View Full Version : Channel 1


John Hafer
01-19-2010, 09:24 AM
I remember years ago cleaning out a garage for a friend of mine and on the shelf was an old B&W television in a wooden case. It had a tiny tube screen but what caught my eye was that the channel changer stated on ch. 1 and went to ch. 13.

Anyone else ever seen an old television with ch. 1 on the tuner? Anyone know when sets dropped the ch. 1 and started with ch.2?

Adam
01-19-2010, 10:00 AM
I think 1947 was the last year for channel 1. I have 3 sets with channel 1, the RCA 721ts, 630ts, and the DuMont RA-103. (only the 721 is restored and working)

zenithfan1
01-19-2010, 10:05 AM
Yep, if you find a set with channel one, grab it. Here is a good link to explain why they got rid of it. It looks like Kenosha had a channel 1 at the time too. Kinda cool.
http://www.anarc.org/wtfda/channel1.htm

Zenith26kc20
01-19-2010, 12:04 PM
In my room of the hungry, waiting to be restored, there is a Motorola TS-4J with channel one. It's in very poor condition, no knobs, metal ballast and no back.
I don't think New Orleans ever had Channel one.

jr_tech
01-19-2010, 12:24 PM
Some of the early 7" Hallicraters sets have ch 1.... Here is one on the 'Bay:

http://cgi.ebay.com/Vintage-40s-HALLICRAFTERS-7-TV-Television-Model-505_W0QQitemZ190365688161QQcmdZViewItemQQptZVintag e_Electronics_R2?hash=item2c52ade161

There is also a "fine tune" knob at the right end of the row of buttons which looks like another channel button. This has confused collectors that have purchased 13 button sets based on a poor photo, thinking that they had ch 1... nope, you need "14 buttons" to get ch 1 on this model.

not affiliated,
jr

Adam
01-19-2010, 01:20 PM
I've never seen one of those Motorolas with channel 1 before, all mine start at ch2.

bandersen
01-19-2010, 01:39 PM
I've never seen one of those Motorolas with channel 1 before, all mine start at ch2.

Here's the control area from my blonde VT71.
http://www.bobandersen.com/images/VT71%20blonde/vt-71%20blonde%20decals.jpg

wa2ise
01-19-2010, 03:32 PM
For that TV with a channel 1: Some time ago I posted (http://www.videokarma.org/showthread.php?t=220321) about modifying some TV modulators (the sort usually found in older VCRs) to channels 2, 5 or 6. By changing the SAW resonator to a crystal. But for the old channel 1:

Had some trouble moving a TV modulator to operate on the old channel 1 frequency, 44.25 picture carrier. From a huge stash of old police radio xtals the closest frequencies I could find was 45.3 for channel 1 (only 50KHz off).

Before, the modulator osc circuit wouldn't run at frequencies this low, but I increased the loading caps (caps from the xtal to ground). From about 4pF to 8pF. Now it runs. Seems that lower frequency xtals need bigger loading caps. Likely to yield a similar reactance at the new freq like that with the old cap at the old freq. Those of you who have experience in xtal osc circuits would recognize this, probably better than I would. Some hard core engineering info: http://www.analogzone.com/hft_0102.pdf
Figs 5 and 6 show that larger caps shift the osc freq range down. Crudely speaking, this would make a circuit that worked at a higher xtal frequency work at a lower freq xtal.
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7"estatdef
01-23-2010, 07:28 PM
The Motorola VT-71 had a lot of different versions. I think that only the earlier versions had channel 1. Like A though G or so. It's important to know which one you have to get the right diagram. Good news the knobs and mask are available.
Terry

Dude111
01-30-2010, 08:56 PM
Yep, if you find a set with channel one, grab it. Here is a good link to explain why they got rid of it. It looks like Kenosha had a channel 1 at the time too. Kinda cool.
http://www.anarc.org/wtfda/channel1.htmQuite an interesting link,thank you :)