View Full Version : Channel 1


Tube TV
10-09-2007, 11:40 PM
what year was the last year for channel 1 ?
1947 or 48 .

Adam
10-10-2007, 12:37 AM
I think it was '47.

Tube TV
10-10-2007, 01:58 AM
The 1947 RCA sets still had channel 1 . But maybe they had all the parts ready for sets with channel 1 , and ran them through till 48 . the 1948s started a channel 2 . I would think 1947 was the end for channel 1 .
Does anyone know what was transmitted on it after it was not used for television ?

wa2ise
10-10-2007, 01:46 PM
Does anyone know what was transmitted on it after it was not used for television ?

No TV station was ever on channel 1, as it had the old 45MHz FM band still alive until 1950. After that sunsetted, it became a band used by state police and such.

ChrisW6ATV
10-10-2007, 03:07 PM
Later, cordless phones were on that frequency range (46/49 MHz ones).

stromberg6
10-10-2007, 06:40 PM
30 to 50 mHz became a "public service" band, for use by police, fire, business, etc. 50 to 54 became the 6 meter Amateur band.

tubesrule
10-11-2007, 07:31 AM
http://members.aol.com/jeff560/tvch1.html

kx250rider
10-11-2007, 12:51 PM
All the '48 RCAs had it, but maybe that was just due to overstock of tuners with Ch 1.

I thought W6XAO (Don Lee) broadcast on Ch 1 during the experimental days, and W6XYZ (now KTLA) was on Ch 5 to be spread at opposite ends of the band in Los Angeles... I don't remember where I heard or read that, but it could be wrong.

Charles

wa2ise
10-11-2007, 02:58 PM
If you have a vintage TV set with a Channel 1, you could do two things to feed it a Channel 1.

First method: Modify a TV modulator from a VCR. Depending on how it makes its channel 3 or 4, add extra capacitence to the oscillator it uses to make the video carrier. You don't need to mess with the sound carrier, as most of these things FM modulate a 4.5MHz carrier and then add it to the video to then be modulated onto the TV channel. You want to move that video modulator frequency to 45.25MHz. And the sound will appear at 49.75MHz. This is opposite of what you see on modern TV set IF strips BTW.

2nd method: Use a UHF tuner from an older TV set. But you need to shift the local oscillator from 45Mhz above the desired TV channel, to 45Mhz below the desired channel. Else the TV sound will be on the wrong side of the video carrier. But odds are that the image rejection of these things is so poor that a local strong UHF TV channel will make it thru fine. Tune it about 15 channels higher than the desired channel, like channel 46 for channel 31. Or channel 65 for 50. Or 83 for 68.

Steve McVoy
10-11-2007, 04:28 PM
A bunch of stations transmitted on the approximate frequency of channel 1 before the war. I think what WA2ISE means is that no station broadcast on that frequency after it was allocated as channel 1 by the FCC.

kbmuri
10-11-2007, 06:12 PM
The Capehart 661P is said to have either a 13-channel tuner or a 12-channel tuner, according to my service manual (channel 1 was deleted mid-production). It's listed as a 1947 model. I meant to look at the ETF last spring to see if Steve McVoy's is a 13-channel or a 12, but forgot. Steve? Any documentation on its manufacture date?

ChrisW6ATV
10-12-2007, 02:52 AM
Another method to generate Channel 1 is to get a programmable commercial modulator such as an Olson Technology OTM-3000 (I think that is what I have). They are programmable in 0.25-MHz steps down to maybe as low as 40 MHz, so Channel 1 (45.25 video/49.75 MHz audio) would be possible.

Steve McVoy
10-12-2007, 11:03 AM
It appears from the photo I have that the 661-P has a 12 channel continuous tuner.

Randy Bassham
10-12-2007, 12:58 PM
For what it's worth up until I retired last April I maintained 4 transmitters on 42 mhz putting out 1500 watts for the Missouri HP. Lo Band has the greatest coverage with the lowest amount of infrastructure available, but it's not hi-tech and is subject to a lot of interference from other RF generators (computers) in the car so the powers that be are itching to get rid of it. Whatever takes its place will have lots of infrastructure between the base and mobile. That really worked out well during Katrina....