View Full Version : I'm not spending $100 on a rotary switch...

11-20-2008, 08:20 PM
Hello everybody. I need a rudder trim knob, but the cockpitsonic one costs over $100, and it just comes with that and a parking break!

I'm not too good in the electrical field, so I would like the closest to 'plug and play' that is possible.

All I'm looking for is a small rotary knob.

Any ideas?

11-20-2008, 08:40 PM
If you know the specs of it, check Mouser.com and you should be able to find a very inexpensive one.

11-20-2008, 09:32 PM
Does Mouser have a distribution center in Switzerland?

11-20-2008, 10:06 PM
Which rotary switch you are looking for?



Efe Cem Elci
11-21-2008, 04:13 AM
He could always try Conrad or Distrelec. Having lived in Switzerland, those two companies have proved useful in getting parts for the sim, especially if you know French or German.

11-21-2008, 02:31 PM
If for the 737, it is not a standard rotary
The knob turns about 20-30 degrees either way left or right and self-centers.

11-22-2008, 06:08 PM
If you have the space you could make something with a couple of springs and some micro switches?


11-23-2008, 06:35 AM
i have been thinking about your couple of springs and mirco switches idea interfacing with the bu0836x card i like the idea and think i could work but any thoughts on how i could show the rudder postion using the leds show the 0 through to15 degree on both sides.?

would i need a little circuit or something

regards john d

11-23-2008, 09:42 AM
Well, you could either use a potentiometer as the main spindle for the whole switch and take that off to an input card to process and then have various outputs leds triggered at certain voltages. If this isn't working you could always gear the shaft to a pot to get more resolution.

Come to think of it a dual pot might also work, one track for the leds and the other for the input instead of switches.....something along the lines of the flaps pot in fsuipc?

I don't see any real problem doing this, I have a bu0836X and have been thinking along these lines for the parking brake and tiller, that's why I mentioned it here.

Hope this helps and please put up a photo if you get it all to work!


11-23-2008, 11:26 AM

You could even use one of those 'bar graph' driver chips....the ones that are used to drive the volume indicators in some audio devices. Then the dual pot could use the second track to drive the display chip as it's only measuring the input voltage and using that to decide which leds to light.....Just a thought!

Also, if you are after small springs for this I got a big box full at Maplin for 2.99 - not bad for 150 assorted springs!


11-23-2008, 11:53 AM

Mechanical solution. Works well.

11-23-2008, 02:22 PM
There you go again Jack, Posting well thought out, simple, easy to implement ideas.
The nerve of some people... :)

11-23-2008, 03:19 PM
Try my best Andy, try my best!

11-24-2008, 06:18 AM
i like that idea jack ... as i am not an expert in the electronics i think i could handle your idea ... can i ask is this how you made your one? ,,, also what type of servo would you suggest .

regards john d

11-24-2008, 11:25 AM
Hi John
you resurrected an older post "737 pedestalTrim Gauge"
I put some more detail . Go to that thread.
Any cheap servo can do as long as the gearing is Ok.