[Antennas] DC voltage on coax

[Nelson Wittstock]

I am currently enjoying using a pennant receiving antenna for 160 meters.  I
would like to add another for a different direction but this means having a
DPDT relay at the junction of the pointed ends.  I need to get voltage to
the relay and I would like to do this by routing the voltage through the
coax feed.  Can someone direct me to a site showing how this can be done?  I
know I have seen plans for it but cannot find the information now.

Thank you,
Nelson  -  K8DJC