I have been using real flight since back in the RealFlight Deluxe days, slowly upgrading along the way. As of today i have the G5.5 software the original interlink controller, not the newer interlink plus. The switch arm, but not the body itself, at the top right of the transmitter broke. The airplane i fly most often is a U-Can-Do 3D 60 from the swap pages, and on that particular model, the switch in question controls the smoke. After the switch broke, i inserted a paperclip into the switch and that allowed me to change the position of the switch reliably, and thus the smoke ON/OFF. Not being someone who enjoys kludging a fix together from duct tape and bailing wire, i order a replacement switch from Tower with plans to swap it out. I desoldered and removed the old switch, and the soldered in the new switch. Everything was wired correctly and the pins were soldered properly. However, the plane is now stuck in smoke ON mode. I checked the switch, and the pins on the board of the transmitter and the switch is properly making and breaking the connection, depending on the switch position,but i can't get the smoke to turn off. Itried restarting the software several times, putting the old switch back in etc., but nothing seems to work. Any idea what i should check next?

It's the type of switch you purchased that is to blame.

It is likely that you obtained a switch that looks exactly like the one you are replacing, but it works differently.

With the controller disconnected, put an ohm meter up to one of the other identical working switches and observe the switch positions and where and when you get continuity.

You'll need to get a replacement that works the same way.

No i checked everything before and after, and the switch performs identically. I even put the old switch back in and the smoke doesn't turn off.

Go into the Windows Control Panel, and find the Interlink under Joystick devices.

You can calibrate the controller and observe the input signals from the Interlink there.

Verify that your switch is working.

I'll bet it is not.

Check the continuity from the wires back to the circuit board itself at the solder points.

It is unlikely that you damaged the circuit board itself given that the Interlink should have been unplugged when you did this.

However either the switch is wrong or bad, or you have a problem with the wires. The latter could have easily broken while you were working.

Perhaps I not have been clear but...

means that I have checked the continuity of the wires, and the signal goes from continuous, to broken when the switch is flipped and back again. I hold the terminals of the voltmeter, set to the "ring out" or continuity function, on the solder connections where the wires terminate on the circuit board.  There is no continuity when the switch is off, and continuity when the switch is on.  In either case, the smoke stays on...

Check the Windows Control Panel applet.

ok i'll check there when i get back home.  Is checking it under the control panel in windows better/different than checking it under the controller calibration screen under RealFlight?

Yes.

Windows will bases it's own calibration differently than Realflight.

Some problems are resolved by first calibrating the controller in Windows before doing it again in Realflight... so that Windows does not set too low of a travel limit for the controller.

i don't have joystick devices under device manager....
i have a LOT of USB interface devices though...

i calibrated the controller under RF interface and that fixed the problem thanks

In retrospect, i can't believe i didn't think to do that myself :| hehe, that why i have friends at RCU

Wonderful.

Glad you got it sorted out!

Obviously your re-wiring worked perfectly too!

Well i guess i spoke too soon.  I went back in to RF and the smoke was on and i couldn't turn it off again.  So i went back to try and calibrate the controller, and no matter how many times i flipped the switch back and forth, it would not show the channel at 0%.  It just stayed stuck at 100%.  So i guess i now need to find the windows calibration for this controller.  But like i stated before i dont have joysticks in my device manager.  Where else would this RealFlight InterlinkPlus (not Elite) Controller be located?

Ok in Windows 7 here is where you can find the calibration for your interlink, in case anyone else ever needs to know...

Hit start button
Click Devices and Printers
There should be an icon under Devices that looks like a black and gray xbox controller, with USB input device under it.
Right click on this icon and click Game Controller Settings
You should see Interlink under controller and status "OK"
Highlight interlink and click Properties button in the bottom right corner.
The test tab should be displaying.  If you give inputs to the controller, sticks, knobs and switches you should see the plus sign move, the sliders next to z-axis, x-rotatino and y rotation move, and you should see the buttons light and return to dark.
If it's not doing something right, click on the settings tab and click calibrate. It will tell you what to do to calibrate the controller.
Here are the assignments:
Z Axis - Throttle Stick
Y Rotation - Rudder
X/Y axis - Elevator Aileron Stick
X-Rotation - Flap Knob
Button 1 - Dual rate 2 Position switch on the front left of the controller, above the throttle stick
Button 2 - I assume this should be the Top Right switch, smoke in my case, but i can't be sure, as mine will not work.
Button 3 - Red Reset Button on the bottom left of the controller
Button 4/5 - Three position switch.

And i got out my multimeter again.
with the switch pushed toward the back of the controller the connections on the board are not continuous.
With the switch made, or in the forward position, the connections on the board read 0.2 Ohms and "ring out"
I'm at a loss now.The wires are not loose at the solder points or anything. I'm at a loss now...

ok, i just reconnected the controller and now it shows as working in the windows calibration screen
  Button 2 lights up and goes off with the switch...

And now it's stuck in the on position again.  I just can't figure it out.  I took the controller apart again and even when i know the connection is broken, and it's showing no continuity on the wire terminal on the circuit board, the smoke will not turn off.