Selecting the right parts....

[danjbrierton]

So i'm brainstorming and researching for an upcoming DIY controller, and i have a few questions i can't find answers for. Any expertise would be appreciated.


1) how do i know what specs to look for when selecting hardware?

I've done some browsing around, and most sites don't list any specs on the components they have. For example, livid instruments lists nothing about their rotary pot except that it's a rotary pot. pioneer dj replacement parts won't even give you the option to buy a pot, you have to buy the whole board. i've been looking for pots with and without center detents. center detents are much harder to find. here's what i came up with: http://www.mouser.com/Search/Product...8-RK0971110D7F

Now i have no idea if its going to work. What resistance range should i be looking for? What power rating?



2) what is a good shaft length for chroma caps? 9mm? 10? 15? anybody know how deep the shaft slot is?

thats pretty much it for now. thanks in advance,

-DB

[ReggieUK]

You'll be bound by the adc stage on your microcontroller but typically, 10K ohm Linear pots are used most and the microcontroller ADC pins will be low current so I wouldn't worry about the power rating.

I'd start by looking for part numbers, there are repairs and spares places on the internet that have pictures and sometimes part numbers, you might get lucky there, or get lucky and find someone that owns one and ask them to get the part numbers for you. Alternatively, you could speak to mouser/farnell/RS(uk) etc. sales rep. and tell them what you're looking for, they may be able to help.

I'd like that information on chroma caps, I tried asking on the live chat but they didn't have the information, what we need is one of the DJTT team to get the shaft length, diameter and style for the knobs and shaft dimensions/height for the sliders.

[danjbrierton]

i opened a support ticket. let's see what they respond.

-DB

[danjbrierton]

i didn't even thing about the shaft width :/ what is standard? 9mm? 12?


i bought some 10k and 20k pots w/ and without center detent from furltec, i'll let you know how prototyping goes.

[ReggieUK]

it's generally 6mm but it can be split and knurled or a 'D' shaft. I *think* the chroma caps at least for the numark mixtrack pro II are D style. I wonder if they realise that geeks like bright colours too? they'd make an absolute killing on somewhere like sparkfun or seeedstudio.

As for buying potentiometers, for the most part it probably isn't going to bother either of us, I spent £1 each on mine, they probably come from china, somewhere. They're smooth from top to bottom, I don't get any weird jumps at all, so they're good enough.