I have a JR 7202 heli version, and a JR Sport s400. I do not have a battery for the s400. Do I need one. I was told I can buy a cord from radio shack to connect the two. It looks to be a standard double male adio cord. Is it a mono or sterio connector. How do I set the two up once I have the proper stuff. I don't even know who holds what and how.

Can't tell you much about the connector or cord, but the setup is simple. Start the plane (or whatever you are going to be using with the buddy box setup), then set all on the buddy box to neutral except throttle. Set that at min. Operate the buddy box switch on the master and see if anything changes on the plane. If elevator moves, for instance, switch back and forth from the master to the buddy box while adjusting the trim on the buddy box until the elevator does not twitch or move when switching back and forth. Do this for all control surfaces and the throttle. Once all are set so that the control surfaces do not change during switching back and forth, you are all set to use it, they will both be the same.

Hope that helps.

DS.

Usually JR buddy boxes need a battery pack to operate because the connector cord doesn't have enough wires to supply power as well as signals. That why I suggest to new flyers looking to buy radios that they consider Futaba or Airtonics radios instead, 1 less battery to worry about. [8D]

CGRetired is on the right track but do it the first time with the engine off. Just in case you need to reverse some servos (especially the throttle), it's easiest to do it with the engine off. Once preliminary settings are done you can repeat with the motor running so you can set idle on the buddy box. Don't expect trims to match between the 2 boxes, it's unlikely.

I applaud your decision to get help from an instructor. The instructor will check all that out for you. Please make contact with him sooner, rather than later.

Best wishes,
Dave Olson

ps the JR's I'm familiar with do require a fully charged battery in the student controller.

This is the JR trainer cord
http://www.horizonhobby.com/Products...ProdID=JRPA130
not so expensive that you need to worry about Radio Shack or the like.
There are also cheaper ones available that will work
http://www.horizonhobby.com/Search/D...ER+CORD&CatId=

This REALLY should eliminate RS from the picture. Your LHS should be able to get you one or order it yourself. Your instructor may already have one too. I know I keep one with me at all times.

Most JR Buddy Boxes can be powered sufficiently by a standard 9-volt battery.

Ken Erickson

True buddy boxes are like this but using a standard JR radio as a buddy box means properly charging it.

Bruce88123 speaks from experience, I'm sure. So do I. A standard JR radio used as a buddy box will quit operating when the battery is low. No big deal, the instructor just takes control, lands, and puts the box battery on charge. But it happens.

Good luck,
Dave Olson

Hi Bruce.

Yep, I should have noted that reverse switch configuration is the first thing to check, without the engine running. Could be rather interesting if one did the check and found the throttle reversed with the engine running! Thanks for correcting that.

DS.