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  #16  
Old 01-12-2012, 12:57 PM
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Most stations may have switched to UHF digital channels, but there are a few holdouts. For example, in my area, channels 3 (NBC) and 5 (ABC) are on UHF digital assignments but the DTV channel for CBS channel 19 in this area is actually VHF channel 10. Moreover, channel 8, the FOX affiliate here, is still on a VHF digital channel but will eventually move to, IIRC, channel 31, if I am to believe what I have been reading lately on Ohio Media Watch. Channel 19 has no plans that I am aware of to move its DTV assignment to UHF, although since this area is close to Lake Erie and a Canadian TV station on channel 10, the Cleveland station might well interfere with the latter, even though Canada's DTV transition is complete.

I am surprised channel 19 did not either stay on its original channel position (or else move to another UHF channel) after the transition. It would have made more sense for this station to have remained on 19, as did a station 60 miles south of here on channel 23. The latter, the ION television network affiliate for this area, was able to remain on 23 even after the DTV switch. I don't know how it is possible for a television station to switch from analog NTSC to ATSC digital while remaining on the same RF channel, but somehow 23 did it.
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  #17  
Old 01-12-2012, 02:23 PM
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Quote:
Originally Posted by Jeffhs View Post
I don't know how it is possible for a television station to switch from analog NTSC to ATSC digital while remaining on the same RF channel, but somehow 23 did it.
Technically it is very easy to change from analog to digital just by swapping exciters, although meeting the strict out-of-band radiation limits could prevent doing it that simply (some high-level filtering may be required). A few stations (mainly public broadcasting, I believe) requested and got permission to do a direct cut with no transition period of dual broadcasts. In one of the cases I read about, they determined that only 3% (IIRC) of their audience was using the over-the-air signal, since they were serving a large state-wide area rather than a single concentrated urban population.
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  #18  
Old 01-12-2012, 11:32 PM
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Jeff-

Maybe that station went from NTSC channel 23 to "pretend" 23 (but actually on another UHF channel) when it was first in digital, especially if it kept its analog signal on the air until 2009 as most stations did. Then, when the NTSC was shut off, the digital signal could have been moved to true channel 23. Two of the stations here in the S.F. Bay Area did this, so their signals are now really on the numbers they use (channels 7 and 36).
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  #19  
Old 01-13-2012, 12:14 AM
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Originally Posted by ChrisW6ATV View Post
Jeff-

Maybe that station went from NTSC channel 23 to "pretend" 23 (but actually on another UHF channel) when it was first in digital, especially if it kept its analog signal on the air until 2009 as most stations did. Then, when the NTSC was shut off, the digital signal could have been moved to true channel 23. Two of the stations here in the S.F. Bay Area did this, so their signals are now really on the numbers they use (channels 7 and 36).
Actually, Chris, the technical term for what channel 23 did is "flash cut" from analog to digital, remaining on the same RF channel, but I'm not very familiar with the technique. Digital TV technology is very new to me, since I learned everything I know today about TV in the '60s and '70s -- when NTSC analog TV was still the standard of choice for U. S. and Canadian telecasting. I am familiar with such things as streaming video over the Internet (I sometimes watch the national evening news online if I happen to miss it on TV), but I have a lot to learn about digital television. Fortunately, there is a wealth of information on that very subject right here at VK (and elsewhere on the Internet), so you can be sure I'll be reading everything I can get my hands on regarding DTV and related subjects. I enjoyed watching NTSC TV but times have changed, so it's time to upgrade my knowledge for the DTV era. I also enjoyed working on NTSC television sets, but since everything now is solid state, surface-mounted components and so forth, not to mention no more CRTs, it is time to move on. I'm still getting used to the idea, for example, of my flat-screen TV being devoid of a kilovolt-level high-voltage system, as was used in NTSC sets; I still expect to see the hairs on my arms stand up when I walk past my set when it is on. Again, I am very glad and thankful that there is so very much good information here on ATSC digital TV, and, thanks to VK moderator Tim (Kamakiri), even a separate forum (Flat Panels and Digital Formats) in which to discuss this new technology. That forum is an idea whose time has come, and which brings Videokarma into the 21st century.
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  #20  
Old 01-13-2012, 01:19 PM
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Originally Posted by Jeffhs View Post
Actually, Chris, the technical term for what channel 23 did is "flash cut" from analog to digital, remaining on the same RF channel, but I'm not very familiar with the technique.
FCC records provide a glimpse as to how this was done (digital was on ch 59 before the transition):

