Posted to sci.electronics.design,alt.binaries.schematics.electronic,sci.electronics.basics
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NPN Transistor Question
Michael Black wrote:
On Mon, 8 Jun 2015, John Larkin wrote:
On 8 Jun 2015 13:07:58 -0700, Winfield Hill
wrote:
John Larkin wrote...
Jim Thompson wrote:
;-) CK722 anyone ?:-}
https://dl.dropboxusercontent.com/u/...s/Ck722-0A.JPG
https://dl.dropboxusercontent.com/u/...s/Ck722-2A.JPG
Used to cost a week's allowance.
Here's the 1952 datasheet, Raytheon,
in Newton, MA, my old stomping ground.
https://www.dropbox.com/s/gtly97ud6j...952_1st-pg.gif
Beta is 12 typ, no Ft specified.
My first job interview, I told the guy that I preferred tubes to
transistors, because transistors were too easy to blow up. He said
"that won't do" and ended the interview.
There's the classic QST article in the mid-fifties, an introduction to
transistors. And it comes right out and says "they can't amount to much,
if nothing else, they don't work at high frequencies".
I'm paraphrasing, but I heard about the article long before I read it.
And it really did say something along those lines.
I'm finding it quite amazing now to read about multiband transistor
portables that were out in the late fifties, I assumed that sort of
thing didn't arrive till the sixties. A lot of those early transistor
shortwave radios were junk, but there was the National HRO-500 in 1964
that's considered an expensive classic.
* AS i vaguely remember, the bandwidth-extending trick (borrowed from
tube circuits) of neutralization was used.
Michael
Next guy, I said the same thing. He laughed and hired me, and I
designed about $200e6 worth of stuff for him. He also told me that
some day a transistor inside an IC would cost ONE CENT. I thought he
was crazy.
--
John Larkin Highland Technology, Inc
picosecond timing precision measurement
jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com
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