"Old Style" Artronics connectors

[Robert Parisot]

Howdy Folks!

I picked up a Hitec 555 in the For Sale forums several weeks ago, wired for the older Airtonics connectors.

From the ad:
"It's an RCD8400, which (IIRC) is the "old style" Airtronics pin configuration. All this means is you'll have to swap the + and - wires on your servos and ESC. If you're not sure what this entails, this is not the receiver for you!" Piece of cake! (me thinking....) :)

Finally got around to ordering some crystals from Dave, at Radical RC, (great people!), and last night I made the proper pin changes to my servos and ESC. I've got an old Airtronics receiver, so I tested my setup using it, and it worked fine. Next, I hooked up the 555 Rx, nothing. No servo movement, motor control, (and no blue smoke either!). :) The only thing I noticed was the BEC regulator getting warm, and a spot on the bottom or the Rx getting HOT.

I've included some images. The hot spot is under the S, at the transistor, and to the left, at the other black device. Seems odd to me that the neg. lead of the cap is connected to the positive strip on the board, but it's been a while.

Am I missing something? Any help is appreciated.

Thanks!
Robert
:)

[Robert Parisot]

Worked fine....
:)

[uav51]

I think you kind of found your problem with the capacitor. What you have drawn in the picture as + should be -. Your second picture in your first post should be s + -, that is how that receiver looks to be set up (pretty darn sure). The negative side usually runs around the board as many things will just connect directly to ground, while the positive voltage has a much more varied path. Hope nothing got fried. Maybe it was just set up for positive shift instead of hitecs usual negative shift.

[Robert Parisot]

Hooked it up the "regular" way, S + -, and it worked!

I guess I'm relieved, but now I have to wonder if it's safe to fly with it...having had it hooked it up wrong for a couple of minutes. Funny, the guy who sold it to me said he'd flown with it many times.

Mm....

Just e-mailed Hitec, I'll see what they have to say.

[daddysard]

Robert:
I have a bunch of "Old " Airtronics stuff... My guess is that the receiver was marked Airtronics, meaning it was a positive shift (JR-Airtronics) The pin assignment were not changed, but kept as what you call regular (+ in the center). I would just do a Range check! Remember to swap the wires when you change from Air to Hi. I color code all old stuff (+ on end) with Day-Glo Orange Good luck John Sard