More general than just Hitec related, but transmitters are generally run off of 8 AA batteries, right.

So for alkalines this would be 12v, but then with NiCd or NiMH batteries we drop it down to 9.6v. Are we giving anything up by doing so? Would there be an advantage to running a 10 cell pack to run 12v for the rechargables?

Back in the day [granpa voice] ooh, those were the days [/granpa voice] we exchanged alkalines for 500 - 600 mAh NiCds, but now we live in the age of 700 mAh AAA NiMHs so 10 AAAs could easily fit in the space of 8 AAs.

Would it change the function of the radio in any way? Would there be any advantages or disadvantages either way?

I'm just thinking if the difference between 4 and 5 cells can make a difference in RX packs, then can the difference between 8 and 10 cells make a difference in TX packs?

When NiMh's/NiCd's are just fully charged, their voltage increase. My 8 cell AA NiMh reaches well over 11 volts.

So be carefull with 10 cells. When fully charged, the voltage might get higher, than your TX like. And when the smokes come out, the function are gone too....

Personally, I'm using 1100 mAh's in my TX. With those, I got plenty of runtime. I never had a problem with range, nor glitching. So I prefer to be on the safe side.

But if you're having problems with runtime/range/glitching, you might try with 9 AAA. This way, it's a little more safe than with 10 cells.