Build Your Own Arcade Controls Forum
Main => Audio/Jukebox/MP3 Forum => Topic started by: UncleArgyle on August 30, 2012, 11:36:45 am
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Hi everyone,
I have a Dell USB keyboard that has a dial volume control on it. I have removed the internal components board that contains the potentiometer. I want to remotely mount the potentiometer and then wire it back to the board.
The issue is that existing potentiometer has no mounting threads. I would like to buy one at radio shack...would anyone know what specs I should look for? I didn't see any markings on the potentiometer.
I appreciate any help.
Mike.
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if it is in fact a potentiometer you can measure the resistance with an ohm meter. My first guess though is that it would be digitally controlled and not even a potentiometer.
Sent from my Desire HD
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I know very little about electronics...but I think I can measure the resistance. There are 3 leads...across which would I measure the resistance?
Is this not a potentiometer?
(http://desmond.imageshack.us/Himg145/scaled.php?server=145&filename=potentiometer.jpg&res=landing)
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Sorry, I can't see that picture, image hosting is blocked at my work. :(
Assuming it is a pot, you should be able to test the resistance easily. You would need to remove the pot from the wires, then put one multimeter lead on the middle connecter and the other lead to an outer connector. Then switch your multimeter to something like 200k ohms. When you turn your dial all the way, you should be able to turn the dial all the way and see the maximum resistance on the pot.
I have a feeling it is not a pot though....I would be willing to bet it is some sort of rotary encoder.
http://adafruit.com/products/377 (http://adafruit.com/products/377)
Can it spin forever, or does it stop. If it keeps spinning, it is some sort of rotary dial.
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Thanks Brad808 and Vigo. It does spin forever...so it looks like it is a rotary encoder/dial. I'll research on them a little and see if I can find one to suit my needs.
Appreciate the help,
Mike.
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The keyboard dial lowers the volume slider in Windows correct? You might have an easier time leaving the volume slider in Windows at full and using a potentiometer at your amplifier for your speakers.
Sent from my Desire HD
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Yeah, it lowers and raises the Windows slider. It works in hypersin and the emulators. Seemed like a good solution. I'll look into putting a Potentiometer at the amplifier like you mentioned.
Thanks,
Mike.
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Can it spin forever, or does it stop. If it keeps spinning, it is some sort of rotary dial.
For the record, some pots can spin forever. They just don't change resistance any more once they hit either rail, but you might be able to feel a light click with each revolution once you hit either limit.
Not saying that this is for sure a pot and not remotely claiming that all pots can spin forever, but some definitely can. They're all over the place on the military circuit cards I used to write test programs for.
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Can it spin forever, or does it stop. If it keeps spinning, it is some sort of rotary dial.
For the record, some pots can spin forever. They just don't change resistance any more once they hit either rail, but you might be able to feel a light click with each revolution once you hit either limit.
Not saying that this is for sure a pot and not remotely claiming that all pots can spin forever, but some definitely can. They're all over the place on the military circuit cards I used to write test programs for.
True dat. I just don't think they would ever use that kind of pot for a volume dial. I've seen weirder stuff though. :cheers:
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I'm pretty sure that is a (incremental) rotary encoder, not a potentiometer.
Just do a search on eBay and you will probably find many alternatives with threads.
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Can it spin forever, or does it stop. If it keeps spinning, it is some sort of rotary dial.
For the record, some pots can spin forever. They just don't change resistance any more once they hit either rail, but you might be able to feel a light click with each revolution once you hit either limit.
Not saying that this is for sure a pot and not remotely claiming that all pots can spin forever, but some definitely can. They're all over the place on the military circuit cards I used to write test programs for.
[threadjack] I've been looking for that type of continuos pot for a while. Most that I find just cross back to the other extreme causing a huge jump in output from high to low or versa vice. Any links available to a retailer or model number for a pot that spins continuously but maxes out at a value?
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Can it spin forever, or does it stop. If it keeps spinning, it is some sort of rotary dial.
For the record, some pots can spin forever. They just don't change resistance any more once they hit either rail, but you might be able to feel a light click with each revolution once you hit either limit.
Not saying that this is for sure a pot and not remotely claiming that all pots can spin forever, but some definitely can. They're all over the place on the military circuit cards I used to write test programs for.
