How to make a relay dish relay a signal?

[PTNLemay]

I'm working on expanding my communications network, and I've run into an odd problem.  My booster sent up the satellite into a really high 70 million meter orbit, but I specifically left enough fuel in the booster so that it could bring itself down to Kerbin.  It has a little probe core and batteries to last the maneuver.  The relay is online, but the booster doesn't see it.  It says no signal.  Other satellites nearby do see the new relay, but not the booster... It says that probe core has a basic antenna in it that should have a 5 km range, but does it not with relays?  Are those only for Kerbin-based transmitters?

Here's a picture of the two right after separation.

[JPLRepo]

Well I just checked.. and I have no relay issues with the probe built in antenna in a  similar simulated scenario.
Can you supply a bit more info as the picture is impossible to tell what you actually have there.
I can see the active vessel has a connection but which one is that?
What kind of relay? does it have power?
Does the booster have power? is it in hibernation mode? What probe core is it using?
Can you supply save file/craft files?
 

Spoiler

 

[PTNLemay]

... nevermind, I just realized my mistake.  I used the regular dishes, those aren't relay dishes.  So they won't be able to relay.  It's just a very expensive and very useless satellite, able to perform one-way communications.

[JPLRepo]

ah right. No Relay dish. Never mind.

[nholzric]

I've had the same problem - detach a rocket body (with probe and power) from a space station which has a signal in order to de-orbit but discover that the built in antenna on the probe can't connect to a signal across the 10's of meters to the space station. My space station, just like your "relay satellite" didn't have a "relay dish" on it.

But here's something I don't understand - my early satellites around the Mun sometimes cross link with each other, and they don't have relay dishes on them. Are there some situations where regular (non-relay) antenna will be used to as a link? Is a "relay dish" only needed for transmitting science or conversely only needed for transmitting control?

[bewing]

You are probably using the HG5 antenna at the Mun, and those ones do have relay capability.