[time-nuts] And you thought you were old
horsts at iinet.net.au
Tue Apr 20 14:52:29 UTC 2010
I still have an original booklet from raytheon : how to build a 1 transistor radio with a CK722.
However, my very first transistor first transistor was an OC70 from Valvo (German Philips). I bought it about 1956 ,I was 13 years old then in Stuttgart Germany.
It cost me 10.20 German Marks. A substancial sum then. I soldered the
transistor in to a socket , so the leads would not break off.
I build many different projects with it then.
Now when I see one of the old black Philips glass encapulated
transistors, I get quite nostalgic.
But this days one hardly looks at a modern transisitor anymore.
On 21/04/2010 12:19 AM, Mike Feher wrote:
> In fact, one of the first CK-722s that I took apart did have a smaller
> hearing aid type transistor inside. Later CK-722s were of course built as
> CK-722s and even later they were in black but somewhat clear epoxy cases. -
> 73 - Mike
> Mike B. Feher, N4FS
> 89 Arnold Blvd.
> Howell, NJ, 07731
> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
> Behalf Of J. Forster
> Sent: Tuesday, April 20, 2010 9:57 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] And you thought you were old
> Do you know the story of the CK722?
> In the 1950s, Raytheon was making tiny transistors for hearing aids to
> replace the pre-WW II subminiature tubes.
> Aside: Those tubes, developed by Norm Krim, were ruggedized and used in
> the WW II Proximity Fuzes, one of THE big inventions of WW II.
> Anyway, Raytheon was making piles of these tiny transistors, but many were
> not making hearing aid specs. Norm got the idea of packaging them to sell
> to hams to learn about transistors. If you open up one of the blue ones,
> there is another tiny case inside which is the real transistor.
> BTW, Norm is still alive and well in his 90s.
Anyone remember the CK722 transistor? As I remember they were about $7.50,
>> considerable sum.
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