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  #16  
Old 01-28-2015, 08:50 PM
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The most powerful DTV stations ARE as powerful as the
most powerful analog ones, at least on high VHF and
UHF.

That's because NTSC stations are rated at peak sync tip power and
DTV ones are average power.
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  #17  
Old 01-28-2015, 10:39 PM
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Originally Posted by NoPegs View Post
Plug your information into www.antennaweb.org and make sure that the channel you're having issues with isn't a "Violet" signal.
I just went to antennaweb.org, logged in, and saw that the channel I am not receiving isn't shown in the list of stations I should be receiving here. That struck me as rather odd; after all, channel 19 is a major TV network affiliate (CBS), and so should have a DTV signal that covers every bit as much area as the analog one did. Because of this (that the station isn't listed as one of the channels normally received in my area), I don't know whether it would be shown with a violet marker on the channel list. The ERP analog transmitter output for this station, as shown on the FCC's listings, is 3.1 kilowatts; the DTV signal's ERP either is not mentioned or I didn't see it in the listing the first time around. I'll have to look at it again; it could very well be that the DTV power level is substantially lower than the analog ERP was.

I do remember reading somewhere that it can be very difficult to receive channel 19's DTV signal in some far-suburban/near-fringe areas without a large, fringe-area antenna. The fact that 19's DTV signal is being transmitted on VHF channel ten isn't helping matters much either. It strikes me as odd, again, that the station was assigned a high-VHF channel for its DTV transmissions, when most TV stations in this area (and nationwide) are now on UHF DTV channels. There is a Canadian television station, almost due north of Cleveland across Lake Erie, on the same channel as channel 19's DTV assignment; this is causing some problems for both stations, in the form of co-channel interference during temperature inversions and other seasonal conditions that cause TV signals to travel hundreds or even thousands (!) of miles beyond their normal service area.

As I mentioned in my last post, channel 19's owner and licensee, Raycom Communications, applied for and was granted permission to increase the station's ERP power level substantially so as to cover the Akron, Ohio area as close to reliably as possible. This power increase is, IMO, a poor solution to the problem (my experience as an amateur radio operator tells me that a more reliable way to increase the range of an RF signal is to raise or improve the antenna system--not to rely on a power increase while using the same antenna system), but apparently the station is doing it this way until such time as they can move their DTV signal to a UHF channel, whenever that may be.



Unfortunately, however, even that power increase is not enough (nowhere near) to remedy the reception problems in areas to the far east and far west of the station's antenna towers in the Cleveland suburb of Parma. The only way, again, that the station is going to even come close to ending these reception problems is to move its signal to a UHF channel. All other TV stations in this area are on UHF DTV assignments, and I can receive them quite well at my apartment using the Zenith amplified DTV indoor antenna. I was experimenting with the antenna earlier today and found that, with the antenna in one certain spot, I could receive 24 DTV channels, but not channel 8 (RF 8) or 19 (RF 10). Some of the stations I am receiving are stations listed in Antennaweb's charts with a violet marker, meaning that a high-power, amplified outdoor antenna must be used to get reliable reception of said stations. Why I am getting these stations "just like downtown" with an indoor antenna is beyond me, but I'm not complaining.

Since I watch channels 8 and 19 most of the time (their subchannels carry Antenna TV and MeTV, respectively), however, I have gone back to cable for the time being, until such time as the reception difficulties at both stations are no longer a problem in my area. Since these stations are almost certainly losing a substantial number of viewers due to these reception problems (many people cannot afford cable, even broadcast basic cable, or satellite, and so have no other choice but to use an antenna), I would hope the stations' owners would do whatever they had to do to improve their signals so that they will cover the entire northeastern Ohio area with few or no gaps or dead spots. Any television station which is affiliated with a major network, after all, cannot afford to be in a situation in which some parts of what should be its normal reception area do not get a usable signal from that station. I'm sure channels 8 and 19 are losing goodness only knows how much advertising revenue because of these reception problems; for that reason, again, I hope they do whatever is necessary to resolve these difficulties.