[threadjack] I've been looking for that type of continuos pot for a while. Most that I find just cross back to the other extreme causing a huge jump in output from high to low or versa vice. Any links available to a retailer or model number for a pot that spins continuously but maxes out at a value?
I believe most of the 12 turn pots would do what you are looking for. They turn continuously but once they hit there max value at the high or low end they just stay there.
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Can it spin forever, or does it stop. If it keeps spinning, it is some sort of rotary dial.
For the record, some pots can spin forever. They just don't change resistance any more once they hit either rail, but you might be able to feel a light click with each revolution once you hit either limit.
Not saying that this is for sure a pot and not remotely claiming that all pots can spin forever, but some definitely can. They're all over the place on the military circuit cards I used to write test programs for.
[threadjack] I've been looking for that type of continuos pot for a while. Most that I find just cross back to the other extreme causing a huge jump in output from high to low or versa vice. Any links available to a retailer or model number for a pot that spins continuously but maxes out at a value?
I believe most of the 12 turn pots would do what you are looking for. They turn continuously but once they hit there max value at the high or low end they just stay there.
It's literally been like 15 years since I was doing that sort of work so I can't be certain, but I did a quick search on "blue trimpots" and found this link...
http://www.robotroom.com/Trimpots.html (http://www.robotroom.com/Trimpots.html)
The third one from the left in the first pic sure looks like what we used all over the place on the old naval MK45 circuit boards... I can't recall if the ones we used were made by Bourns like the ones in the pic, but other than that they look identical. His text says these are actually 25 turn multiturns... makes sense, we used them to fine tune old analog circuitry to the added precision would have been useful to us. The one in the pic is in stock at Mouser...
http://www.mouser.com/Search/Refine.aspx?Keyword=652-3296W-1-203LF (http://www.mouser.com/Search/Refine.aspx?Keyword=652-3296W-1-203LF)
At $2.50 a pop, they're a bit pricey for a pot IMO, but the 10-turn ones may be cheaper. Or maybe you can find a lot of them on ebay, or find some at a surplus store. I'm about due for another Mouser order, if they were fifty cents a piece I'd pick up a dozen but as it is I might just nab a couple.
I've got lots of pots lying around but since we've been discussing it I'm missing those old trimmers. :cheers:
Edit: be sure to check the second page of that first link I sent, it shows cutaways of single turn and multiturn trimpots and explains how they work. It even shows a gap in the teeth of the rotating wheel inside a multiturn trimmer that prevents the worm screw from pushing it past one of the rails. Neat. Now, it's entirely possible that a different brand of trimmer might just have continuous teeth on that wheel in which case it would keep turning and WOULD pop back to the other extreme resistance, so a little experimentation with whatever brand you end up with might be a good idea. I checked ebay, there are lots of lots little blue trimmers on there, but most are not Bourns if that matters to ya. I may snag a cheap lot just to see what I end up with.
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Thanks for running that down, wasn't what I was hoping for though. Problem with those multi-turns is that it can take me twelve revolutions to get back to center, I need a single turn pot on a slip clutch, so you get full range of variance in a single turn with the capability to continue to turn past that. Once you reverse direction you only have a single rotation before you're maxed the other way. Well, to be honest what I really need is a rotary encoder (of which I have several) but I need to wire it where a pot used to go so it raises all kinds of issues since the board can't handle the encoder. I'm sure something will turn up, just need to keep searching. Thanks tho!
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Thanks for running that down, wasn't what I was hoping for though. Problem with those multi-turns is that it can take me twelve revolutions to get back to center, I need a single turn pot on a slip clutch, so you get full range of variance in a single turn with the capability to continue to turn past that. Once you reverse direction you only have a single rotation before you're maxed the other way. Well, to be honest what I really need is a rotary encoder (of which I have several) but I need to wire it where a pot used to go so it raises all kinds of issues since the board can't handle the encoder. I'm sure something will turn up, just need to keep searching. Thanks tho!
Hmm, yeah for that one I got no ideas. ;D Except for maybe trying to make your own out of a regular single turn, but offhand I'm not sure how to pull that off... :lol
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u used a griffen powermate for my volume control , excellent looking , runs off usb , i glued mine and its holding no worries so maybe even glue
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i second that...the griffen powermate is awesome for volume and other functions... :applaud:
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yeh the press in long and short and press in right and left can be mapped to do any function , pretty handy