Remote control for motor volume potentiometer

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I am going to install a motorised Alps potentiometer in my valve amp, and I wonder where I can find schematics or kits to build a remote controller. ¿Any of you have done it already? ¿maybe using the remote control from a cheap radio-control car?

I have find this two suppliers for the potentiometer so far:

www.audioelectronicsupply.com

http://www.me-au.com/alps.html

¿Do you know some suplier in Europe?

¿Any one have tried to build this circuit?:

http://www.siliconchip.com.au/cms/A_30559/article.html

Thank you
 
here you have.
The project you mentioned it's very intresting, using a PIC you can have a very high flexibility.
Otherwise you can try to use a different schematic that controls a H-Bridge after R7 in the Receiver.

HTH
Bye Fabrizio
 

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Hi,

I interest for this project too,but anyone know where to purchase complete kit with part for this remote control application?because difficult to found part for this application in my country.

And where to buy alps motorized pots?i looking for 50k alps motorized blue pots
 
If you want to run more than one pot off the remote, you will have to use stepmotoers i guess. ALPS motorised pots dont runs all that precise, so i doubt even cheaper solutions would do. If you wanna do it real cheap, you rip a couple of old matrix printers. They include a (mostly)real nice stepmotor from the sledge.

Stepmotor drivers should not cause any problems.


Magura:)
 
That sounds like a good idea. I did have some old dot printers but I've just gotten rid of them... anyway, a few small steppers isn't going to be much I don't think.

How could I go about coupling these to the steppers? The way I see it done on CNC gear is using a pulley and a timing belt, but I guess just a standard, printer like, belt would do fine here... due to the minimal amounts of force involved.

Really, my question is, how would I couple the belt to the pot?

Would I be right in thinking I should just use another pulley on the shaft of the pot? Possibly with a large ratio between the pot and stepper to increase stepping accuracy? Does anywhere make prefabricated pulleys specifically for mounting onto pots, I'd rather not have to start drilling holes in them if I don't have to.

Or am I thinking about this entirely the wrong way and I should just use something like nylon gears instead?

John
 
One stepper per pot...directly mounted on the pot.

Thats the whole point of using a stepper. Now you actually need a fairly big stepper to do it like this....thats why i suggested to rip them out of old matrix printers, since theyre a bit expensive.

If you go for steppers thats got 1.8 degree steps, you should be good to go.


Magura
 
Stepper motor controller in Elektor

The recent issue of Elektor carried the second of a two-part article on a stepper motor controller. It's quite a sophisticated controller, which uses JFETs to drive the motors. The controller has a uC at its heart, and accepts short ASCII commands over a parallel port. It can be connected to any PC and driven. IIRC, it controls up to eight motors.

I am not saying that this is the ideal stepper motor controller for a preamp, but it's probably a good starting point for someone wanting to begin playing with stepper motors. For PCBs and other stuff, I guess one can check the Elektor UK site.

Tarun
 
Will digital pots be better?

eeka chu said:
Does anyone sell moderately priced motorised potentiometers? I would like to be able to fade two or three settings at the same time, so I can't really afford to use Alps.
Are you sure you want to use rotary mechanical pots at all? When you want to handle multiple pots in step with each other, I feel mechanical solutions become very difficult and it might be better to go the Maxim/Xicor digital pot way.

And if you are serious about small gears and things for the stepper motor approach, maybe you can look at smallparts.com for a range of ... well, small parts.
Tarun
 
