Re: CM11A hangup: Any better products?

[ddl@danlan.*com (Dan Lanciani)]

In article <AQ8Pe.410$MN5.261@xxxxxxxxxxxxxxxxxxxxxxxxxx>, notthisjoergsch@xxxxxxxxxxxxxxxxxxxxx (Joerg) writes:

| This looks way different than mine. I have to look for the schematic
| tomorrow. If there were no crystal or resonator how would it ever be
| able to keep time? Mine holds to within a few minutes a year and temps
| range from 65F to 95F.

The CM11a does employ a resonator for the PIC's clock, but it uses a
separate free-running LC oscillator to generate the 120kHz carrier.  (That's
the oscillator in the schematic.) The TM751 and the current RR501 generate
the 120kHz carrier from a PIC output, but the PIC's clock itself is an LC
oscillator.  The TW523 and the original RR501 use free-running carrier
oscillators much like that in the CM11a.

				Dan Lanciani
				ddl@danlan.*com