Monday, August 24, 2015

A Trip Down Memory Lane -- N6QW's first experiece with Solid State Devices

Case Zero -- How it Started

 
On August 23rd, 2015 I had cause to do an Internet Search on one of the most popular electronics magazines that started in October 1954. Oddly enough it was called Popular Electronics. In that issue I spotted an advertisement for one of the very early transistors that was available to electronic enthusiasts. Enter the Raytheon CK722 and you can see a snip of the ad below. Actually I had been using a CK722 prior to this ad --I must have been about 11 or 12 years old at the time and my use was as an audio amplifier for one of my crystal sets. Here you see the ad for building an electronic timer. Imagine what you could do with a solid state timer back in 1954.
 
Keep in mind the scientists at Bell Labs had invented the transistor a scant six years earlier. From a lab to the consumer in such a short period of time was simply amazing in 1950! Think about it -- there had to be a wholesale development of manufacturing techniques to mass produce transistors. Building one in a lab is a huge task, whereas building thousands of within spec transistors on a line is a whole different problem.
 
Raytheon manufactured a line of "pencil type" and sub-miniature vacuum tubes many which started with a CK designation like the CK7588. I suspect the CK722 nomenclature was simply a carry over from the vacuum tube part numbering system.
 
The CK722 came in a cool blue case with a red dot on the side which designated the collector as the three leads were inline. It was a PNP device so biasing and grounds were always a bit tricky --- the collector goes to ground!
 
I am pondering if when the CK722 hit the streets that there were those same "experts as we see today" who said --- "Well those will never work in homebrew radios, the phase noise is terrible and nothing lights up and glows". Very likely if there were email reflectors in 1954 those "experts" would proclaim "Don't use the CK722 because I heard the specs are no good -- the Ft is only 2 MHz and the phase noise is awful and they are PNP devices and on and on."
 
Well some of us simply ignored those naysayers and enjoyed this wonderful new technology! Nothing much has changed since 1954 --we still have those who only look to find fault with any new technology. One only needs to tune in to the chatter from today's naysayers who essentially have only looked at the spec sheets and state the Si5351 is unsuitable for use in our beloved ham rigs. Too bad they never have built anything but only parrot what they have heard.
 
Pete N6QW
 


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