[TowerTalk] BCD relay driver ideas needed

[Rick Karlquist]

Pete Smith wrote:
> I bought an Ameritron RCS-10 antenna switch at Dayton, particularly
> because of its BCD control protocol.  My thought was to use the BCD band
> data output from my shack computer, running N1MM Logger, to control the
> remote relay box in parallel with the manual controller.  But in order
> to do that, I will need 3 relay drivers to supply the needed current,
> and presumably, will also need a level shifter because the relays want
> 12 volts, while my LPT port is 5.
>
> Has anyone already been down this road, so I won't have to reinvent the
> wheel?  Is there a way to use traditional PNP transistor source drivers,
> but with 5 volts on the base and 12 volts on the collector?


Use a quad opto-isolator.

See Digikey 751-1335-5-ND (16 pin DIP)

Rick N6RK