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Old 03-13-2012, 12:48 AM
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ClearCast HDTV indoor antenna -- overhyped?

Greetings.

I saw an article yesterday (February 12, 2012) in my local newspaper (the ad is probably being run in newspapers across the U. S. as well) for a revolutionary new type of indoor TV antenna, from a company known as ClearCast. The company claims that this antenna will pull in up to 53 channels of TV in almost any reception area, even rural areas that presently receive (over the air) only NBC, ABC, CBS, FOX and PBS programming and may not have access to cable or satellite services. The antenna is wafer-thin and can be mounted anywhere in a room (preferably on or near a window) by means of suction cups, so no installation is required -- simply mount the antenna on/near the nearest window, connect the coax lead-in to your TV, and (supposedly) enjoy all the local TV stations your cable company presently delivers to your home for a (very high) fee that only seems to go up.

I live in a village of about 3250 population, located roughly one mile from the southern shore of Lake Erie and just under 40 miles from the seven TV transmitters serving Cleveland. The village is 610 feet above sea level. My question is simply this: will the ClearCast indoor HDTV antenna work in this area, or will it be a dud? (The company representative with whom I spoke over the phone and who took my order assured me that the antenna would, in fact, work in my area -- but still I have doubts.) I did check local antenna reception here some years ago (before the DTV transition), using a beat-up pair of TV rabbit ears without a UHF loop; I was able to receive only two stations (CBS WOIO 19 in Cleveland and a translator station, probably relaying a local religious TV station) well enough to watch, although I did have fair to poor reception of the other six local network affiliates including PBS.

That was then; this is now. I just (as in yesterday afternoon) ordered a Clear Cast indoor HDTV antenna, and will be awaiting its arrival. I will post the results of my experiments with the new antenna as soon as it arrives and I have had a chance to see just how many stations I can receive with it, hooked up to my flat screen.

I read an article online yesterday afternoon from a Syracuse, New York newspaper, however, that said antennas of this type are typically no better than the buck-and-a-half UHF bow-tie clip-on indoor ones that used to be available at Radio Shack and elsewhere, not to mention the even cheaper UHF loop antennas which were formerly provided with most new televisions in the late 1960s-'70s, when UHF TV was just getting started in this country.

Are the claims for the Clear Cast HDTV indoor antenna true, or are they just meaningless, overblown hype? Has anyone here on VK ever tried this or any other type of indoor HDTV antenna, and if so, what were your results and impressions? Are indoor HDTV antennas even worth their asking price, or are they junk, not unlike those gutless-wonder indoor TV antennas of the '60s disguised to look like oil lamps, animals, and the like? In those days, television signals were NTSC analog, and in many cases, good reception (even in color, in good signal areas) could be attained using rabbit ears, even if it meant buying a fancy Rembrandt all-channel antenna with huge UHF loops and a 12-position fine-tuning switch.

I am also eager to see if I can receive (using an indoor HDTV antenna, once my new Clear Cast one arrives here) the subchannels of the Cleveland network affiliates, as three of these stations now have subchannels (MeTV, Antenna TV and This TV, plus two subchannels of the Cleveland PBS station) I now get on cable. Are the subchannels separate low-power TV stations in their own right, or are they simply extensions (for want of a better word) of the parent station's main signal?

Thanks in advance.
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Last edited by Jeffhs; 03-13-2012 at 12:54 AM.
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Old 03-13-2012, 02:12 AM
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I ran TV Fool for Fairport Harbor and it predicted that you should be able to get a few channels with an indoor antenna (those highlighted in green)... try it for your specific address:

http://www.tvfool.com/?option=com_wr...0b8604ad48d044

My guess is that it mostly hype in the antenna ad, and it likely will not perform better than a simple rabbit ear antenna. Don't expect too much! Anyway, it should be an interesting experiment!

The sub-channels of the ATSC transmission are all part of the same digital stream... if you can receive the main channel, you should get the sub-channels as well.

just my 2 cents worth,
jr
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Old 03-13-2012, 12:45 PM
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I'm not going to expect miracles from this antenna; I'm just interested in how well it may or may not work in my area. I've never used my flat TV with an antenna (it has been on cable since it was new last August), so this should be an interesting and enlightening experiment.

