The "upgrade" to 6 volts with the DX7 was due to a problem they had with low voltage "reboot" issue with the receiver. If the voltage dropped below a threshold, and I'm not sure what that threshold really was (or is) the receiver would re-boot or cycle. The time it took would cause some problems (politicall correct for crash.. [X(] ). Spektrum has changed something so it does not do this any longer.

I simply moved up to 6 volt packs to avoid this. I also went up to 1200 mah packs, and is pretty much what I use on everything now.

CGr.