Hi 3DNater
I think your concerns are justified, but not always a concern.
Here's the thing - of both options you have a couple concerns
Option 1) goes with a battery for RX and one for IG.
Problems:
2 batteries to remember to charge
2 batteries to fail (if EITHER fails your plane still likely crashes)
Pros:
Likely isolates noise from engine, however we have EVEN seen with 2.4, vibrations from the engine (without ANY electrical connection) affect the RX. Unlikely but could happen
2) Single battery:
Pros:
One battery to worry about and maintain properly
Cons: if it fails your plane goes down (similar to the above, it only takes one to fail)
Possible engine noise
We have found that if you TEST your RX in the following way we have NEVER experienced noise in flight.
Use your test button (usually limits signal so you can move about 60 ft. or so away before the RX stops responding cleanly). Test with engine OFF.
At the EXACT point it stopped working with engine off now test with engine ON (PLANE FULLY RESTRAINTED!)
IF it starts acting funny or stops responding SOONER than do NOT fly! If it fails to respond at the same point the noise is not affecting signal. Test several times
REALITY:
there are MANY MANY ways you can set up your system. I know guys will use power boxes and 2 RX's and more to try to create redundancy. But with EACH piece you add you add complexity and possible failure points.
It is up to the individual to decide what is the best fit for them.
Speaking of power boxes, I think the simplest way to add some redundancy without a lot of complexity is our Power board - specifically the black unit.
Reason being, you can hook up 2 batteries:
they draw evenly (balance as they draw)
also protect against SHORT circuit. this is a biggie. If you go with 2 batteries but do not have short circuit protection and one shorts your plane goes down almost instantly.
Anyway, there's a lot to cover on this subject. Maybe we'll make a video on it one day