I don't expect to get, with this indoor antenna, the stations listed on TVFool as being 50+ miles from me, but then again all I'm really interested in are the Cleveland network stations and their subchannels (MeTV, Antenna TV and two subchannels of Cleveland's PBS affiliate). If the antenna brings in these stations, the transmitters for which are all over 30 miles from my apartment according to TVF's charts, I will be happy. (The distance is just under 40 miles if you look up, on Google Earth, the distance between Fairport Harbor and the two southwest Cleveland suburbs in which Cleveland's seven TV stations' transmitters are located; I don't know why TVFool is showing the stations as being just 30+ miles from here).

I will not cancel my cable, however, until I have conducted this experiment and have a concrete idea of how well the ClearCast antenna works. I had never heard of this antenna until I saw the advertisement for it in my newspaper last night, and as I said in my last post, I also read online an article from a Syracuse, New York paper that had less-than-glowing reviews of the antenna. It stated pretty much what you said at the end of your post: the ClearCast will not work much better, in most signal areas, than a cheap UHF bowtie antenna.

I also noticed, when I took a closer look at the ClearCast antenna in the ad, that it seems to be useful only for those DTV stations currently operating on UHF channels; I did not see any provisions for reception of VHF DTV channels as well. This may put me at a disadvantage and may give me another reason not to be too hasty about cancelling my cable service, as one Cleveland station (WOIO CBS 19) currently operates on DTV channel ten. There has been talk of changing this to a UHF channel due to possible interference issues with a Canadian TV station on the same channel (CFPL in London, Ontario, across Lake Erie from Cleveland), but nothing has been done yet.

However, I wonder if the designers of the ClearCast indoor HDTV antenna are under the impression that all TV stations in the United States have transitioned to UHF DTV channels by now. As I mentioned, however, this is not necessarily the case. There are still some areas with DTV stations on VHF channels, although such stations are likely in the minority these days.

WOIO CBS 19 in Cleveland, however, does have a new translator station on DTV channel 24 for the Akron area, but I don't think I'll see it here with just the ClearCast antenna due to the distance involved -- over 50 miles from me.

One problem with TV reception in my area is the sheer distance from here to the Cleveland TV transmitters; most people here have either satellite or cable, with the few outdoor antennas left (there are a few still standing) falling apart from disuse and/or age -- some of these antennas are as old as the houses on which they are mounted, and there are some very old houses in this town, dating to the '50s and earlier. I have even seen conical VHF-only antennas here that date to the '50s; of course, most of them have fallen apart by now (I saw one last summer that was little more than a boom on a mast -- most of the elements had blown off in wind and snow storms) and are now worse than useless.

Antenna reception here may not have been much of a problem before DTV (just put up a good near-fringe antenna and you were good to go for the three original Cleveland VHF TV stations, with UHF following in the '60s and '70s), but the arrival of this new broadcasting standard nearly three years ago has changed everything. This is why most people today, even those folks living in cities or their suburbs, have cable or satellite service -- because they just don't want to be bothered with putting up antennas and the reception problems attendant to OTA DTV. I don't blame them.
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Last edited by Jeffhs; 03-13-2012 at 12:50 PM.
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Old 03-13-2012, 01:38 PM
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Quote:
Originally Posted by Jeffhs View Post
(The distance is just under 40 miles if you look up, on Google Earth, the distance between Fairport Harbor and the two southwest Cleveland suburbs in which Cleveland's seven TV stations' transmitters are located; I don't know why TVFool is showing the stations as being just 30+ miles from here).
TV Fool uses the co-ordinates of the transmitter site, not those of the nearest suburb in making the calculation. For example, WKYC-DT might be closer than you calculate... here is a map (with scale) from the FCC site:

http://maps.google.com/?q=http://tra...26state=OH.kml

jr
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Old 03-13-2012, 02:44 PM
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Jeff, Thanks for starting a good discussion here. Try this site also: http://transition.fcc.gov/mb/engineering/maps/

Of particular note, you probably will also get about half the "pink" stations with a good Winegard or similar ROOFTOP antenna.

