you purchased a Tin Lee MA-16U-77 preamp for your 91XG and it had a 1.5 dB Noise Figure as I have measured here, your System Noise Figure would be 2.0 dB so you'd get 2.1 dB SNR increase. That might be noticeable on a few marginal stations.

If you stacked two 91XGs you'd get about 2 db more. If you replaced the baluns with low loss coax baluns and used used a coax 1/4 wave combiner like I made, you might get another 1.5 dB.

So with a better preamp, two antennas and better matching, you could approach a 6 dB SNR improvement which would be significant. Those are things a motivated person can do. Beyond that you're talking about >10' dish antennas.

Chuck
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post #11329 of 11338 Old 10-18-2014, 11:28 AM
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Quote:
Originally Posted by uhfyagi View Post
chuck I can get receive a channel at night that TV fool shows minus 10 db so I agree with you that TV fool is erroneous. I forgot too mention that all the channels I receive are not in line of sight, my antenna is pointed at high rise 60 ft from my location, I have no Los to esb or other TV transmitters. pre digital transition 2009, all channels were received with heavy multipath, ghosting.

What is ESB?

It's very hard to do much about multipath once you have a decent antenna. An antenna with a tight pattern and few lobes can help greatly for multipath coming from directions other than the transmitter. But multipath can come from the same direction as the transmitter. I discovered I have both issues when attempts to increase the F/B ratio didn't improve my SNRs. An antenna in a cage can do a lot for side and back issues but nothing for same direction issues. Mounting options are limited for those.

It's extremely common for people to report receiving some stations at night and not in the daytime, especially the afternoon. This is caused by temperature inversions that commonly form around sundown, and last into the morning until solar heating breaks them up. It doesn't take much of an inversion to extend the range of a station a bit.

Chuck
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post #11330 of 11338 Old 10-18-2014, 11:56 AM
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Quote:
Originally Posted by uhfyagi View Post
I get my dtv signals from esb (empirestatebuilding) which is 6 miles from me, http://www.tvfool.com/?option=com_wr...d243fa50381945
An easy 100+ OTA channel location...... Not sure how to expand the tvfool chart to show more.
Shows both Analog 6 .... (Used for FM)..... and Digital 6 ...?

How do those work out ?
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post #11331 of 11338 Old 10-18-2014, 01:07 PM
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An easy 100+ OTA channel location...... Not sure how to expand the tvfool chart to show more.
Shows both Analog 6 .... (Used for FM)..... and Digital 6 ...?

How do those work out ?
I cant receive those 2 channels, but the programming is in chinese they repeat on another 6 stations with the same call letters. 100 channels easily? my elevation is 80 feet, NYC is close to sea level. chuck your setup is awesome.
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post #11332 of 11338 Old 10-18-2014, 09:24 PM
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Quote:
Originally Posted by Calaveras View Post
What is ESB?

It's very hard to do much about multipath once you have a decent antenna. An antenna with a tight pattern and few lobes can help greatly for multipath coming from directions other than the transmitter. But multipath can come from the same direction as the transmitter. I discovered I have both issues when attempts to increase the F/B ratio didn't improve my SNRs. An antenna in a cage can do a lot for side and back issues but nothing for same direction issues. Mounting options are limited for those.

It's extremely common for people to report receiving some stations at night and not in the daytime, especially the afternoon. This is caused by temperature inversions that commonly form around sundown, and last into the morning until solar heating breaks them up. It doesn't take much of an inversion to extend the range of a station a bit.

Chuck
He mentioned in an earlier post that ESB is the Empire State Building, he's in New York City.... A bit out of our purview....

Bobby 

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post #11333 of 11338 Old 10-19-2014, 12:33 AM
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Quote:
Originally Posted by Larry Kenney View Post
I've been watching for some better than usual conditions lately with all of the warmer weather and off shore winds, but I haven't seen anything but continuously normal conditions for weeks. Normally at this time of the year I see much stronger signals from distant stations, but not this year. Have any of you seen any extremely good or bad reception lately?

Larry
Somewhat enhanced signals from all the north bay stations tonight (Saturday) around 10pm. Stable with no swinging dropouts for extended periods.
22, 50, & 68 ..... all at +50% with a fixed garage attic antenna.... (pointed toward KEMO)

KSBW is gone now.
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post #11334 of 11338 Old 10-19-2014, 05:38 AM
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Quote:
Shows both Analog 6 .... (Used for FM)..... and Digital 6 ...?

How do those work out ?
TVFool displays issued construction permits without distinguishing whether or not they are on the air. Only the analog 6 "Franken FM" is on the air. The digital 6 is for the un-built digital system that has been applied for and approved. The analog signal will have to go off the air late next summer when all analog must cease.
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post #11335 of 11338 Old 10-19-2014, 08:23 AM
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[HDTV-in-SFbay] Interference when DTV sets off

https://groups.yahoo.com/neo/groups/...messages/30401


When I was a kid, I quickly discovered that if you turned on two AM radios and put them in close proximity, one could interfere with the other if tuned it just right.

Turns out DTV's can do that too ... except in this case while one TV is actually off.

So, if you have 2 TV's connected to the same antenna, and one is off, this is a possibility. Fascinating.

http://www.tvtechnology.com/article/accidental-discovery-through-testing/272723

BD

------------------------------------
Posted by: Duke And Rat
------------------------------------
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post #11336 of 11338 Old 10-19-2014, 10:26 AM
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My first thought was that the solution is to add an isolator to the input of each TV but then I remembered that there is supposed to be port-to-port isolation in a splitter. I measured the isolation of two different 2-way splitters at UHF with the input terminated. See attached images. Seems like >20 db ought to be enough but then I removed the termination and the isolation dropped to <10 dB which is not much. Looks like the isolation is poor if the impedance matching is poor.

I wish he had mentioned in the article what he considers to be "strong" VHF signals.

The only way to troubleshoot this problem would be to turn off other TVs when viewing a "problem" UHF station to see if the station disappeared. If it did then you need to add an A/B switch with port B terminated and switch the offending TV out to view the weak UHF station on another TV.

Hopefully this falls in the category of the strong FM station harmonic problem on high VHF, possible but seldom encountered.

Chuck
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post #11337 of 11338 Old Yesterday, 11:26 AM
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distant digital television signals are rare to non-existant for me, i've received KRCB 22 once and that's it.

but FM radio signals were showing up from new places yesterday, the only one i liked enough to ID was 93.7 "Kiss Country", KSKS. It looks like their tower is in the foothills east of Fresno.
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post #11338 of 11338 Old Yesterday, 12:24 PM
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Quote:
Originally Posted by CTEL08 View Post
distant digital television signals are rare to non-existant for me, i've received KRCB 22 once and that's it.

Reception of distant DTV stations is just like real estate, it's location, location, location. Blocking terrain is everything. It's entirely possible to be in a location where no ducting is ever good enough to receive a distant station. OTOH, there are locations like Josh in Newman where the slightest ducting brings in stations from all over.

Any location with unobstructed horizons in the direction of distant stations is likely to have some interesting reception possibilities.

Chuck
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Reply Local HDTV Info and Reception

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