ORIGINAL: CGRetired That's odd. When I was in training, I used an Airtronics buddy box and never had a battery to charge in the buddy box. Perhaps you are thinking of using an RD6000 and another RD6000 as a buddy box? In that case, I agree. This is so with any other transmitter to transmitter as a buddy box configuration. When using an actual buddy box, there is no battery in the buddy box, just in the master transmitter. I have both the Airtronics and Futaba buddy boxes and neither have a battery in them.
In which case you are/were probably using simple old fashioned non computerised TX without EPA, dual rates, elevon / Vtail mixing etc. Like computers, modern TX are changing rapidly as even the modern 4ch Hitec Laser 4 & 6 must have a battery installed when used as a slave.
With many modern models requiring 6 channels for dual ailerons/flapperons the days of a simple 4ch TX as a buddy box are limited.
Please read all of the information relating to updated trainer systems supplied with my last post.
Regards
Alan T.
[link=http://homepages.ihug.co.nz/~atong/]Alan's Hobby, Model & RC FAQ Web Links[/link]