I will refrain from a rant about OTA DTV and the number of channels I now get out in Amish Country. Results may vary.
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Old 03-14-2012, 01:07 AM
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First results of DTV antenna reception test

I hooked up a length of zip cord today to a rebent coat hanger and poked the end of the wire into the center pin of my TV's antenna socket, just to see if I could get any OTA DTV signals here. My flat screen found five digital channels during a channel scan using this makeshift DTV antenna, and to my surprise, the reception on those five channels is excellent.

As has been noted with DTV, antenna position plays a large part in getting a good signal; I found that as I moved the antenna around my apartment, the picture on my TV would change, in every case becoming perfectly watchable with the antenna in one particular spot. I even picked up one subchannel of Cleveland's MyTV affiliate that I hadn't seen before, as my cable doesn't carry it -- yet.

To my surprise, I was not able to receive the DTV signal of WOIO-CBS 19 in Cleveland with my makeshift test antenna, although I was getting the city's NBC and ABC stations, and the Univision affiliate, just fine. I don't know if it is because the CBS station's DTV signal is on a VHF channel while the others are on UHF channels, or just what the problem was. My flat TV has only one antenna input for all signals, so I would think any antenna I'd hook up would pick up signals in both bands, with lowered sensitivity, of course, on the frequency range for which the antenna is not designed. I'll have to keep that in mind when my Clear Cast DTV indoor antenna arrives, as it seems to have been designed for UHF reception only (the picture of the antenna in the newspaper ads shows the outline of a UHF bowtie antenna plainly visible on the front of the plastic casing).

While the Clear Cast antenna will undoubtedly work somewhat better than my makeshift DTV one did, however, it will be no match for a roof-mounted Winegard or other standard television antenna. Since I live in an apartment building, I cannot erect outdoor TV antennas, although two of my neighbors have satellite dishes -- one on the roof of the building, the other in back of the building on a railing.

As I mentioned in my initial post that started this thread, I am not expecting miracles with the Clear Cast DTV indoor antenna; I am simply curious to see what I can expect, using an indoor antenna in a first-floor apartment. My first experiments with the rebent coat hanger gave me a very rough idea, but I am sure the new antenna will work much better and will probably bring in channel 19 -- as well as the PBS station in Cleveland and its subchannels, not to mention every other major network station in town.

BTW, one very good feature of digital TV, IMHO, is that if you get a picture, it will be perfect; however, if there is no signal or your antenna is in a dead zone, your screen will be blank. There is no in-between where the image is fuzzy or snowy; no ghosts, either. The DTV equivalent of snow in an analog TV picture is when a DTV image pixelates, breaking up into squares; the sound will also be affected.

However, with a good clear signal, a DTV picture looks great, like a good photograph. An ad on Zenith's website (www.zenith.com) for their DTV converter boxes, in fact, states that "your old TV has never looked better" than when it receives a DTV signal.

I am looking forward to continuing my DTV experiments and will continue to post the results here. As of now, using the makeshift DTV antenna, I can get the following stations:

Channel 3.1 -- WKYC-HD (NBC) Cleveland
Channel 3.2 -- WKYC Weather Radar
Channel 5.1 -- WEWS-HD (ABC) Cleveland
Channel 5.2 -- LiveWell Network
Channel 43.1 -- WUAB-HD (MyTV)
Channel 43.2 -- THIS TV
Channel 43.3 -- Bounce (new subchannel)
Channel 61.1 -- WQHS-HD (Univision) Cleveland

There are at least two local stations my makeshift antenna doesn't get, regardless of where I put it: CBS 19 WOIO, WVIZ PBS 25.1. Again, I'm thinking it is just the haywired nature of the antenna that's keeping me from receiving these channels; the new Clear Cast antenna should bring in every station in Cleveland, including the subchannels. The new antenna will be mountable on a window or wall by means of suction cups, not to mention having a much longer lead-in cable, so I will be able to try it in more locations in my apartment than I could with the makeshift antenna. I should then be able to find out where my channel 19 and 25 signals are hiding.
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Last edited by Jeffhs; 03-14-2012 at 11:22 AM.
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Old 03-14-2012, 02:35 AM
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Great!
It will be very interesting to compare the new antenna to this baseline data. At least you have proven that you can get a few channels OTA, further experimentation is likely to improve results.

