Can’t think of one like that, but generally you use a small 11 position Centralab switch and solder resistors across the positions. Search for a switch on eBay. There are many.

Chuck is right, a pot with such features would be a very custom item, read that very expensive!  The rotary switch with a string of resistors would do the same thing very cheaply.

So the first thing that came to mind was one of those decade-resistance boxes for prototype circuits:

These are generally made up of multiple 1p10t rotary switches with 10 resistors (0,1,2,3,4...9) per decade.  So you could get a 1p10t rotary switch and solder in 10 resistors corresponding to the 10 resistances you need.  But these are 2-terminal widgets and not the 3-terminal potentiometer that you may (or may not?) need.

I figure what you're really after is the mechanical detents provided by the rotary switch.  So how about modifying a 1p10t rotary switch by extending its shaft on the bottom end.  Then couple this shaft with a collar to the shaft of "any" potentiometer.

It's just that while you may find a 10-detent potentiometer, I'd think these would be specialty items so spendy and with limited choices.

Stan, what's the purpose of the shaft extension?  I'd think just using the switch as it is would fill his requirement with the resistors.  Are you thinking about the transition between points?  If so, a shorting rotary switch has make before break contacts and would probably do the trick without the mechanical trickery.

Ceramic Rotary Switch 2 pole 11 positions (Make-Before-Break). NOS. Lot of 1, eBay: 264169120324

A little more expensive, but a lot easier to get working without mechanical issues.

The boys have the best suggestion with the rotary switch but depending on the value of resistance you require you could also use a ten turn pot with a counting dial. These used to cost hundreds of dollars but I see them on eBay for 5-6 bucks. Amazing. Just search on 10 turn potentiometer.

Pete

Here's a 12 position shorting rotary switch for around $1.50 shipped.  AliExpress RS26 1 Pole Position 12 Selectable Band Rotary Channel Selector Switch

A rotary switch with a pile of resistors is technically a 2-terminal "variable resistor" which is not the same as a 3-terminal "potentiometer".  Leo may only need the functionality of a "variable resistor" but sometimes words matter. 

Anyway, make-before-break or break-before-make may not work because there's a discontinuity in resistance when changing positions.  In one case the resistance briefly goes to infinity, in the other case two adjacent values are albeit briefly shorted so the resistance at the terminals momentarily drops.  Again, it depends on the application but one can imagine situations where even a brief jump in resistance can be a deal-breaker when you expect only incremental no-hiccup changes as you increase or decrease the value.

John identified the need to use a shorting relay.  This will avoid a momentary open condition.  It will create a momentary change in overall resistance as one resistor will be bridged while two contacts are shorted.  Whether this is significant depends on the values and how this is used.

I like Stan's approach of borrowing the detent function of the switch for a ganged potentiometer.  It is fairly common to gang combinations of switches and potentiometers to a common shaft.

I would use a wafer switch with two or more wafers.  Disassemble the switch to remove one or more wafers while leaving to detent in place.  This will leave a portion of the shaft exposed on the back of the switch.  It may be flat at this point as it fits a slot in the wafer.  Fabricate a small metal bracket for the pot and include it when you reassemble the switch.   You will need to couple the two shafts.  This will allow you to use any value you require and change to a different pot if needed.  Depending on the feel you want in the detent you may need to try a few switches.

Just saw you second post Stan.  The switch approach can replace a potentiometer if you make connections to both ends of the resistor change.  This is exactly the circuit used to select the scale in simple multimeters.

Decided to ask the internet.  Mouser has potentiometers with detents for about $5.  These are available with 0, 10, 20, or 30 detents.  Here is the datasheet.

I found this at Mouser. Digikey had them too but they don't stock them and they want you to order in batches of 1200. These are 79¢ apiece for a batch of ten.

It took a while to come up with one that just might work. The idea is to use one of these to feed into an analog pin of an Arduino that does an analog to digital conversion in the range 0-1023. With the detents, I should be able to have the feel of a rotary switch to yield 11 distinct value ranges.

I thought about a rotary switch with resistors wired in but this should be much easier. I remember that my Dad had a health-kit volt ohm meter that he put together once and it was like that; one big rotary switch.

Thanks for the ideas! -- Leo

So you really did want a 3-terminal potentiometer!  Just so I understand, you're using an A/D to detect 1 of 11 positions of the potentiometer as a selector switch to choose from 11 functions or programs or whatever in the Arduino ?

stan2004 posted:

So you really did want a 3-terminal potentiometer!  Just so I understand, you're using an A/D to detect 1 of 11 positions of the potentiometer as a selector switch to choose from 11 functions or programs or whatever in the Arduino ?

That's correct. I was thinking about the station stop block (the #132) and how I might want to work out a stop block controlled by an Arduino. I wanted to be able to vary the number of times a train might pass the station without stopping. Maybe 10 times seemed like a good number. I knew it could be done with a nice panel mount potentiometer. But continuously variable just doesn't cut it when you want a small count. I wasn't even sure if a pot with detents existed other than the ones with a center detent for stereo controls. If this idea works, I may use it for precise delay timing as well.

stan2004 posted:

A rotary switch with a pile of resistors is technically a 2-terminal "variable resistor" which is not the same as a 3-terminal "potentiometer".  Leo may only need the functionality of a "variable resistor" but sometimes words matter.  

Au contraire Stan.  There's no reason in the world you can't connect to both ends of the resistor string on the switch to make it the same as a three-terminal pot, just with steps.  Words do matter, but I'm not getting your point here.

I had the same observation 

Just a note:

The Arduino map() function would let you change a pot that goes from 0 to 1023 to one that delivers values from 0 to 10....but with no detents

You probably already know that....

eddiem posted:

Just a note:

The Arduino map() function would let you change a pot that goes from 0 to 1023 to one that delivers values from 0 to 10....but with no detents

You probably already know that....

EddieM: Yep. I knew that. What I want is a way to make a 1 of 10 selection with the pot in a reliable manner. I think the stop points will give me the range of values that I can "map" to the proper selection. It's like having a rotary switch with only 3 wires and using one input pin of the Arduino. At least that's the idea.

I found a rotary switch on an Arduino ready board.  It uses a resistor ladder/voltage divider driven by 5V with the output going to an analog input on the Arduino.  This one also has an LED on each position.

It is DFRobot Analog Rotary Switch Module V1.  It is $5.40 at https://www.dfrobot.com/product-970.html The site also has a schematic and code.

Super cool with the LED's at the select position!