Topband: Two wire beverage question

Guido Tedeschi guidoted at gmail.com
Fri Mar 23 15:46:47 PDT 2012


Il 23/03/2012 16:10, Kenneth Grimm ha scritto:
> Both of these boards appear to have an electrolytic capacitor
> installed.  On both boards the electrolytic appears to be associated with
> the direction switching relay.  None of the two wire beverage diagrams that
> I have seen have such a cap and I wonder what its function is and how it is
> connected in the circuit.  I am told that the value is 100 mfd @ 50 volts.
>
> Apparently the cap isn't necessary, but since I have a few in my junk box,
> this might be an opportunity to put one of them to use!
>
If you are talking about the RBS-1P, the electrolytic  capacitor is 
connected in parallel with the relay coil (positive terminal of 
capacitor connected to ground), after the diode with anode connected to 
the relay, and it is needed because you can switch the direction also 
with an AC voltage (about 8-9Vac).
If you will never use an AC voltage but only -12Vdc, the capacitor is 
not needed...
73 de Guido, ik2bcp



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