You might want to check 43 again, as there is one more sub-channel to be found there:
43.1 WUAB-HD
43.2 Bounce TV
43.3 This TV

PS: The VHF channels seem to be more difficult to receive in most areas. Many have filed with the FCC for power increases, or to move to UHF. WOIO has a construction permit for a 3X increase in power and more height, which should help.

http://transition.fcc.gov/fcc-bin/tv...=0&facid=39746

Good luck,
jr

Last edited by jr_tech; 03-14-2012 at 03:04 AM. Reason: add ps
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Old 03-14-2012, 11:43 AM
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Jeff-

As we hams know , the more and the higher and the less-obstructed metal we put in the air, the better! If that "Clearcast" antenna is what it appears to be (some type of panel device about 15 inches by 4 inches, with a coaxial cable to connect to the TV), then it should work no better and no worse than a basic wire folded dipole (tuned to the UHF TV band) or similar item made into a shape not exceeding 15"x4".

In the NTSC days, I used to help local friends in apartments with bad TV reception by building 300-ohm folded dipoles cut for the low-VHF-TV band out of basic twin-lead wire (with a 75-ohm matching transformer for the newer TVs' coax input jacks). We would hang them horizontally near a window (behind the top of the curtains was a good place) and everyone would be amazed how much better this worked than the three or four fancy-looking amplified antenna gadgets they had tried from Radio Shack or elsewhere by then.

I live in a location between San Jose, San Francisco, and Oakland, California, and with a pair of 1950s rabbit ears connected to my 1948 RCA 8TS30 or 1965 CTC-16, I get every digital channel in the area (with a digital tuner in between, of course). Simple is often the best.
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Old 03-14-2012, 12:13 PM
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Quote:
Originally Posted by jr_tech View Post
Great!
It will be very interesting to compare the new antenna to this baseline data. At least you have proven that you can get a few channels OTA, further experimentation is likely to improve results.

You might want to check 43 again, as there is one more sub-channel to be found there:
43.1 WUAB-HD
43.2 Bounce TV
43.3 This TV

PS: The VHF channels seem to be more difficult to receive in most areas. Many have filed with the FCC for power increases, or to move to UHF. WOIO has a construction permit for a 3X increase in power and more height, which should help.

http://transition.fcc.gov/fcc-bin/tv...=0&facid=39746

Good luck,
jr
Thanks for the info on WOIO's proposed changes. A 3x power increase (the station now transmits 3.72kW effective radiated power [ERP], the same power level as when it initially signed on in mid-1985) and higher antennas will almost certainly improve reception throughout the station's coverage area, especially in near-fringe locations such as Fairport Harbor and points east to the Pennsylvania border. This station has had problems for years with poor reception in some areas west and east of Cleveland (mainly far east and west suburbs and outlying areas), but at that time, being a new station, it may not have been able to get authorization for power increases or antenna changes.

Why WOIO transmits on DTV channel ten is beyond me, since most TV stations now operate on UHF digital TV channels and there is already a Canadian station (CFPL in London, Ontario) on the same VHF channel; the possibilities for co-channel interference would seem to be too great. I would have thought WOIO would have been assigned a UHF DTV channel from the beginning. The station's UHF translator on channel 24 is no help to the Cleveland area, as it is intended to serve the Akron-Canton area which is some 30 miles southwest of Cleveland.


Thank you also for the information on WUAB's second subchannel, THIS-TV on 43.3. My cable carries this channel, so I have been aware of it for some time; however, I neglected to include it in my list of received stations using my haywired makeshift DTV antenna, probably due to an oversight on my part.


I just remembered that WOIO has done quite a bit of work already on its transmitter and antennas to address, and hopefully resolve, the reception problems I mentioned. I don't know if the info is still there (it's been some time since the modifications were made), but there was a notice on the station's website (www.19actionnews.com) to the effect that work was in fact underway at that time to increase the transmitter's ERP output (probably a new transmitter) and to raise the station's antennas, the end result being to put a stronger, better signal into the areas in which WOIO has had reports of poor or no reception since the DTV transition.
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Old 03-14-2012, 03:37 PM
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Why WOIO transmits on DTV channel ten is beyond me, since most TV stations now operate on UHF digital TV channels and there is already a Canadian station (CFPL in London, Ontario) on the same VHF channel; the possibilities for co-channel interference would seem to be too great.
One word here... MONEY! In general, It is cheaper to operate a lower power VHF station than a UHF station that must operate at higher power levels to obtain the same coverage. It was also likely cheaper to leave the digital on channel 10 after the transition date than to "flash cut" the digital back to the original analog channel (19) as I suspect that the channel 10 digital transmitter was a new purchase, while the channel 19 may have been a very old unit, not suited to digital transmission... but this is only a guess.

