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Main => Builders Discussions => Topic started by: ColinB on January 16, 2013, 12:50:55 PM

Title: Potentiometers
Post by: ColinB on January 16, 2013, 12:50:55 PM
Hi, is it possible to wire a Potentiometer to a PC keyboard (circuit board)?
Title: Re: Potentiometers
Post by: fsaviator on January 16, 2013, 02:25:03 PM
Why?  I guess it would be possible to wire a pot inline with one of the keys...  not sure why you would.  What are you trying to do?
Title: Re: Potentiometers
Post by: ColinB on January 16, 2013, 02:40:18 PM
I was just wondering if I would be able to use a keyboard circuit board to build a throttle quadrant, I can't afford to buy a proper I/O board at the moment
Title: Re: Potentiometers
Post by: iwik on January 16, 2013, 08:37:40 PM
Hi Colin,
What function do you want this pot to do. Pc keyboards are just switches, either closed or open. Putting a pot across one may cause some funny affects and usually the inputs are digital. That is either off or on. A pot is usually used so its can apply a varying voltage to what we call an analogue input and this may for example lter engine power. trying to use a pot on  pc keyboard wont achieve much. You need something like a Bodnar board which has
digital inputs for switches and Analogue inputs for Pots to handle things like  throttles ect.
Some cheaper options would be to get a Cheap USB joystick and modify. Sometimes these can be bought from flea markets ect for next to nothing. Strip everything out of it and build it into your throttle.
Hope this helps a little.
Title: Re: Potentiometers
Post by: ColinB on January 17, 2013, 12:08:30 AM
Thanks yes, it helps a lot. It was exactly what I was expecting.

I have my old Seitek AV8R but the pots only have about 60% function due to the wiring or some thing of the stick.

The Pots have dead zones at the beginning and end of the turns.
Title: Re: Potentiometers
Post by: Don on January 17, 2013, 01:48:35 AM
All of the products you need to help with can be found at http://www.hagstromelectronics.com/products/ (http://www.hagstromelectronics.com/products/)
the one you are after is the KEAD6 Potentiometer Interface

Don
Title: Re: Potentiometers
Post by: Joe Lavery on January 18, 2013, 12:32:19 AM
Colin,

I/O boards are not that expensive, the one I used when I built my TQ was from Leo Bodnar and only cost $34.99 plus postage. That gives you 8 analog axes, 32 buttons and a hat switch. If you prefer the same card with a full set of connectors it's $80.00.

http://www.leobodnar.com/products/BU0836/ (http://www.leobodnar.com/products/BU0836/)
http://www.leobodnar.com/products/BU0836X/ (http://www.leobodnar.com/products/BU0836X/)

Of course ther are other makes as well, but a lot easier than trying to hack a keyboard.  ;)

Joe.

Title: Re: Potentiometers
Post by: ColinB on January 18, 2013, 02:47:12 AM
Unfortunatly I am on sick leave from work at the moment which means I only just have enough to live on, I can't afford to pay out $30 for something like this.

Hacking a keyboard isn't actually that hard, just time consuming.

I will be using a keyboard hack for most of my button/switch functions for my first control panel as I already have that half built.

It will be used only for Lights, Master Switches, Icing, Fuel Pumps Buttons and Dials for Radio Stack (using 2 buttons in place of dials) and Gear and Parking Break.

It comes to a total of 59 key strokes used from my calculations and I have 80 avaialble without using special reserved buttons such as "ctrl".
Title: Re: Potentiometers
Post by: jonesthesoftware on January 18, 2013, 05:47:23 AM
Hi Colin
send me your home address to jonesthesoftware @ hotmail.com( remove spaces), I've got a spare Leo BodnarBU0836A you can have for free. Use it for all of the TQ axes as FS sees it as joystick axes so it's very easy to connect and configure
regards
geoff
Title: Re: Potentiometers
Post by: ColinB on January 18, 2013, 06:28:54 AM
Email heading your way now, thanks so much.

I never expected anything like that sort of generosity at all.

As and when I upgrade my hardware I will most definitely return the favor.