I was in missile class in the Air Force in 1963 and the lab and course was
entirely in tubes even though the missile was entirely in transistors. The
adaptation was very short (minutes, maybe and hour) and said that
transistors worked like tubes except at lower voltages and power levels.
That was all there was to transistors !!! Not bad really for a class that
hadn't been rewritten yet (and that may have been all the instructor knew at
that time).
73, de Jim KG0KP
----- Original Message -----
From: "Bob Nielsen" <nielsen@oz.net>
To: <towertalk@contesting.com>
Sent: Tuesday, November 16, 2004 12:10 PM
Subject: Re: [TowerTalk] Vacuum tube 100 years old today
> On Tue, Nov 16, 2004 at 11:28:11AM -0500, Tom Rauch wrote:
> > On Nov. 16, 1904 Fleming patented the Fleming valve. The
> > vacuum tube is 100 years old today (exactly 46 years to the
> > day older than I am).
> >
> > I was an electrical engineering student in the late 60's.
> > The electronics lab stock room was full of tubes and
> > sockets, and our benches had 300 volt power supplies. About
> > 50% of our inventory and study was tube related. I built a
> > complete 500 watt HF station, receiver and transmitter, from
> > stock room parts in my spare time. Every component necessary
> > was in the stock room. From a textbook I still use,
> > "Electronic Amplifier Circuits" McGraw-Hill Electrical
> > Engineering Series 1961, comes the following quote:
> >
> > "For many applications a relative newcomer, the transistor,
> > is replacing vacuum tube types because of the greater
> > inherent reliability, lower power consumption, and smaller
> > size. However, the complete replacement of the tube by the
> > transistor does not seem likely, for the latter has
> > shortcomings at high temperatures and high radiation
> > intensities and in the production of high power at high
> > frequencies. "
> >
> > About ten years later I received a call asking if I wanted
> > any of those old tubes, tube related books, or HV bench
> > power supplies before they hit the dumpster.
> >
>
> I was taking a senior physics class in electronics at UCLA in 1962 and
> we spent some time studying vacuum tube circuits. The professor was
> asked if we were going to learn anything about transistors and replied
> that he had never studied them himself, since he felt that they were a
> fad which wouldn't last.
>
> 73,
> Bob N7XY
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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