pingfloid said:
I am going to install a motorised Alps potentiometer in my valve amp, and I wonder where I can find schematics or kits to build a remote controller.
From my notes, I see I have found a few sources of motor pots (Xicor and other brands are less expensive than Alps). If you've decided on Alps, I guess that's that. And there are quite a few options for the remote control bit:
  • Quasar Electronics has a kit for UKP 13 or so, which includes a complete IR receiver and uC. These relays can be used to switch the motor of your pot using additional relays or transistors. The kit also includes a handset with 14 buttons. The handset does not look like a typical audio amp handset, with keys marked "1" to "14" on a plain fascia. But once you get used to pressing "5" for "volume up" and "8" for "volume down", I guess it's as good as any. The kit works only with their own supplied handset. They also have another kit (kit 3142) which has all these components plus a PCB and a set of 12 relays, for about UKP 35.
  • Michael Percy Audio used to have a kit for precisely audio volume control, for about USD 98. I didn't see it in their current catalog, but I might have missed it. The cost of the motor pot and the handset would be extra.
  • Elektor's universal remote receiver design is powerful: it can work with any industry-standard handset. But its design is brain-damaged, according to me: the receiver generates only latching outputs. This may be a good idea when you are using it to switch on and switch off lights, but for audio amps, you need momentary inputs. The only use of latching controls in audio amps are probably the "mute" button and the "tape monitor" switch. You can't control a motor pot or input selectors using latching controls. Very sad. Moreover, the designer has incorporated a debouncing delay of almost one second for each button, thus preventing you from rapidly pressing a button in quick succession. This makes it very non-intuitive to control motor pots... you sometimes fire a rapid set of up and down button presses to get the control to the level you want. If you want it in spite of all this, the kit is available from Dil-Dos for about EUR 45. Their Website is largely in Dutch (even the section which they claim is in English), but if you write to them, they reply promptly in good English. I've got quotes from them by email before. If you don't have the Elektor article which described this IR receiver kit, you may find it a bit difficult to make use of the bunch-of-parts that the kit will comprise of.
  • Milford Instruments in Leeds, England, has a remote control receiver kit which would work with any industry standard remote handset, and drive seven output pins in momentary or latching mode. (Look for "IR decoder" on this page.) This makes it very easy to interface it with any motor pot, using a few transistors. This is what the Elektor IR receiver designers should have designed in the first place, if they had put more thought into it. This is available for UKP 29.
  • Reynolds Electronics is a great place to pick up the pieces to build your own IR decoder. They have a pre-programmed uC which, when interfaced with an IR receiver/demodulator chip, can decode the button-presses on a Sony remote, and drive output pins. This is called the IR-D15, I think. The uC chip itself is about USD 8, the IR receiver/demodulator chip is about USD 4, a Sony-compatible handset is about USD 12. You can also use any universal handset with the Sony protocol settings. The outputs of the receiver uC are 14 momentary pins, one latching pin. Very easy to use to build what you want. The only reason I will not opt for the Milford kit as first preference is that this Rentron set of parts is less expensive. Otherwise both are very versatile, and the Milford kit is in fact more versatile... you can set each pin individually to be either momentary or latching.
  • There's a kit from Electronickits.com, whose specs are suspiciously similar to the one from Quasar. The full kit, including relays and handset, comes for about USD 50. The only reason I prefer the Milford or Rentron kits over the Quasar or this one, is the appearance of the handset, and its proprietary nature. (I have had handsets go bad on me, and I'm more comfortable with a kit which works with "any standard handset" or "any Sony handset" rather than "Our Own Handset". If you don't much care about this, then you may find this one or the Quasar one easier to use for your motor pot, since the relays will directly drive a motor easily. To be fair to Quasar, they sell extra handsets for about UKP 8 each.

While reading up about IR receiver kits, I realised that the most general-purpose design would
  • work with any handset type (Elektor, Milford, and within broad limits, Rentron)
  • generate either latching or momentary inputs (Milford) which should be selectable at setup time, or at least just momentary inputs (Rentron, Milford, Quasar, Electronickits)
  • work with a good-looking handset (Elektor, Milford, Rentron).
Of these, the momentary-versus-latching outputs seemed the biggest pain to me. If you want latching outputs, and your kit gives you momentary outputs, it's possible to add latch ICs. If you want momentary, and the kit gives you latching, you're in deeper trouble... it's not easy to convert latching to momentary. You'll have to catch both the leading and the trailing edge of each pulse ("latch on" and "latch off" events), and convert each edge to a short pulse. A capacitor as differentiator, followed by a monostable multivibrator, may do it, but I've yet to try it. And even then, it won't give you the behaviour of the true "momentary"-type receivers, which keep the output pin asserted as long as you keep the handset button pressed. With my cap+MMV scheme, this may or may not work, depending on how your latching-type receiver IC handles long key-presses and auto-repeat conditions. And to top it all, Elektor's one-second debouncing delay seems sheer craziness.

The Rentron and the Milford options are the ones on the top of my list.

Hope this helps.

Tarun
 
The Elektor IR receiver

UrSv said:
Elektor also published a very simple project in January 2001 called Learning RC5 decoder.
Yes, and I was so excited when I saw they'd published the design, I could hardly wait to read that article. And when I read it, I was so disappointed that I wrote an email to the Editor of the UK edition, complaining about the design. (I received a polite acknowledgement, saying "we're forwarding it to the right people". Of course, nothing came of it. :D )

They have done a good job, it appears, about supporting all the half-dozen industry standard IR remote protocols. So the pain of finding the "right" handset is gone. However, the output signals their design generates are very difficult to use. IIRC, they generate only latching outputs. Look at your typical domestic TV, DVD player, or audio system remote, and tell me how many of these pins are latching? The only ones which may be latching will be "mute", "pause", and "power on/off." All the others are either momentary (channel change, volume change, track skip in CD players) or are select-1-out-of-N. Latching outputs are used for garage door openers perhaps, but not in the living room. I don't know what thought process in those engineers led them to design a purely latching-output receiver kit.

