where to find good 10k pots for a teensy midi controller

[thealienthing]

Hey guys, I've recently come to the close of a long and difficult first project with a teensy midi controller. The biggest setback I've had in the end is that my pots are terrible! I bought these pots from uxcell (5 for 5 bucks now 2 bucks! thats how bad they are) and 4 out of 5 have gone to hell. I need to find some pots that will last a while without giving overly jittery readings (like a jitter of 300 on the 0 - 1023 range).

TL;DR where are the good 10k pots! Mouser, amazon etc. links would be greatly appreciated

 

[GremlinWrangler]

The poor quality pots are probably goners, but you could power it down and try a squirt of isopropal alcohol or contact cleaner onto the wiper if you can find a position where you can see it and then sweep the full range. If they've used corrosion prone materials that won't help forever but may tidy things up a bit till you can get replacements.

 

[tonton81]

you could use digital pots, controlled by i2c/spi. some have 128 steps, some have 256 steps for precision.

 

[oddson]

You can spend $20 for some fancy pots with wire-wound or conductive-plastic contacts.

My local store has a basic wire-wound 10k for CDN$3 (US$2.30ish).

Wire wound are still susceptible to corrosion but not the surface degradation that kills carbon contact pots.

... but do consider my suggestion to your other thread that your testing code may have a problem. That many bum pots seems unlikely even for bargain parts -- cheap pots will wear out quickly, perhaps, but they shouldn't be that spotty out of the bag.

 

[GremlinWrangler]

@ oddson, the dodgy pots may have been stuffed in a corner for a decade or so sharing space with solvents which can be fun, though as you say even a poor pot should be relatively stable stationary even if it's linearity is awful.

Valid test would be to swap out two fixed value resistors with the same total resistance and see how that reads.

 

[Theremingenieur]

I'm not sure if the reading problems mentioned in the first post come really from bad potentiometers. Other issues might be bad grounding, bad Vcc decoupling and the lack of 10nF capacitors between the wiper and ground to buffer the shortly varying ADC input impedance during the conversion due to the delta sigma principle.

 

[tubelab.com]

I used these 858-P0915NEC15BR10K from Mouser in my two synth breadboards. The big one uses 8 to 1 multiplexing so that I can connect 49 pots to a T3.2 (now upgraded to a T3.6). The pots are used for controlling everything EXCEPT absolute pitch (VCO frequency). I use ALPS rotary encoders for pitch tuning. The synth has been operational for about 8 months and I have found no issues with the pots.