Choosing a Potentiometer

[mrcirrus]

I'm building a glider sim using a real 2 seat fuselage for my club www.gliderpilot.info I have a Leo Bodnar BU0836X. I'm Choosing pots and would like some advice.

His site states 1k to 100k pots are fine, given the choice which should i buy 1k or 100k? - what difference if any, will it make to the finished product?

Rotary or Slider? Is it just a case of which arrangment suits the mechanical linkages best. Or is their an electronic reason for choosing a rotary pot. (Leo only seems to sell rotary pots which makes me wonder if they are prefered)

From this website ive found links to various sliding pots ranging from 70p each to £5 each. Whats the big difference? is it just the life cycles? will i get nothing but trouble from a maplin 70p pot?

Thanks for any advice.

[No Longer Active]

Welcome to MyCockpit.org

Firstly, in my opinion it doesnt matter what pot you use, you can use either 10k or 100k potentiometers, but most importantly make sure that your pots are LINEAR which is very important.

Electronically you will see no 'visual' difference between a 10k and 100k pot, i use 10k's and 100k's, and the activity difference is 'nill' between the two. At the end of the day the pot's range is still 0 and 100 whether it be a 10k or 100k.

Which pot you use is entirely upto you. Its different pots for different uses.

I use 10k slider pots for my throttle quadrant, as i need a sliding mechanism to 'push and pull' a lever, so a slider pot is brilliant for this. A rotary pot will be good for any type of rotary axis such as a flight yoke or rudder pedals where you will need to turn left to right or push forward/pull back for a flight yoke. Rudder pedals need a rotary pot to yaw left and right, and also rotary pots are excellent for toe breaks on the rudder pedals.

Its entirely upto you how you use each different type of pot, you may find that you need a few encoders which are similar to pots, but doesnt specifically need to be an axis, it can be used to control and up and down movement such as a radio or trim wheel etc.

As for buying pots.

Maplin are good but way over priced, general life span of a maplin pots are fair. I use ebay for most of my bits, you can get some good deals on ebay. Brand names such as Vishay offer excellent quality and lifespan/cycles. Try mouser electronics and difinately visit rapid electronics they are really good. Leo sells some excellent components, worth buying off him for rotary's, but for slider pots i go on ebay, you may be able to find 100mm linear slide pots on ebay too!

Hope this helps

Alex

[mrcirrus]

Thanks Alex, that all makes sense. I had read some of your postings which have some useful links to Pot suppliers, i'll take a look on e-bay. I might be picking your brain again when we start wiring the BU0836X. Or did you use the BU0836?

[No Longer Active]

Hey pal,

I use the BU0836 but i use a matrix to get get 32 outputs from the 12 output pins on the card!

BU0836 is easier, but you can get 3 BU0836's for the price of an 'x' model if you can be bothered to make a matrix.

PM me if you have any questions!

Nice one!

Alex

[cscotthendry]

Hi and welcome to the forum.
If the documentation says that any pot from 1K to 100K is fine, I'd go for the 1K pot. The reason has to do with induced noise into a high impedance circuit. The lower the input impedance to a circuit, the more immune it is from picking up noise created by the likes of fluorescent lights or computers.

Hope this helps.

[mrcirrus]

Hi Scott,
That answers my question, thanks
Another basic question -Wiring between the pot and Leo Bodnar BU0836X controller what grade of wire do you normally use.
I was thinking single strand would push easily into the self connectors or do you use multistrand and "tin" the end.
How thick should it be, what do you guys normally use?

So pleased i found this site - its a goldmine of information!

[Rodney]

You can use 22 or 24 ga wire. Single strand is used where vibration or movement is not a problem. If you "tin" the end of a stranded wire you make that end more or less a single strand and again where movement may be induced, it may fail at that tinned point. But we are talking non critical applications.

Here is a link to explain pots. http://sound.westhost.com/pots.htm