When I compare their design with the Milford kit, I can see how much more intelligently designed the Milford kit is. For each output pin, the Milford kit allows you to set up whether it will be latching or momentary. The uC "learns" this at setup time. If the Elektor designers wanted to really build a "learning remote receiver", they should have done something like this.

Ah, well. :)

Tarun
 
Re: The Elektor IR receiver

tcpip said:

Yes, and I was so excited when I saw they'd published the design, I could hardly wait to read that article. And when I read it, I was so disappointed that I wrote an email to the Editor of the UK edition, complaining about the design. (I received a polite acknowledgement, saying "we're forwarding it to the right people". Of course, nothing came of it. :D )

They have done a good job, it appears, about supporting all the half-dozen industry standard IR remote protocols. So the pain of finding the "right" handset is gone. However, the output signals their design generates are very difficult to use. IIRC, they generate only latching outputs. Look at your typical domestic TV, DVD player, or audio system remote, and tell me how many of these pins are latching? The only ones which may be latching will be "mute", "pause", and "power on/off." All the others are either momentary (channel change, volume change, track skip in CD players) or are select-1-out-of-N. Latching outputs are used for garage door openers perhaps, but not in the living room. I don't know what thought process in those engineers led them to design a purely latching-output receiver kit.

When I compare their design with the Milford kit, I can see how much more intelligently designed the Milford kit is. For each output pin, the Milford kit allows you to set up whether it will be latching or momentary. The uC "learns" this at setup time. If the Elektor designers wanted to really build a "learning remote receiver", they should have done something like this.

Ah, well. :)

Tarun

Actually it produces a momentary voltage out for a motor driven potentiometer. It has two outputs to drive a motor driver and by learning two buttons quickly it can then use any RC5 remote using any buttons to turn the volume up or down. Really, I can't see any way that it could be any simpler than to connect the pot and nothing else. It was specifically designed for this purpose and for that it was pretty slick. Can't see why you would complain if that was the article you read. It was a most excellent implemention and I would say exactly what pingfloid wanted.
 
Re: Re: The Elektor IR receiver

UrSv said:
Actually it produces a momentary voltage out for a motor driven potentiometer. It has two outputs to drive a motor driver and by learning two buttons quickly it can then use any RC5 remote using any buttons to turn the volume up or down. Really, I can't see any way that it could be any simpler than to connect the pot and nothing else. It was specifically designed for this purpose and for that it was pretty slick.
You mean that the design you've studied has momentary outputs, not latched ones? Or is it that there's some special way to set it up such that you are getting the effect of momentary pulses even with the latching-output behaviour of the project. Sorry, I'm confused. :confused:

And do you remember any reference to the one-second debouncing? If not, then maybe we're talking about different projects altogether? (Highly unlikely, but possible).

Tarun

Edit: Maybe we are talking about different projects. The one that I remember has many output lines, not just two. And it is probably called "Universal IR receiver" not "learning receiver." I'll go home and try to dig it out.

Second edit: YES!!!! We are indeed talking of two different projects. The one you are referring to is the "Learning RC5 Control Decoder" published by Elektor in Jan 2001. The one I am talking about is the "Multi-Standard Infrared Receiver", a much more sophisticated project (support for multiple IR protocols) which was published in April 2002. :cool: My honour has been restored. :D
 
Cheap Alps Motor Pots

I've got a bunch of surplus Alps dual 100K PCB mount motor pots I will sell for $10.00 ea to all interested. The model # is 808t-100KAX2. These have a 3.6VDC motor. I've included a photo.

Just email me at jimbo149@fastermail.com. I accept Paypal so everyone will have independent record of all the transaction details. We can exchange all personal info like full names and addresses at the time of your order.


Cheers

Jimbo
 

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till said:
In case of interest in motorpots, write "ALPS 742t-10KBX2" in the mask labled "Produktsuche" and click "Los" at http://www.pollin.de/default.asp?content=welcome.html
Amazingly attractive price. I wish they had other values. I need 100K, and might have been able to manage with 50K, but 10K seems way too low. And can you please translate what they have said there about "LED"? Does the pot also have an LED provision? If yes, where can I find more info about how such LEDs need to be wired to pot? (I presume the LED is supposed to be fit into a hole in the knob?)
 
Re: Cheap Alps Motor Pots

jimbo149 said:
I've got a bunch of surplus Alps dual 100K PCB mount motor pots I will sell for $10.00 ea to all interested. The model # is 808t-100KAX2. These have a 3.6VDC motor...
What taper are these (I'm interested in a linear taper, because I can convert it to log taper by adding a 20KOhm balance pot after it, as per Rod Elliott's idea.) And does the motor take 3 to 6V or did you correctly write 3.6V? Sorry if my question seems stupid... it's just that I've only seen 5 to 6V rated motors, never 3.6V. :) And is the shaft a 6mm flatted one? That's what it seems like to me, from your photo.
 
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