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
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Most of the ESC's have a regulator built into them. They also have a cutout circuit that allows the receiver and servos to operate with the motor shut off do to low voltage.
No need to reinvent the wheel on a slow stick.
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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

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David wrote:

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.

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The speed controller will regulate the voltage to the rx down to the proper level. Nothing else is needed.
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Dan
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Thanks guys - I didn't know the regulator was built in.
David
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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
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