Quote:
SECTION II - CURRENT STATUS
1.
Currently Assigned Channels:
a. NTSC Channel: 23
b. Post-Transition DTV Channel: 23
c. Pre-Transition DTV Channel (if different from Post-Transition channel.) 59
2.
Relevant FCC File No. for Post-Transition Authorization, if on file with Commission (or indicate "Not Yet Filed"):
FCC File No. BPCDT- 20070625ACA Not Yet Filed
3.
Current Construction Deadline: 02/17/2009
From the WVPX "Transition Status Report" filed 10/21/08

jr
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  #21  
Old 03-09-2012, 03:37 AM
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From 1936 until about 1985 the London area (UK) was served by a BBC TV station on Channel 1, vision 45.00MHz, sound 41.50MHz. Several million people received that transmitter.
John
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  #22  
Old 03-09-2012, 04:55 PM
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I guess if you didn't live in the U.S. during the second half of the 20th century you wouldn't wonder about channel 1. For generations those of us who did knew nothing but sets with dials that started at 2 .
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  #23  
Old 03-24-2012, 02:38 PM
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Channel 1 coverage could've been interesting if the Frequently Confused Commission had allowed 100KW visual 20KW aural at 1000' HAAT as they did so many low-band VHF TV's!

Also, the one station confirmed as operating on channel 1 never used the figure "1" in any of the material I've seen. They always put it as "Channel One".

Regarding Channel 1, there was talk at one time post-WWII to move TV to VHF-Hi and above. Channel 7 would've been the "new" channel 1. ABC-TV was supposedly so confident of that happening, that was supposedly why all their CP's were for channel 7! At least according to an ABC old timer I had talked with...
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  #24  
Old 03-26-2012, 03:02 PM
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In the pre-TV 1930s, hams had a frequency allocation in that general neighborhood...the old "5 meter" band...just a few mHz up from the present 6 meter allocations. Channel One was probably the most interference-prone of the VHF lowband channels with spring & summer "skip" being a real problem. Channel 2 wasn't a whole heck of a lot better...I can recall growing up in Western MN and attempting to get Channel 2 out of Minneapolis on a "skippy" day and getting Winnipeg instead. Sadly, TV DX like that is pretty much history.
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  #25  
Old 03-26-2012, 11:34 PM
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Quote:
Originally Posted by dewdude
I had read, in some really old television installers handbook, that Channel 1 was abandoned mostly due to extremely poor performance; picked up ignition noise from cars and such.
I thought channel 1 was re-allocated for EMERGENCY use but they didnt ever use it....

http://en.wikipedia.org/wiki/Channel...th_American_TV

Last edited by Dude111; 06-12-2012 at 07:40 PM.
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  #26  
Old 05-13-2012, 01:35 AM
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Interesting to hear the different stories on this. First off, AFAIK, Channel 1 did not become the 6-meter amateur band. Channel 1 was 44-50 MC (not a typo - MC instead of MHz before 1966), Channel 2 54-60, and the 6-meter band was (and still is) 50-54 (MC or MHz). This allowed for Channel 1 to be used anywhere, even if there were a channel 2 in the area.

The plan was for Channel 1 to share the 44-50 MC spectrum with land mobile radio. They had thought that only in larger cities would there be a demand for mobile radio (that quickly turned out to be wrong as every rural VFD and county sheriff wanted it) and Channel 1 could be used for "local" TV stations in smaller cities and towns (much like the "graveyard" AM radio channels, 1230, 1240, 1340, 1400, 1450 and 1490).