I don't think the amount of lost revenue will be anywhere near enough to put the stations out of business (both are owned and operated by large media groups), but it isn't doing them any good, either. CBS is currently America's #1-rated TV network, so it is very important that its affiliates reach as much of their coverage area as possible.
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Last edited by Jeffhs; 01-28-2015 at 11:25 PM.
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  #18  
Old 01-28-2015, 10:48 PM
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[EDIT- Correcting myself - 5 MW analog is correct - I really did not recall that.] Have to check, but I don't think I've heard of a 5 MW analog station - I think the limit was 1 or 2 MW.

Current limit for high UHF digital is 1 MW, but that can be restricted on the east coast where geographic packing is tighter.

VHF digital is a problem with low allowed ERPs because the FCC planning software did not take ambient noise into account correctly. VHF is also a problem because if you do turn up the power, you get enough over-horizon propagation to cause interference to other VHF stations on the same channel.

Last edited by old_tv_nut; 01-28-2015 at 10:53 PM.
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  #19  
Old 01-28-2015, 11:40 PM
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Quote:
Originally Posted by Jeffhs View Post
The ERP analog transmitter output for this station, as shown on the FCC's listings, is 3.1 kilowatts; the DTV signal's ERP either is not mentioned or I didn't see it in the listing the first time around. I'll have to look at it again; it could very well be that the DTV power level is substantially lower than the analog ERP was.
Right here on the FCC site, 3.5 kW ERP:

" Licensee: WOIO LICENSE SUBSIDIARY, LLC
Service Designation: DT Digital television station

Transmit Channel: 10 192 - 198 MHz Licensed
Virtual Channel: 19 (viewer sees this channel number)

Network affiliation: CBS

File No.: BLCDT-19991110AAR Facility ID number: 39746
CDBS Application ID No.: 428322

41° 23' 15.00" N Latitude Site in Canadian Border Zone
81° 41' 43.00" W Longitude (NAD 27)

Polarization: Circular (H = V)
Effective Radiated Power (ERP): 3.5 kW ERP
Antenna Height Above Average Terrain: 304. meters HAAT -- Calculate HAAT
Antenna Height Above Mean Sea Level: 567. meters AMSL
Antenna Height Above Ground Level: 293. meters AGL"

For another web study on reception in your area, try 'TV Fool", but I suspect the results will be about the same, however : http://www.tvfool.com/

jr

I also gather , from reading through some of the applications on the "Application List" that the station is indeed, now running 9.5 kW ERP (and has for several years) under the authority of a Special Temporary Authority (STA).

.

Last edited by jr_tech; 01-28-2015 at 11:46 PM. Reason: add info on 9.5 kW ERP STA
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  #20  
Old 01-29-2015, 11:45 AM
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Quote:
Originally Posted by jr_tech View Post
Right here on the FCC site, 3.5 kW ERP:

" Licensee: WOIO LICENSE SUBSIDIARY, LLC
Service Designation: DT Digital television station

Transmit Channel: 10 192 - 198 MHz Licensed
Virtual Channel: 19 (viewer sees this channel number)

Network affiliation: CBS

File No.: BLCDT-19991110AAR Facility ID number: 39746
CDBS Application ID No.: 428322

41° 23' 15.00" N Latitude Site in Canadian Border Zone
81° 41' 43.00" W Longitude (NAD 27)

Polarization: Circular (H = V)
Effective Radiated Power (ERP): 3.5 kW ERP
Antenna Height Above Average Terrain: 304. meters HAAT -- Calculate HAAT
Antenna Height Above Mean Sea Level: 567. meters AMSL
Antenna Height Above Ground Level: 293. meters AGL"

For another web study on reception in your area, try 'TV Fool", but I suspect the results will be about the same, however : http://www.tvfool.com/

jr

I also gather , from reading through some of the applications on the "Application List" that the station is indeed, now running 9.5 kW ERP (and has for several years) under the authority of a Special Temporary Authority (STA).

.
This is all well and good, but I cannot understand most of the information. That FCC website was intended for broadcast engineers, not ordinary people like myself. All I know or care about at this point is that I do not get channel 19 (or channel eight) without cable.

