What is this type of dial/knob called?

Do you mean an optical shaft encoder?

Reply to
Andrew Holme
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It is called a pot without stops

Reply to
william coleman

Anything digital generates pulses, (counts) not voltage. Here is an example of a low cost encoder used as a manual digital pulse source available from Digikey:

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Reply to
John Popelish

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The optical encoders are more expensive than the contact types, but there are some inexpensive ones available from Digikey. $20.55

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Reply to
John Popelish

I'm trying to find the type of dial that you can turn in one direction or the other without it stopping (unlike a potentiometer). I have no idea what this part is called. Any thoughts?

Thanks.

Reply to
Kruminilius W.

I think the optical shaft encoder would do what I want, but they appear to be fairly expensive. The device I'm thinking of probably generates some type of current when the knob is turned, where the current is proportional to the rotation speed. I imagine that they're pretty cheap since I've seen them on a variety of cheap electronic devices such as the volume/digial tuning knob on radios.

or

what

Reply to
Kruminilius W.

What you are looking for is a rotational encoder, or gray code encoder. There are some low cost ($3 to $6) ones out there but some of them really suck (they ar not sturdy, go clack clack clack, and lose contact after a while). Optical encoders are much nicer, but incredibly expensive. $125 and up. You can get those even with an RS232 interface that returns relative (I moved 20 degrees) or absolute values (I am at 24 degrees).

see:

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?Ref=56293&Site=US&Cat=33096389

Low end:

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High end:

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Reply to
Matthias Melcher

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50 cent electric gear motor with a knob on the end?

Al...

Reply to
Alan Adrian

"Kruminilius W." wrote in news:kJTue.69$ snipped-for-privacy@newsreader1.level.com:

There are optical shaft encoders, or cheaper mechanical encoders like are used to adjust the display on some computer monitors. There are variable capacitors. Also popular is the metal shaft with a knob on it, which moves a dial string.

What exactly are you wanting to use this dial you are looking for for...

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Reply to
me

what

or a knob with a loose grub screw, i like the cheap 50cent dc motor idea best

Colin =^.^=

Reply to
colin

What about those wheels in a balled computer mouse??? they do what you want to do, but they are fragile.

Reply to
Ben Stephens

I don't think so. The poster appears to be looking for a device that indicates relative rotation, not absolute position. His example is of a digital volume knob on an inexpensive stereo. He's got some good answers on that - most intriguing to me is the electric motor (generator, actually, since mechanical motion is producing current) idea. I think using one of the cheaper optical encoders is probably the simplest implementation.

--
Al Brennan

"If you only knew the magnificence of the 3, 6 and 9,
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Reply to
Kitchen Man

Yep. Those are the optical encoders that have been discussed. I think the OP wants a more rugged human interface - something to be moved with the fingers?

--
Al Brennan

"If you only knew the magnificence of the 3, 6 and 9,
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Reply to
Kitchen Man

--
Unfortunately, it won\'t work since there\'s no way of determining
direction.
Reply to
John Fields

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Good luck, John

Reply to
John - KD5YI

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