Re: remote antenna for DCF77 clock

Hello Bernhard,

The input circuit with the ferrite is usually a tuned circuit of pretty high Q. Theoretically you could run a coax and consider the capacitance of the coax as part of the tuning capacitor. But this will only work if the coax is short and has less capacitance than what's in there now.

The 'proper way' is to build a tuned circuit with a pre-amplifier, then run a coax to the clock. May need an additional DC wire to feed the pre-amp.

Simple question: Since you really only need the motor and gears where you want the clock can't you just mount the rest of the electronics at the window and feed the motor via a tiny cable?

Regards, Joerg

http://www.analogconsultants.com
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