Remote Volume Control/ Motorized Pot

[Judas Priest]

I got my USB scope running today and took some measurements. I don´t really trust the thing, though; what shows on the screen has about a 2 second delay. But the values of the measurements are probably correct.

To turn the pot to 0% and back up to 25% it sends a pure DC, appr. 5 volts signal to the motor. When adjusting the volume up or down it sends a square wave signal of about 3 volts.

I ordered the original ALPS pot today. Maybe I´ll get a chance to hook it up to the board next weekend and see what it does.

 

[Judas Priest]

I finally found time to try out the genuine ALPS pot with the board. I disconnected the Chinese pot and hooked up the ALPS pot with some aligator clips.

It works perfectly; on power up it goes to 0% and then to about 25%, maybe a bit less.

I am in the process of building a completely new preamp. I finished designing the circuit boards last night, and need to order the boards now. It will probably be 2 weeks before they get here, though.

Here are some pics of the remote board I ordered from Ebay:

 

[Judas Priest]

The holidays are causing a delay with my PCBs. It sucks, because I have 2 weeks of vacation now, and can´t do anything because the PCBs aren´t here yet

I listened to some rock music earlier tonight at relatively high volume, and a remote would have been VERY handy. I think I got up 20 times to adjust the volume up or down. When listening to classical music, I usually just set the volume and forget it. But with Rock, it´s a different story.

 

[gadget73]

I've given some consideration to knocking together an external remote volume control on my preamp. Probably won't go inside it just because of how its all built, but I could justify using one of the tape loops to run through an external pot. Sometimes its nice to not have to get up to change things.

 

[grindfix]

The pot on the board has 8 pins, but the 2 extra ones don´t seem to be connected to anything

Is it possible that those 2 extra pins are "loudness" taps?

 

[Judas Priest]

I guess we´ll never know. I ripped a pin out of it desoldering it from the board. So it´s junk now.

I am making progress, albeit slowly on this project. I might re do the PCBs someday, because I don´t like how a few things came out. Instead of tediously soldering all the cables from board to board and the RCA jacks, I want to use these next time:

 

[Judas Priest]

The preamp with remote is up and running now

The remote works fine; I would prefer the motor to turn a bit slower, though. But it´s ok as is.

 

[w1jim]

FYI
Here’s a remote volume control I built 10 years ago, still using it today.
https://www.audiokarma.org/forums/i...motorized-volume-control.200986/#post-2373303

 

[Judas Priest]

Cool! Thanks for sharing

 

[Judas Priest]

Man, it sure is nice being able to controll the volume without getting up!

I could get used to this

 

[rcs16]

The remote works fine; I would prefer the motor to turn a bit slower, though. But it´s ok as is.

I guess the answer to this is to PWM the control signals for the H bridge drive signals? back to coding

 

[Judas Priest]

I don´t have the time to get into that

 

[Judas Priest]

Since I didn´t like the remote that came with the board, I bought a programmable Seki Slim.

Much better