The plan was doomed from the start, as mobile radio would cause too much interference, and it was found that television networks would not sign up affiliates in small towns that overlapped stronger big-city affiliates and O&Os as they had been allowing with radio.
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  #27  
Old 05-13-2012, 01:41 AM
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Quote:
Originally Posted by electronjohn View Post
In the pre-TV 1930s, hams had a frequency allocation in that general neighborhood...the old "5 meter" band...just a few mHz up from the present 6 meter allocations. Channel One was probably the most interference-prone of the VHF lowband channels with spring & summer "skip" being a real problem. Channel 2 wasn't a whole heck of a lot better...I can recall growing up in Western MN and attempting to get Channel 2 out of Minneapolis on a "skippy" day and getting Winnipeg instead. Sadly, TV DX like that is pretty much history.
Winnipeg never had a channel 2, you were probably getting Vancouver! (Sporadic-E favors distances of about 1,000 miles).

TV DX by Es is still possible, though there are far fewer stations on channels 2 to 6 to DX (most lowband stations chose to spend their digital future on UHF or highband channels). The poor multipath tolerance of DTV also makes it more difficult for a DTV signal to be decoded when it is coming in by Es.
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  #28  
Old 08-22-2012, 02:57 AM
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Originally Posted by Jeffhs View Post
The short answer to this question, without going into a lot of history and details, is that the frequencies once known as television channel one in the U. S. were reassigned by the FCC in the late 1940s-early fifties, but not necessarily to land-mobile radio services. These frequencies, again without going into details, eventually were reassigned to the Amateur Radio Service as the six-meter amateur band.
Oh, c'mon, lets get into some very interesting details about Channel One.

Channel 1 was allocated at 44-50 MHz between 1937 and 1940. Visual and aural carrier frequencies within the channel fluctuated with changes in overall TV broadcast standards prior to the establishment of permanent standards by the National Television Systems Committee.

In 1940, the FCC reassigned 44–50 MHz to the FM broadcast band. Television's channel 1 frequency range was moved to 50–56 MHz (see table below). Experimental television stations in New York, Chicago, and Los Angeles were affected.[1]

Commercial TV allocations were made by the Federal Communications Commission (FCC) under the NTSC system on July 1, 1941. Channel 1 was located at 50-56 MHz, with visual carrier at 51.25 MHz and aural carrier at 55.75 MHz. At the same time, the spectrum from 42 to 50 MHz was allocated to FM radio. Several commercial and experimental television stations operated on the 50-56 MHz Channel 1 between 1941 and 1946, including one station, WNBT in New York, which had a full commercial operating license.

In the first postwar allocation in the spring of 1946, Channel 1 was moved back to 44–50 MHz, with visual at 45.25 MHz and aural at 49.75 MHz. FM was moved to its current 88-108 MHz band. But WNBT and all other existing stations were moved to other channels, because the final Channel 1 was reserved for low power community stations covering a limited area. While a handful of construction permits were issued for this final version of Channel 1, no station ever actually broadcast on it before it was removed from use in 1948.

There's MUCH more about channel one where this came from:
http://en.wikipedia.org/wiki/Channel...American_TV%29

Read it all and you'll understand!

Cliff
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  #29  
Old 08-23-2012, 05:57 PM
W3XWT W3XWT is offline
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Wikipedia

Cliff, my good friend,

I found some possible errors with the Wikipedia article on channel 1... or, "Channel One" as WNBT always called it, IIRC.

If W9XZV was the first "all-electric TV station", were the others steam powered? Perhaps using disused locomotives as a joke promo I saw years ago out of the U.K.?

Also, K2XBS was really KS2XBS and KS2XBR, the latter of which was still on-air into the 1970's on channel 38 testing systems later used in Zenith's OTA and cable scrambling systems. I'm sure our friend Wayne ("the flicker kicker") can provide more info on those stations.

Ahhh Zenith... where the parts went in before the name went on!
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  #30  
Old 08-23-2012, 11:49 PM
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You know what's funny, I have a few modern TV's, even HDTVs, that have the ability to tune to channel 1.. Even my Panasonic VCR can do it.

Not sure why if nothing is going to be there.

I also once had a cable box that had a channel 1, which showed some PBS channel, but none of the TV's with channel 1 capabilities, showed anything on it without the box.
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