Rick & Jim - so much old text it is hard to find the new stuff.
>From Jim's comments:
> && I did notice that on any of these 26.5 vdc latching type
relays..that
> the coil resistance on em is very low..and blows my 5A current limited lab
> supply into the red. A quick pulse of 12 vdc is more than ample
> to operate a 26.5 vdc latching type vac relay.
>
> later....... VE7RF
>
K0TO response => For me the simple solution was to put a series resistance
followed by a shunt cap across the supply leads to the relay. The cap
provides a quick burst of current and the series resistor limits the final
current. I allow just enough final current to 'warm' the remote relay coils
located at the base of the tower. [temp this morning in Idaho was 3 deg F].
Since the circuit can be built with current directing diodes, only one pair
of wires is required [actually n+1 for n co-located relays being
controlled]. The control line for each relay is switched between + and - to
change the latched state.
Tod, K0TO
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