The problem... The Calculation of the coverage area appears to overstate the coverage of the VHF channels when compared to the UHF channels. This calculation was based on assumptions/projections (mostly about receiver capability) that were made 20 years ago when the standards were set. Some projections were not realized.

jr

Last edited by jr_tech; 03-14-2012 at 03:48 PM. Reason: add info
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Old 03-15-2012, 10:21 AM
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Jr Tech: The Calculation of the coverage area appears to overstate the coverage of the VHF channels when compared to the UHF channels.

Well stated and quite true!

The ATSC (8VSB modulated) signals seem to behave very differently, especially when subject to terrestrial challenges and weather variations. My personal example of the contrast here is the signals from Baltimore, 50 miles to the SW of our gently-rolling, open terrain. Philadelphia, 55 miles to our East has two VHF and ten UHF stations but requires a decent rooftop antenna. This is in addition to 7 "Harrisburg market" (2-VHF, 5 -UHF stations) received with a medium-sized, attic-mounted antenna. Rotators are much less helpful, since the local channels come in no matter where the antenna is aimed.

The Baltimore example....

Analog: VHF channels 2, 11, 13 were fairly stable while UHF channels 24 & 54 were weak, yet 45 was fairly good (like the VHF's) due to a higher antenna and power than the other UHF's.

Digital: 11 and 13 retained (and returned to) their VHF spots, but cannot be received most of the time, even with a VHF log-periodic rooftop antenna and booster. WMAR-2 is on UHF-38 (using a new antenna and transmitter no doubt) and easily received, even with a modest UHF rooftop antenna.
54 (DT-40) and 24 (DT-41) are a bit weaker but still consistently received. 45 (now on 46) is rarely received although the transmitting power and antenna height are unchanged.

Now we change to a very different location at a hunting lodge along a creek, "upstate" in a deep, wooded valley between Binghampton NY (50 miles away) and Wilkes Barre (37 miles away);

Analog: VHF channel WBNG 12 from Binghampton was fair using a HB-VHF 10-element yagi, no other channels were received.

Digital: VHF channel WBNG-DT 7 is fairly reliable and WICZ-DT 8, also from Binghampton at much lower power is received a majority of the time. No UHF channels from either city were received, even while using a Winegard 7694 and booster presumably due to the deep woods.

Note: Electronic ballasts in T8-lamped fluorescent kitchen lights must be switched off when watching WICZ.

Conclusions: VHF seems better suited to areas with severe multipath but the range seems poor over open terrain. Weather affects VHF even more than before. Less signal strength is required to "acquire" DT reception, so UHF performance seems better, at least in more open areas not subject to much multipath.
DT recievers (HD sets and converter boxes) seem to have much less interference rejection that analog stuff did. Electronic ballasts, especially for higher-wattage compact fluorescent 3&4 tube fixtures really cause problems similar to weak FM stations. The screw-in CFLs are lower power and thus not much of an issue.

Last edited by DavGoodlin; 03-15-2012 at 10:24 AM. Reason: error
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Old 03-15-2012, 03:50 PM
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Your observations align well with mine. I am close in (12 Miles to the antenna farm) and don't have much trouble with reception, although it seems to be more difficult to receive the VHF channels using the built-in monopole antennas on portable sets in some rooms of the house. These antennas are really too short to be very effective at high band VHF frequencies. In stormy weather, I see more "breakup" on the UHF channels, likely due to wet blowing trees.

My one "DX" channel is about 70 miles distant on ch 7... Analog era, it was decent with a moderate sized outdoor Hi band Yagi... during the transition period the digital was on UHF channel 37(?) and was great with a moderate sized Radio Shack corner reflector/Yagi. After the transition/analog shutdown the station returned to ch 7 (digital) and I can only receive it on rare occasions (mostly early mornings and late evenings) using the Hi band Yagi. The contour maps shown on the FCC site are virtually identical for all three permutations of the channel.

