Relay guide/tutorial?

[MPDerksen]

Is there a summary write-up out there that helps me understand the various antenna and dishes, and what to do with them?  I get stuck here and there when there is no signal for my OKTO, or whatever.  Particularly on the backside of Mun.  Is the correct solution to put a few satellites around Mun as relays?  I assume these could be REALLY small and simple.  

[Aegolius13]

You're correct - your antenna is not working because it has no line of sight back to Kerbin, but that can be fixed with relays.  

As far as which one to choose,  this page has a nice table showing the effective range of different combos of antennae.  

https://wiki.kerbalspaceprogram.com/wiki/CommNet

As a very general rule of thumb, it works well to use the 2gm* for relays on Mun/Minmus, the 15gm for relays at Moho / Eve / Duna, and the 100gm for all other bodies (and for master relays at Kerbin to deal with eclipses and whatnot).  There's also an argument to be made for using bigger ones everywhere you can, as sometimes you can get unexpected but helpful transmission paths.

You don't need a relay on the craft you're attempting to fly, just on the other antenna forming a bridge.  That said, the only disadvantage of a relay antenna is weight/size/cost.  They can do everything a regular antenna can do, and more.

 

*You can probably get away with the 5mm one for the moons, but I've just never liked that one. 

[MPDerksen]

40 minutes ago, Aegolius13 said:

You're correct - your antenna is not working because it has no line of sight back to Kerbin, but that can be fixed with relays.  

As far as which one to choose,  this page has a nice table showing the effective range of different combos of antennae.  

https://wiki.kerbalspaceprogram.com/wiki/CommNet

As a very general rule of thumb, it works well to use the 2gm* for relays on Mun/Minmus, the 15gm for relays at Moho / Eve / Duna, and the 100gm for all other bodies (and for master relays at Kerbin to deal with eclipses and whatnot).  There's also an argument to be made for using bigger ones everywhere you can, as sometimes you can get unexpected but helpful transmission paths.

You don't need a relay on the craft you're attempting to fly, just on the other antenna forming a bridge.  That said, the only disadvantage of a relay antenna is weight/size/cost.  They can do everything a regular antenna can do, and more.

 

*You can probably get away with the 5mm one for the moons, but I've just never liked that one. 

Helpful.  thanks.  I have a mission to rescue a Kerbal from the dark side of the mun.  I wasn't thinking, and had a lander with just an OKTO.  I think you can guess what happened.  Now I'm building a lander with an extra seat, but the fact remains I'd like to stay in contact more than I am.

I also need to figure out how to get a science bay down to the surface of Mun, and home so I don't have to transmit everything...  

[bewing]

I think I already asked you about your "no control without signal" setting, and you said you turned it on like a crazy person. This is why.

If you leave that setting on its default (off) you can still fly a mission without relays. For directions, you are limited to what you can do with the navball. For thrusting, you are limited to pulsing your main engines off/on. But that's enough to get you anywhere, and when you get there you can still do anything -- provided you build your ship carefully.