Thread: Drake SSR-1
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Old 6th Sep 2017, 6:11 pm   #4
John KC0G
Hexode
 
Join Date: Mar 2009
Location: Minneapolis, Minnesota, USA.
Posts: 275
Default Re: Drake SSR-1

IMHO, definitely interesting stuff!

The web page by PA2OHH is interesting reading. I did not know that the circuitry of the XCR-30 Mk II and SSR-1 had so much in common. Perhaps one should not be surprised. Trevor Wadley had made the design of the XCR-30 Mk II as simple as it needed to be to do the job. The early version of the XCR-30 Mk II used discrete transistors in the audio p.a. stage. The later version, like the SSR-1, used an i.c. amplifier.

The SSR-1 had a poor reputation when it was on the market. The comments in various editions of the World Radio and TV Handbook were far from complimentary. PA2OHH makes the reasons clear, not least of which was that it was a portable design in a base station's clothing to be used as a base station.

There was a further stage of development. Lowe with the SRX-30D, and Century with the 21D models offered a digital frequency display. The Century 21D manual be found online. The display used two long since obsolete MSM5525RS counter chips, one for the MHz digits and the other for the kHz digits. The arrangement was quite clever. The 21D also used SL1641 mixers. I assume, but do not know, that the SRX-30D was very similar to the 21D

73 John
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