I also tried the other site you mentioned (TVFool.com), but I cannot use that one either because I do not know the latitude and longitude of the area in which I live. Isn't the name of the village (or the city closest to it) enough? Why do I have to mess with those other numbers? If channel 19 is running at 95 kilowatts, I should be getting it here just using a piece of wire connected to where the antenna goes, and I wouldn't have to use the amplifier in my DTV indoor antenna.

Honestly, I wish the FCC had left the country's television system alone. The old NTSC analog system served us well for over 50 years; now we have a DTV system that doesn't work for many people without cable. I like my TV, don't especially care anymore how my favorite shows get here (meaning I don't care about the technical stuff behind DTV), and do not appreciate all this trouble I have to go to just to get the two channels I watch more than any other TV station in Cleveland.

Is there any chance the FCC will realize what a flop DTV is in most areas, and revert to the NTSC analog system? At least with that system there was a picture if your TV signal was weak; with digital, it is all or nothing. I like DTV from the standpoint of a clearer picture and more channels, but I can do without the reception problems.


Sheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeesh!!
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Last edited by Jeffhs; 01-29-2015 at 11:50 AM.
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  #21  
Old 01-29-2015, 12:22 PM
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Quote:
Originally Posted by Jeffhs View Post
I also tried the other site you mentioned (TVFool.com), but I cannot use that one either because I do not know the latitude and longitude of the area in which I live. Isn't the name of the village (or the city closest to it) enough? Why do I have to mess with those other numbers? If channel 19 is running at 95 kilowatts, I should be getting it here just using a piece of wire connected to where the antenna goes, and I wouldn't have to use the amplifier in my DTV indoor antenna.
The TV Fool website will take an address or even just a zip code... I tried it just using 44077 zip and it showed a *very* weak signal on channel 10 in the area. Address or coordinates should get results that are more specific to your location.
You must have miss-read the power that I stated; it is 9.5 kW ERP *not* 95!

jr
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  #22  
Old 01-29-2015, 12:27 PM
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Is there any chance the FCC will realize what a flop DTV is in most areas, and revert to the NTSC analog system?

Don't hold your breath!

I do miss analog TV, and liked that old TVs were still able to operate on their own without external equipment, but I have to say that I also really enjoy free over-the-air HD. I also really like the extra sub-channels and the networks that have sprung up to occupy them.

It is a conundrum, to be sure. The all-or-nothing nature of digital certainly is a hassle, and the broadcast radius has shrunk when the stations went to DTV. In very rural areas, they have set up retransmission stations to help with coverage, but most other places just have smaller coverage area now.
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  #23  
Old 01-29-2015, 06:52 PM
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9.5kW ERP probably means a transmitter output power of ~1500W. Hell, I just looked it up, its 1610 watts at the transmitter output. You're not going to get squat off of that at your bearing and range. (Remember, that power is spread evenly over the WHOLE 6MHz channel slot, and the gain of the antenna only helps you if the main lobe is pointed towards you, which it isn't.) Don't worry though, the FCC is planning another re-shuffle and spectrum consolidation operation in the next few years.
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  #24  
Old 01-29-2015, 08:36 PM
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Quote:
Originally Posted by NoPegs View Post
9.5kW ERP probably means a transmitter output power of ~1500W. Hell, I just looked it up, its 1610 watts at the transmitter output. You're not going to get squat off of that at your bearing and range.
I am not following you. It still doesn't make sense to me. Why would I not get the station at "my bearing and range", whatever that means? That television station, like every other Cleveland television station, is licensed to and is obligated to cover all of northeastern Ohio. What will I have to do to get the station, and channel eight, with an antenna, like I did years ago when I lived in an eastern Cleveland suburb? Even 15 years ago, when I moved here from that suburb, I could get channel 19 fairly well on an indoor antenna; in fact, that was the only station I could receive well enough to watch. Then, of course, all TV was still NTSC analog.

Channel 3 was the one station that I couldn't receive here; five, eight, 25, 43, 55, and 61 weren't that much better. This was in 1999, long before the DTV transition. I can get all the Cleveland stations on cable (Time Warner broadcast basic service), although I don't especially like that due to the rate increases every year. That was why I bought the Zenith indoor DTV antenna; I was hoping I could do away with cable for good. Is there any kind of indoor TV antenna that will bring in every TV station in my area, including eight and 19, or am I stuck with cable and its rate increases? I don't want to have to bother with erecting an outdoor antenna.

