From: Philip Nasadowski
Subject: Re: Digital divide by ten, 1949 style
Date: Sun, 15 Sep 2002 23:04:11 -0400
Organization: Biker/metalhead from hell!!!
References: <3D84D4B3.50B511EF@webaccess.net> <3D850A3C.31381AD5@webaccess.net> <3D852DB5.2AEB8909@webaccess.net>
NNTP-Posting-Date: 16 Sep 2002 03:07:28 GMT
X-Harley: '99 FXDWG
User-Agent: MT-NewsWatcher/3.1 (PPC)
In article <3D852DB5.2AEB8909@webaccess.net>,
Chuck Simmons wrote:
> I had 10 or so single output tube 40KW linears that were a horror
> story, however. When the suckers caught fire it took a couple of days to
> get them back on line. They seemed to catch on fire a lot.
Hey, were they GE units? Given the firey history of some early GE
rectifier electric locomotives, I wonder how well GE really was at power
> OK. I didn't dig into many tuners. It seems to me the common turret
> tuner had two tubes.
Yes. Turrets normally had a dual diode RF amp (cascode), and a
triode/pentode for local oscilator and mixer. Typical of switchtypes in
the 50's, too. Some early switch and continuous types had bizzare
setups - multiple triodes, multiple pentodes, or weird things.
Some TV makers sourced out the tunner to another firm that did tunners.
Actually, a lot did. The big guys made their own, though. I used to
have a Zenith with a VHF/UHF type that was interesting, the UHF section
was die cast metal and had belts and pullies and all.
Turret and switch types eventually dominated because they worked, and
didn't suck like the continuous types did. Halicrafters had the
pushbutton tunner, but that was an exception. The more recent
'pushbutton' types in the 70's were varacator (or, Sylvania's were), and
now they use a chip to do some magic thing...
> I never looked at the earlier continuous tuning
> tuners that didn't last long.
The Mallory inductunner used in DuMonts was the only memorable unit. A
royal pain to use, at least the one in my Dumont RA-103 is....
> I would bet some money that turret tuners hit the market by 1950.
Philco had them around 47, I think. Early ones, you had only 6
positionsa and had to load in strips for what channels you wanted.
later ones gave you all 12 channels. Turrets are beautiful until the
contacts get dirty, and some idiot sprays contact cleaner into them,
which makes them worse. Then the cycle repeats. The end result is you
have to totally take apart and wash the unit out. Then they work great.
> I first saw a TV set in 1949. There were no TV
> shows. We watched the test pattern the brand new station was sending
> out. :-;
Hehehe. The good old Indian Head test pattern?
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