Re: CM11A hangup: Any better products?

[Joerg <notthisjoergsch@xxxxxxxxxxxxxxxxxxxxx>]

Hello Dave,

> John Galvin reverse engineered a partial CM11A schematic. It's at...
>
>      http://home.pacbell.net/lgalvin/CM11AX-10a.gif
>
> It includes the oscillator.
>
> I think if you look at your RR501 you'll find it uses one winding of the
> same model transformer as is used for the input as the L with a couple of
> 27pF caps. They use so many of the transformers, they probably only cost a
> few cents. They assemble them in mainland China where production costs are
> nearly nil. After all, they tune the wireless devices by bending the single
> wire loop used in its oscillator.

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.

Regards, Joerg

http://www.analogconsultants.com