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A good way to mount "swappable" potentiometers in a pcb?

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autotel:
As a hobby project I want to do a passive audio mixing board. I would like to make this board more eco-friednly, and one problem is that potentiometers have the tendency to become noisy with time. I decided to think of ideas how these can be changed later without wearing off the board.
I'd like to find an elegant and scalable solution because I use 15 stereo potentiometers in this mixer; and who knows, maybe I do more of these to sell if it turns out to be cheap.

The two ideas I thought are:

* To use a 5-pins modular pin header, where the tree pot legs are hosted
* To solder it nevertheless, expecting that the swaps won't be too often
The problem with the first option, is that those pin headers also wear out and the link usually becomes loose, which is even a worse problem than noisy potentiometers. A solution would be a connector intended for permanent but serviceable connections, such as screws. I know no solutions for this that are applicable to a typical potentiometer pin.

The problem with the second option, is that the potentiometers are three-legged, so they can be very difficult to de-solder: when you melted one connection, there are two other connections that are still holding it in place. I thought that maybe the board could have cutouts where the potentiomers go, and two of its legs make contact as if it was an SMD potentiometer, and the third leg doesn't make contact until you make a bridge with the solder, which would be easier to break without needing to move the potentiometer first.

Apart from these ideas, what else could I consider as a solution? Have you tried any of these ideas?

Kasper:
Here are some ideas; I would go with 1 or 3b.

1: Your idea of plugging trimpots into header seems fine. Make sure the PCB and the trimpots are fastened securely and the header shouldnt wear out.

3: solder them in and get better at removing them.
3a: Get a very large tip for your soldering iron so it can heat all 3 pins at once.
3b: Cut the pins before desoldering.
3c: Bend the legs and solder them smt not thru hole.

4: Use terminal blocks to hold the pins.

5: Make you own 'terminal blocks' aka use screws to attach the pins to the pcb.

6: Make an extra PCB just to hold trimpots.
Solder the trimpots to the PCB and make the PCB easy to swap. For example with header strip(s) connecting it to main PCB


grbk:
If it were me, I would solder wires to the pot legs and use crimped wire-to-board connectors on the ends of the wires. Heatshrink for strain relief on the wire-to-pot soldered connection.

The downside is that you have to do the crimping, which is a hassle if you don't have a crimping tool suitable for the connector system. For many (most?) connector systems you can get pre-crimped wires, however.

The upside is that if the crimps are properly done it will be very reliable, with no loosening over time like you'd get with pot legs inserted directly into a header. It's also easy to assemble if you have the crimping tool already and very easy to swap out pots if you use a decent connector system.

If you don't want to use crimped connectors, you could still solder wires onto the pot legs and insert the wires into screw terminals, which may or may not be better than putting the pot legs into screw terminals directly. At least you would get more strain relief and placement flexibility that way. You could also use IDC connectors instead of crimps.

james_s:
I doubt you'll be changing them often enough to wear out headers. You could also design the pads on the pcb to have plenty of meat and make the holes big enough that you can easily desolder pots without tearing up the board. Most of the problems I see with lifted traces are old single sided boards and fine pitch stuff.

OM222O:
easiest fix would be not using a pot at all  :-DD use an encoder on the front end, then use that to control a digital pot. when used in the voltage divider mode, they are very well matched and stable since the manufacturer targets matched resistances, rather than an absolute tolerance or tempco (digital pots are actually quite bad in terms of absolute tolerance and tempco).

If you want to avoid using an MCU, use the pots that have an increment and direction pin, which you can drive directly from the encoder, something like this:


it's easy, cheap and reliable. also allows you to simulate a multi turn pot for better accuracy for much cheaper than a multi turn pot. just keep in mind most digital pots are linear, not log. if you want a log taper, then you should pre compute a list of values or use special digital pots meant for audio applications.

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