[time-nuts] Auto-fail-over switch

[Glenn Little WB4UIV]

source --- amplifier --- relay coil.

When source is present the amplified is detected and drives a relay coil 
to keep it energized.
When source fails, relay opens switching to backup source.
When source is again active, relay closes reverting back to primary source.
A 10 MHz xtal or other 10 MHz filter in series with amplifier input will 
ensure that amplifier will respond to source going off frequency.

Glenn

On 2/4/2019 9:26 PM, Jeff Blaine wrote:
> Wondered if anyone had seen some sort of gadget that would look to see 
> if there was a 10 Mhz signal and switch a relay (or provide some other 
> output) in the absence?  I would like to cook up some sort of fail 
> over switch without having to do much actual work. :)
>
> 73/jeff/ac0c
> alpha-charlie-zero-charlie
> www.ac0c.com
>
>
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Glenn Little                ARRL Technical Specialist   QCWA  LM 28417
Amateur Callsign:  WB4UIV            wb4uiv at arrl.net    AMSAT LM 2178
QTH:  Goose Creek, SC USA (EM92xx)  USSVI LM   NRA LM   SBE ARRL TAPR
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