Relay RA-15 useless?

[kerbalfreak]

The RA-2 seems great to make constellations around bodies. I've made very nice constellations around Kerbin, Mun and Minmus, with 100% signal, anywhere, always (or until the Kraken change all the orbits). To reach 100% on Minmus I used some RA-15 orbiting Kerbin between Mun and Minmus. I know that reaching 100% don't have benefits, but I like the achievement.

Now I'm wanting to go interplanetary, seems that with I place some RA-100 after Minmus, the RA-15 that I placed will become useless. I plan to place some RA-100 around Kerbol, and orbiting the planets I want to cover. And constellations of RA-2 to provide 100% surface cover. And never needing the use the RA-15 again.

Is there any specific use for the relay RA-15? I play on sandbox, and my goal is to reach 100% cover everywhere.

I'm using this tool to calculate distances and signal: 

Thanks!

[Draalo]

1 hour ago, kerbalfreak said:

Is there any specific use for the relay RA-15? I play on sandbox, and my goal is to reach 100% cover everywhere.

Of course. Other Planets have moons too.

Send a big relay to the planet, cover the dark sides(*) of the moon(s) with some tiny sats.

*Dark in the meaning you dont have line of sight to neither Kerbin or the planetary relay. 

[Snark]

 

2 hours ago, kerbalfreak said:

Is there any specific use for the relay RA-15?

RA-15 certainly has uses.

• For career games:  the RA-100 is pretty high up the tech tree.  There's generally a pretty long segment of a career game in which the player has the RA-15 but not the RA-100.  (Of course, this doesn't apply to you if you're playing sandbox.)
• The RA-15 is considerably smaller and lighter than the RA-100.  If you have a case where an RA-15 is enough, it means your ship can be smaller/lighter.
• And, as @Draalo points out, small relays are always useful for covering the back sides of planets and moons.

[kerbalfreak]

Thanks for the replies!

I think I'll send only one cluster of RA-100 to each planet, and some RA-15 when the planet has moons, to redistribute the signal when the main one get blocked. Better than two or more clusters of RA-100.