wowww OC71... it is probably the oldest one i've ever held in my hands.
not sure if i still have one but i remember black painted glass ampulas
with three long wires and a little red dot. paint would peel too easily...

 

OC71's were fairly expensive (actually VERY! expensive), but you could buy cheaper transistors, simply marked 'red spot' or 'white spot', I seem to remember one was an RF transistor, the other an audio transistor, but I can't remember which was which?.

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I got my 1st transistor radio in about 1958 and it had transistors in metal cases with the top pinched then welded shut.
Then I got my 1st job at Philips and saw lots of cool new stuff like the 1st cassette player to play music instead of speech, and the LED "with its junction glowing red-hot". :lol:

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Uncle $crooge

 

Nigel, the transistor was discovered (not really invented) in 1948. I remember trying to make my own out of a germanium 1N34 but since I didn't know what I was doing, it didn't work. I was working for GE in 1956 and GE was making transistors then. So my transistors are 49 years old!

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My 1st radio was made by GE. :lol:

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Uncle $crooge

 

I have some CK722s. I built a regen AM receiver out of one in about 1958 or '59.

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Ron

 

I remember reading about circuits using CK722s in magazines.
Look what I found. If you look closely you will see that the supply voltage is the wrong polarity!

Attached Images

philips_transistor_amp-1955.png (186.7 KB, 207 views)

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Uncle $crooge

 

use a very-fast-switching transistor to make the inverter. i'm afraid though, that it would fall far short of your 100MHz...

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