Which manufacturer are you guys ordering your potentiometers from? any particular store/site you might recommend?
thanks!
Depending on your needs, Radio Shack can help you if you need it “right now”, or else Digi-Keyhas a wider variety of pots available but of course, it’s the shipping that may effect your time constraints and deadlines especially during the build season.
Always good to stock up on the one you use cause extras are kinda hard to come by when at a competition.
When choosing a potentiometer, pay close attention to the devices expected lifetime in terms of the number of rotations. Many/most low cost parts have relatively short rotational lives, and may prematurely fail even with seemingly little axial or lateral loading applied to their shaft. Remember, most of these devices are designed for use as user input devices that will see little use.
For position sensing, fortunately there are some specialty parts that are well suited for this purpose. Bourns 6639/6539, Vishay/Spectrol 357, or Vishay/Spectrol 157 are all good choices.
Pricing is currently in the $11-20 range, though the Bourns part in the ‘servo’ mount is closer to $50. All are in stock at Mouser and available for overnight delivery.
These parts allow for continous rotation and have a sensing range of 340 degrees, so even if you do have something come loose and attempt to rotate the pot beyond its sensing range, you won’t damage anything.
Depending on your application ( 1 turn or multi turn ) consider these active encoders.
http://www.usdigital.com/products/ma2/
They price out at ~ $29.00US and won’t break if you pass 1 revolution like pots with a stop.