2 x batteries for electric plane?

Hi There
I am about to get my first electric plane - probably a slow stick type plane.
However, I can't
figger out how to arrange the batteries -
eg if the plane uses (say) 7 cells to run the motor then that gives 8.4 volts -
but that seems
too high for the receiver and servos. Or is it? I note some motors use even
higher voltages.
I thought about installing a 7805 voltage regulator to provide 5 volts for the
servos and radio,
but as I haven't seen any reference to that in ads or newsgroups I am wondering
if indeed the
radio and servos will be OK on 8.4 volts.
David

The ESC (electronic speed control) includes a BEC (battery eliminator circuit) that powers your receiver as well. You don't need to add anything else! You can always use a separate battery pack for the receiver but WHY? It's just extra weight and weight kills electric airplanes! Give us some more info regarding the size motor you will be using, etc.
Towerhobbies has a number of different ESC's. You have to use one of sufficient size to handle the amps. Ask questions here. Lots of us here can help you!
plane. However, I can't volts - but that seems even higher voltages. the servos and radio, wondering if indeed the

However, I can't - but that seems higher voltages. servos and radio, wondering if indeed the The speed controller has a 7805 type regulator built in. Its called a BATTERRY ELIMINATION CIRCUIT (BEC)
Power from the flightpack is regulated and fed dwon the servo wire to power the reciever via the servo connector.
Only if you exceed 10 cells does this simple form of regulator become too stressed to be relaible,
when a separate regulator (UBEC) or separate reciever battery is indicated.

The speed controller will regulate the voltage to the rx down to the proper level. Nothing else is needed.

Thanks guys - I didn't know the regulator was built in.
David

Read carefully-not all Electronic Speed Controls have Battery Eliminator Circuits included. They will say BEC, if they have them. Make sure the ESC's can handle the amps that the motor is going to draw. -- Jim in NC