Hi Counters go back at least into the early 1950’s. I started out with fully vacuum tube (except for diodes) counters obtained as surplus in the mid 1960’s. They used some odd gas filled triodes. Everything in them could have been on the market in 1947. They were not a common thing until the late 50’s.
Prior to that (WWII era) the standard approach was to use a heterodyne frequency meter. They could be quite complex. I once passed up a “deal” on one that spread out over several rack cabinets. The idea was that you produced a beat against this or that and then beat it again against something else. Ultimately a meter or scope showed you the phase offset. The heterodyne approach lived on in the era of the counter using a synthesizer as the reference. The beat note went into an analog meter based audio frequency meter. It allowed you do do cute things like servo to a target when grinding or plating something to frequency. One key thing to keep in mind: in the 1930’s it is rare to find a frequency spec that is not stated in percent (with some zeros involved). A tight spec was in the 20 ppm (or 0.002% ) range. The idea of a heated crystal as a reference was a “national standards” sort of thing in 1935. The crystal industry as we know it today really only dates back to 1939. Before that the number of producers and the volume produced was *very* small. Bob > On Feb 12, 2017, at 1:08 AM, Scott Stobbe <scott.j.sto...@gmail.com> wrote: > > I was inspired recently coming across a Lampkin 105 frequency meter, as to > how frequency measurement was done before counters. > > Certainly zero-beating a dial calibrated oscillator, would be one approach. > > Is there a standout methodology or instrument predating counters? > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