BTW, I wonder why the Zenith antenna doesn't work at all on one of my NTSC analog televisions. I realize there is no more analog TV since the transition, but I was hoping I would at least see a translator station or two; however, as I mentioned in my post, when I connect the antenna to my RCA TV and do a channel scan, the tuner goes from channel 2 to the highest channel it will receive, without stopping. If left alone, the tuner then loops back to channel 2 and will repeat the cycle indefinitely. I know the TV is working, as I can connect it to the cable outlet in my bedroom and it receives every station on the cable.

I have not tried the Zenith antenna on my nearly-20-year-old Zenith SMS1917SG 19" CRT TV, although if I did I would probably, almost certainly, get the same results I had with my RCA set.

It was suggested to me by someone in this thread that I consider using an ATSC-to-NTSC converter box with my Insignia 19" flat screen, which already has its own clear-QAM tuner. My question is simply this: Are the QAM tuners built into many if not most flat screens that terrible as far as RF sensitivity is concerned?

I may take a look on eBay tonight to see if I can find a reasonably good DTV converter box. Are there any particular brands I should avoid? I've read here that some off-brand converters, such as Apex and even Magnavox-branded boxes, are poor choices because of low RF sensitivity and that they run hot, contributing to early failure. Are there any really good DTV boxes still available, or has the market more or less dried up since new flat screen TVs can be purchased at dirt-cheap prices now? I've seen some flat screens selling for well under $100; I saw one recently in an ad flyer in my Sunday paper that was selling for $88. Even large-screen flat panels are selling for far less than they were even as recently as a year ago; I saw a 32" Insignia TV in a Best Buy ad that was priced at $130--the same price I paid for my 19" Insignia almost four years ago. Makes me think at least twice before considering having my set repaired if it someday needs service. This set has given me excellent service so far, though; I'm not expecting any trouble with it, but if and when it does go bad I'd likely be better off buying a new one, especially since finding out I can get a larger screen today for the same money I paid for my set back in 2011, and they are likely to keep coming down in price--so why bother having a set repaired anymore once it's out of warranty?
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Last edited by Jeffhs; 01-29-2015 at 10:55 PM.
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  #25  
Old 01-29-2015, 11:22 PM
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"It was suggested to me by someone in this thread that I consider using an ATSC-to-NTSC converter box with my Insignia 19" flat screen, which already has its own clear-QAM tuner. My question is simply this: Are the QAM tuners built into many if not most flat screens that terrible as far as RF sensitivity is concerned? "

Clear QAM tuners are only for unscrambled digital cable, not for over the air. QAM is not broadcast over the air, only ATSC 8-VSB. As most cable companies are taking to scrambling everything, there may not even be any clear QAM signals on your local cable system anymore.
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Old 01-30-2015, 12:10 PM
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Originally Posted by old_tv_nut View Post
"It was suggested to me by someone in this thread that I consider using an ATSC-to-NTSC converter box with my Insignia 19" flat screen, which already has its own clear-QAM tuner. My question is simply this: Are the QAM tuners built into many if not most flat screens that terrible as far as RF sensitivity is concerned? "

Clear QAM tuners are only for unscrambled digital cable, not for over the air. QAM is not broadcast over the air, only ATSC 8-VSB. As most cable companies are taking to scrambling everything, there may not even be any clear QAM signals on your local cable system anymore.
My cable operator is Time Warner. To the best of my knowledge and belief, they have no intention at this time of scrambling everything on the cable, thereby forcing all subscribers to use a cable box ahead of the television to receive anything at all. (Comcast does require boxes now, and Time Warner would today as well if their merger with Comcast had materialized, which it did not.)