Found this article, with much hindsight, discussing some of the problems related to the standards that were set 20 some years ago:

http://www.tvtechnology.com/article/...d-power/203114

jr

Last edited by jr_tech; 03-15-2012 at 09:01 PM. Reason: add info
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Old 03-15-2012, 10:56 PM
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Quote:
Originally Posted by jr_tech View Post
The problem... The Calculation of the coverage area appears to overstate the coverage of the VHF channels when compared to the UHF channels. This calculation was based on assumptions/projections (mostly about receiver capability) that were made 20 years ago when the standards were set. Some projections were not realized.

jr
The calculations were based on a rooftop antenna with a decent gain at VHF, but most importantly neglected the high levels of manmade noise and interference and "atmospheric" noise in the VHF band. The receivers themselves have about the same sensitivity on all channels. When you go to an indoor antenna, which generally must be too small for VHF performance to equal UHF, plus taking attenuation due to lower height above ground, plus building attenuation, reception suffers. I can get reception at 38 miles from Chicago with an amplified indoor antenna on channel 12 and even channel 7, **on the second floor**, but not on the first floor. (This antenna has quite long dipole rabbit ears for VHF). The antenna I have in my attic picks up everything. The line of sight is through a neighbors' house kitty corners from me and some tall trees behind that.

When reception is truly impossible, it usually involves being behind terrain or over the horizon - the signals just don't go through dirt. On analog, some reception was possible by diffracted signals. The VHF coverage for digital (and hence the radius of interfering with other stations) was predicted to follow a similar result (except for the all-or-nothing nature), and therefore the VHF stations' power was reduced drastically compared to analog to prevent long-distance interference. (UHF is more predicatably limited to somewhat beyond the horizon.) Now that practical results are in, stations are asking for power increases, which have to be considered in the light of will they cause interference to other stations. Plus, increases along the northern tier of states have to be coordinated with Canada.

There were a few cases of digital low VHF signals (especially over water) interfering with analog VHF on the same channel before analog was shut off. With analog shut down, there is more possibility of adjustment.
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Old 03-16-2012, 10:46 AM
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Co-channel interference and other such noise

Thanks OldTVnut for co-channel interference;

NYC and Baltimore/DC both had the same analog channels. Baltimore is 160+ miles from NYC, with DC's transmitters (chs. 4,5,7,9) an additional 36 miles. Rare co-channel interference was noted only during summer e-skip periods by the venetian-blind effect and strange whine in the sound.

After digital transition, original channels 11 and 13 remain in NYC and in Baltimore. No other analog channels 11 & 13 were in the mid-atlantic.
But....Wilkes Barre, PA (100 miles WNW of NYC and 130 miles NNE of Baltimore) also moved formerly UHF WBRE and WYOU to these channels! Talk about a crowded spectrum!

My loss: I received analog UHF's of WBRE and WYOU near perfect, even 83 miles away. Now I only get the UHF channels (same mountain transmitter farm) but WBRE and WYOU only a few days per month based on weather.

After consultation of other forums, I have concluded that VHF-DT will never provide the same coverage area as Analog VHF, where a 75 mile range was common and necessary.

Co-channel and noise IS the silent killer of DT reception. Its presence can only be discovered by using a spectrum analyzer, which I do not own.

As for UHF, trees and dirt are STILL formidable obstacles.
trees-and-uhf-reception.pdfSee attached article from UK expert.
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Old 03-16-2012, 01:01 PM
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One word here... MONEY! In general, It is cheaper to operate a lower power VHF station than a UHF station that must operate at higher power levels to obtain the same coverage....
jr
Also most viewers get their signals via cable TV, and thus all a TV channel need do is just have a presense on the RF spectrum, and "must carry" rules are invoked. So the TV channel need not worry too much about reception problems, and cutting the electric bill by using lower power on VHF would make sense, as the cable company still will pipe the channel over their system to most viewers. Non cable subscribers are likely not that interesting to advertisers anyway "If they don't want to spend money on cable service, they probably won't spend the money to buy our product..."
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