old question: why isn't there a Channel 1?
 

Answer:
There was a Channel One once upon a time--in 1945, to be precise, when the Federal Communications Commission first allocated broadcast television frequencies.

Later, however, the FCC repented its generosity and decided that TV was hogging too much of the broadcast spectrum. (Each TV channel requires a bandwidth 600 times as wide as an individual radio station does.) So the Channel One band (44 to 50 MHz) was reassigned for use by people with mobile radios.

Add that to your bag of useless trivia! :D

Old news to me....been in my bag of "useless trivia" for years now.

:rolleyes: @ E-M
Thanks for that info, Celt!

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. If anyone here is a radio amateur operating six meters, and has a TV that still tunes channel 1 (many late-'40s Hallicrafters sets and possibly others of that era did), it shouldn't be too difficult to retune that channel's oscillator and antenna circuits to 50-54 MHz.

BTW, six-meter operation was probably not very prevalent in areas with a channel 2 TV station, due to the risk of interfering with reception of that station. The reason is that the low end of the frequency range of channel 2 is 54 MHz -- right at the top of the hams' 6-meter band. While most amateurs did not operate anywhere near that close to the edge of the band, some did, and therein lies the problem. If an amateur were operating, for example, on 53.8 MHz, lived in an area with a channel 2 TV station, and his neighbor was trying to watch a program on that channel, the latter would not be pleased when "WB8XYZ calling WA8QRP, over" blasted through his TV speaker (along with interference to the picture), right over top of the program he was trying to watch.

I bet there was quite a bit of trouble like that in channel 2 areas in the early days of TV, immediately after the 6-meter band was opened to amateurs. I don't think there was much 6-meter activity in cities with channel 2 television stations for just that reason. This applies, of course, to television's beginnings in the late 1940s and very early fifties, when everything was on 12 channels, broadcast in monochrome and analog; NTSC color and UHF hadn't yet been thought of and the first TV systems in the U. S. were, of course, analog. The arrival of UHF in the late 1950s-'60s brought with it even more problems, not the least of which were weaker signals and a severe lack of sets that could receive the then-new UHF stations. Since most people living in areas with at least one UHF station still had VHF-only sets with UHF converters in those days, and the UHF stations themselves of that time weren't the high-power monsters they became by the '70s, the potential for interference was greater than before, not necessarily from 6-meter amateur signals but from hams' transmissions in other bands as well. Since UHF converters downconverted incoming UHF TV signals to an unused VHF channel, usually 5 or 6, a strong amateur signal appearing on either of these channels could cause real problems. Channel 5 is 76-82 MHz, six is 82-88 MHz, of course, but a very strong signal, amateur or otherwise, can blast its way past the tuner regardless of the channel's nominal frequency.

In the early 1970s, I lived in a Cleveland suburb which had an FM station on 92.3 MHz. I was living just one street over from that station's tower, and that station created very serious interference problems, not the least of which was to my TV, a 1964 Silvertone roundie, on which I could receive that station perfectly well (!) on channel 6. The problem was caused by the extreme signal strength in the area where I lived; it was just blasting its way through the set, with no regard for the tuned circuits in the tuner or anything else.

Hmmm. :scratch2: I wonder if DTV is prone to the same kind of interference problems we had to tolerate in the NTSC analog era.

Your recieving FM on that Silvertone in close proximity to the station sounds to me like your set picking up a harmonic. All transmitters produce some amount of harmonics (I don't fully understand harmonics, but I believe that they are multiples of the desired frequency) which the owners of the transmitters go to great lengths to suppress, but at close range to a powerful transmitter it is not all that difficult to imagine that the harmonics were strong enough to tune in clearly.

Yup...at times harmonics can indeed be annoying... :)

http://farm4.staticflickr.com/3532/3...e25532870c.jpg

Yes

What I've always wondered about is overlap with the old FM band. It seems that in 46 and 47 they were making both radios with the old 42-50MC FM band, and TVs with CH1.

When I was a kid, I thought that there was no Channel 1 because all the TV stations would have fought to get that one. It wasn't until 1979 that I first saw a TV that had it.

I have never found out for sure if any stations ever actually transmitted on Channel 1 in the post-war period. There are lists of TV stations from about 1946 that do include several on Channel 1 around the USA.

At least one of the agile modulators I have seen (often used by us collectors to recreate NTSC signals for our collections) has the ability to operate on Channel 1. Now that I have a working TV with it (described here), I am going to set up an in-house Channel 1 signal.

My 721ts on ch1 using a B-T AM40-450 modulator:

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.

My grandfather explained it to me this way as well. He said it was always an extremely noisy channnel, and after it was decided to not use it for TV, it was reassigned.

That's pretty much how I remember it as well.

That makes sense in fact; I know in my NTSC-watching days (specifically, with indoor antennas), Channel 2 was always the worst-looking and hardest to receive clearly. Channels 4 and 5 were better but often not great, and Channels 7, 9, and 11 almost always were easy to receive well.

One of the nice side benefits to the switch to ATSC is that most stations moved to UHF. Now if they would only get rid of the silly fake "channel" numbers left over from the old days.

Here's how I remember the NTSC days....back when I still had a working antenna on the roof, living here 40 miles or so from DC.

"Local" channels 4 and 5 came in ok. 7 and 9 were always the easiest and clearest. The UHF performance was horrible. The only analog uhf channel I got was. 53...only because I lived 5 miles from the transmitter. In fact, at night, I can see its blinking red light just over the tree tops.

Baltimore channels were iffy. They were all fuzzy, but 2 came in better than 11 or 13, Baltimore UHFs were impossible.

Mind you, I live amongst trees, in a slight valley, without a very good antenna or rotor.

When things went ATSC, well..back when I had an OTA tuner, everything was UHF, and I couldn't get anything. I had better luck getting one or two locals in digital with an indoor antenna.

Lower frequencies travel "farther" due to the fact they follow the curve of the earth slightly...higher frequencies are more line of sight. Higher frequencies are less sensitive to interference as lower frequencies. In TV, this simply means a VHF signal is going to travel farther than UHF. UHF will have less interference than VHF...but more noise. UHF transmitters usually used quite a bit more power because of that.

The official switch to all digital....I honestly don't know why many stations stayed UHF. The virtual channels are simply because they can, and its what we all grew up with. Its like I'm used to refferring to WTTG as channel 5...not 35,36, whatever its on these days. I'm sure they mostly wanted to avoid confusion to people who, for the most part, grew up with those channel numbers.

I hear ya. The broadcasters did not want to "give up" their incumbent channel listings even though in some markets, they marketed (and still do) their primary cable channel listings. Plus there was the baggage of UHF being "inferior". PSIP remapping has IMHO caused more issues than solved by the silly remapping scheme.