In my collection of stuff, I happen to have a really old piece of radio equipment. According to the data-plate, it is a SG-44 Signal Generator made by Winslow Tele-Tronics, INC. I tried looking up the company, and the best that I could find is that it was established in New Jersey in 1970, and that they built a lot of equipment for the US Army and Navy. However, there is some ambiguity, since some of the telegraph keys I found online, supposedly from this company, pre-date the creation of the company itself.
So the company either existed elsewhere before coming to N.J., or the owners of the equipment selling them on Ebay or online have the wrong manufacturing dates. Either way, this unit is stamped with the plant in New Jersey, so we can safely assume it was made after 1970. What is curious about that, though, is it lists everything in Mega-Cycles, instead of Mega-Hertz.
The reason this is odd to me, is that the international standards changed to use MHz (Mega-Hertz) instead of MC/s (Mega-Cycles/Second) in 1968. Further, the term MHz was in use since 1965. So I’m not sure why this unit, built in the 1970’s would still use the old definition. I can only guess that the production plans to build this unit were prior to 1968, and they continued to produce this unit into the 1970’s. Another theory is that the US Navy, for whom this is supposedly built, didn’t jump on the MHz bandwagon fast enough.
For those who don’t know, it is simply a name change from MC/s to MHz. The conversion is direct and linear. 1000 MC/s is equal to 1000 MHz. Although I did find some funny charts where they tried to make it look complicated while still saying that same thing.
In any event, this unit can generate a signal from 10 MHz up to 420 MHz. For HAM radio operators, that covers from just under the 20 Meter band up through the very start of the 70 CM band. Of course, the purpose of a signal generator is to generate a set signal. In this case it is used to generate a 400 Hz or 1000 Hz signal. That signal is usually used for testing purposes to ensure your equipment is calibrated and working properly. For your reference, middle C on a piano is 261.6 Hz (the 40th key on the piano), so a 400 Hz signal is the 47th key on the piano, a G, while the 1000 Hz signal is the 63rd key, a B. Of course they are not exact matches, but close enough, just a little sharp.
Now the question becomes, what do I do with it? I suppose now I need to figure out if it works, and I can’t find any manuals online for it. Hmmm…. more to think on, I suppose.
Linux – keep it simple.