I have a General Radio Type CAG-60098-A Precision Wave Meter made for Navy Department - Bureau of Ships according to the nameplate. According to Wikipedia that would date it between 1940 (when bureau of ships was created) and 1966 (when abolished). It has an inductor in sort of a "hockey puck" labeled 16-50 kc that plugs into a socket on the front panel. Inside is a very nicely made variable capacitor with a vernier drive. It has been a while since I had it apart, but there is a diode in series with the meter and not much else as I recall. The meter scale is 0-200 (microamp?) and the capacitor scale is 0-75 with no other marking. I have no manual, but I assume there were other inductors for different frequency ranges with a calibration chart to interpret the 0-75 reading. It must have been made to test transmitters by tuning for peak reading on the meter and determining the frequency from the dial reading.
a different Alan (KE7AXC) On Sun, Feb 12, 2017 at 5:47 PM, Alan Melia <[email protected]> wrote: > Hi Dan yes that is 5e-6 about all an unstabilised (temp) AT could hold for > any period. I guess there were no WWV or MSF signals around then. When a > good source was available off-air it was possible to do better than that. > In service it was probably "dont waste time trying to better the minimum > requirement. The transmitter you are looking for wont be that accurate or > stable" > > In 1960s I saw several BC-221s in the racks at the Rugby LF and HF > stations acting as standby frequency sources (VFO) for rapidly running up a > transmitter on an unusual frequency (not a normal route) for which they did > not have a crystal available. > > Alan > G3NYK > ----- Original Message ----- From: "Dan Rae" <[email protected]> > To: "Discussion of precise time and frequency measurement" < > [email protected]> > Sent: Sunday, February 12, 2017 11:11 PM > Subject: Re: [time-nuts] Vintage Frequency Measurement > > > To put BC-221 things in perspective, the 1 Mc/s reference crystal was >> adjusted, according to the manual, to within 5 c/s... >> >> Things have come a ways since! >> >> Dan >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to https://www.febo.com/cgi-bin/m >> ailman/listinfo/time-nuts >> and follow the instructions there. >> > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/m > ailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
