Hey folks, Question: I have a DX7 radio with a AR 7000 Rec. Servos are DS821 digital. It all came together in a pack.. The battery that was with it is a Spektrum 4.8 1100mAhr NiCd 4 cell Rx Pack. Now the question. Can I use my other batteries with these servos / system without any damage .. Here they are. JR Sport 1500 mAh 4.8 Nickel Metal Hydride 4 cell, and hpi racing 1200 mah nickel metal hydride 5 cell. If I can use these, which one would be the best to use. Thanks for your time. Pappywolf[sm=50_50.gif]

You shouldn't have any problems using either of those batteries.

The batteries you mentioned will do just fine. I use the JR sport 1500mAh packs in a lot of planes since the LHS seems to have them in stock on a regular basis. Just don't use anything smaller, especially with digital servos.

I agree with what has been advised above

However, if your using over 4 digital servos in your setup you need to rethink things.

Digital servos drain more power out of your battery so the playtime is less if your using say 6 servos vs 4.


I almost lost a Venus II about six weeks ago because I didn't have a large enough battery in the airplane. The problem occurred on the third flight with the Voltwatch indicating ......... ALL IS WELL!!!!!

I have now switched my thinking to using a 6 volt battery for everything beyond 4 servos, and then keep close track of the voltage after a couple of flights.

I too have the DX7 with several AR7000 receivers (of course, in several aircraft). When I started using this fine radio, I decided to go with 6 volt packs and at least 1200 mah packs. I have a few aircraft that have a pair of these batteries installed. And in every situation, I have a voltwatch installed.

As Steve, my setup saved my Venus II. One of the pair of batteries went bad during the third flight of the day. I never noticed it during flight because I was using two batterypacks. When I landed, I checked my batteries.. which is what I normally do after each flight. The one pack measured about 1 volt, the other was about still in the green, measuring, if I recall correctly, about 5.9 volts.

The main reason, though, that I use 6 volt packs is because I do not want to fall below that critical threshold voltage that caused the RX to "re-boot". This just can't happen with 6 volt packs because the point at which they require recharge is well above that threshold, but it is possible to reach that threshold using 4.8 volt packs. So, I simply avoid the problem by using the 6 volt packs.

CGr.