OEM Radio Integration - Volume Control

**canadiandream** · 08-24-2009, 02:20 AM

Hey guys, have been searching here and google for hours. I want to take the volume control knob from my stock radio and integrate its function over usb to control the master volume on my carpc.

I checked out hacking a mouse, and other rotary encoders - was hoping to find a way to do it direct from the stock radio.

The radio volume is a potentiometer but is infinite (i.e. can keep turning it continuously, there is no set stop).

Checking it with a voltmeter it appears when you turn the dial it transiently raises the resitatance.

Has anyone ever found a way to take this output, convert to usb and have control the volume??

Thanks.,

**MGD** · 08-24-2009, 11:04 AM

If your volume knob is infinite then it's not a pot. It is an encoder. A pot can not be infinite.

**canadiandream** · 08-24-2009, 10:18 PM

True enough, it just looks like a pot ..lol. Anyways...any ideas how to convert such a device to usb?

Originally Posted by MGD

If your volume knob is infinite then it's not a pot. It is an encoder. A pot can not be infinite.

**2k1Toaster** · 08-24-2009, 10:40 PM

Well if it puts out resistance, then it doesnt matter what it is. You can use a FB and a second resistor to make a voltage divider and read in the value.