RF Cafe Software
About RF Cafe
1996 - 2022
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...
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You know by now if you have visited RF Cafe a few times that I like to collect and restore vintage electronics and mechanical items that can be put to use - as opposed to just accumulating stuff and never using it for anything (although, admittedly, I do a bit of that as well). Since I don't do it for the collector's value, most items, if they are not already in good condition, get reworked until they look as new as possible - and work. Some 'experts' would admonish me to leave the items with their original paint, varnish, metal and wood parts, etc., and never do anything that would destroy its authenticity. If I ever happen to acquire a Rembrandt or a Stradivarius, I'll be sure to heed the advice.
Part of RF Cafe's charter is to be a resource for people of like mind that are looking for historical information, restored examples, repair and renovation tips, etc., on vintage (aka retro) gear. Anywho [sic], for $20 on eBay I bought a like-new General Electric model 7-4305C roll-down (aka 'flip-number') number clock-radio, date code 2051, made in Singapore. It was accurately listed as being in like-new condition, but with the display light not working. I replaced the neon bulb with a spare I had in my box of stuff and, voila, now I can read the time numerals at night!
My motivation was to re-acquire the type of clock, radio, and alarm that was around when I was a kid, in the pre-electronic display era. A very similar model annoyed me awake each morning so that there would be no excuse for not arising in time to catch the school bus (my opinion of school in those days was similar to that of Calvin).
At some point I will post a more complete series of photos of the mechanical and electrical workings of the clock-radio.
June 11, 2015 Update: See info on the AC synchronous motor used for the clock display.
Posted December 10, 2014