Crazy thought.Could you just force a DC offset into the EFC assuming the internal varicap is not out of range. It would be simply adding a resistor to pull up or down to see if you can get a bit of pull and allow the dac to move back in range a bit. Its a band aid. I know its sort of crazy. But ripping the oven apart really is no fun at all. Regards Paul WB8TSL
On Mon, Mar 5, 2018 at 11:21 AM, Joe Hobart <n...@npgcable.com> wrote: > > Thank you, Hal, for these links and to others for your comments. > > Setting the oven temperature on a turning point appears tedious. Perhaps > there > is enough range in the frequency adjustment to put the oscillator back on > frequency - or close enough for the EFC to be effective. If not, I may > have to > adjust the temperature, but time is limited. > > Some measurements with the EFC disconnected and a calibrated frequency > counter: > > 9999.815 KHz at Z3801A turn on > > 9999.9984 KHz highest frequency seen (temperature overshoot) > > 9999.9947 KHz approximate final frequency > > The EFC does have wide range; it can almost pull the 5.3 Hz offset onto > frequency. > > Thanks again, > Joe, W7LUX > > > > Does the oscillator have an adjustment? If so, is this somewhat > accessible > > without destroying the assembly? Are there pictures of the oscillator > > assembly? > > https://www.realhamradio.com/GPS-oven-journey.htm > > https://www.realhamradio.com/z3801a-turning-point.htm > > _______________________________________________ > 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.