I have broadcast basic service (not digital). The cable connects directly to my VCR, which in turn is connected directly to the TV. There are no descrambler boxes or anything else, again to the best of my knowledge, between the cable coming into my apartment and the VCR. If there are such devices being used by the company, they are probably on the utility pole outside my apartment or hidden away in a junction box in the basement of the building. I'm sure Time Warner would have notified me by now if they had any intention whatsoever of scrambling absolutely everything, including broadcast channels.
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  #27  
Old 01-30-2015, 03:34 PM
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Originally Posted by Jeffhs View Post

Is there any chance the FCC will realize what a flop DTV is in most areas, and revert to the NTSC analog system? At least with that system there was a picture if your TV signal was weak; with digital, it is all or nothing. I like DTV from the standpoint of a clearer picture and more channels, but I can do without the reception problems.
Sorry, not gonna happen. The FCC wants much of the TV bands for other things anyway. Channels 52 to 82 became cell phone territory. And some for the police and fire depts, since 9-11. IIRC, channels 14 to around 16 in New York City are used for police and fire comms.
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Old 01-30-2015, 04:45 PM
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"That television station, like every other Cleveland television station, is licensed to and is obligated to cover all of northeastern Ohio."

Not true... There is an FCC-regulated obligation to have a certain level of signal in the stations "city of License" which is Shaker Heights but absolutely *no* obligation to cover all of northeastern Ohio.

" What will I have to do to get the station, and channel eight, with an antenna, like I did years ago when I lived in an eastern Cleveland suburb? "

Move! Sorry for the flippant sounding answer, but lets review the facts, you have tried 3 different indoor antennas that provided no reception on these 2 channels. Online reception prediction sites basically are predicting no reception with an indoor antenna, and you seem reluctant to install a proper outdoor antenna.

" Even 15 years ago, when I moved here from that suburb, I could get channel 19 fairly well on an indoor antenna"

According to information on the FCC site, at one time channel 19 had 3700 kW (YES 3.7 Million watts) of analog power... I don't know the history here (money problems, poor engineering, whatever) but they ended with 3.5 kW (or perhaps 9.5 kW by authority of a STA) on channel 10, which is limited in power because of a channel 10 in Canada... It seems to me as if some poor choices were made.

jr
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  #29  
Old 01-30-2015, 10:47 PM
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My cable operator is Time Warner. To the best of my knowledge and belief, they have no intention at this time of scrambling everything on the cable, thereby forcing all subscribers to use a cable box ahead of the television to receive anything at all. (Comcast does require boxes now, and Time Warner would today as well if their merger with Comcast had materialized, which it did not.)

I have broadcast basic service (not digital). The cable connects directly to my VCR, which in turn is connected directly to the TV. There are no descrambler boxes or anything else, again to the best of my knowledge, between the cable coming into my apartment and the VCR. If there are such devices being used by the company, they are probably on the utility pole outside my apartment or hidden away in a junction box in the basement of the building. I'm sure Time Warner would have notified me by now if they had any intention whatsoever of scrambling absolutely everything, including broadcast channels.
You have completely confused me. First you talk about inability to get over the air channels, then you bring up clear QAM, which is only for cable. Why are you asking about how good your clear QAM tuner is? Are you saying:
1) My TV has a tuner that can do BOTH clear QAM and over-the air VSB, and
2) I have heard that tuners that do both clear QAM and over the air are not very good at over-the air (?)

If that is your question, the answer is that both dual-purpose and single purpose tuners may be better or worse depending on the design. Being dual-purpose does not necessarily mean poor over-the-air results; but, a tuner with poor threshold would show a deficit on over-the-air sooner than on cable, which should have a decent signal strength.
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Old 01-31-2015, 08:03 PM
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Not to be curt, but your situation is exactly why cable television came into existence. Yes, I get drop-outs sometimes and you can physically see the transmitters through the window above the set. Yes, in the days of NTSC I could pickup color programs off the antenna screws. All that's gone forever.
I'm currently planning a move out of town into a more rural area. While I will most certainly install some huge antenna to play with, I do not expect to reliably receive ATSC 30-50 miles out, and am prepared to subscribe to cable again if needed. I know you're in an apartment, so unfortunately your choices are to accept what OTA you can receive, keep cable or move back to Cleveland. Nothing short of a big rooftop job is going to pull in that CBS affiliate.
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