I'm putting together the harness described in post #6 here: http://priuschat.com/threads/anyone...pass-the-factory-navigation-speed-lock.98717/
But you don't need to read all that to understand my question I think. I've got a SPDT switch with an LED ring. Like this one: http://www.amazon.com/SMAKN-Stainle...89381990&sr=8-1&keywords=spdt+push+button+led
Basically it has two pins for powering the 12v led and one output pin whose input is selected by the button from two other pins.
For the project above we're using the button to select between two different sine wave inputs. One is essentially from the rotation of the cars wheels and varies in frequency and amplitude (between +14v and -14v). The other input is artificially generated from a 555 timer and varies between 0 an 12v at a 50% duty cycle at something like 2Hz.
So here's the challenge. I'd like the LED to indicate something when the artificial 555 input is selected. Either turn the led on or make it brighter. This project is basically a harness so I'd like to keep it that way (no complicated breadboard).
The simple thing is to pass the real signal from the tires through a rectifier to get a fairly solid 12v signal. That would probably be brighter than the artificial signal so I would see a visual difference, but it's the opposite of what I want (dim is off, bright is on).
Any suggestion?
But you don't need to read all that to understand my question I think. I've got a SPDT switch with an LED ring. Like this one: http://www.amazon.com/SMAKN-Stainle...89381990&sr=8-1&keywords=spdt+push+button+led
Basically it has two pins for powering the 12v led and one output pin whose input is selected by the button from two other pins.
For the project above we're using the button to select between two different sine wave inputs. One is essentially from the rotation of the cars wheels and varies in frequency and amplitude (between +14v and -14v). The other input is artificially generated from a 555 timer and varies between 0 an 12v at a 50% duty cycle at something like 2Hz.
So here's the challenge. I'd like the LED to indicate something when the artificial 555 input is selected. Either turn the led on or make it brighter. This project is basically a harness so I'd like to keep it that way (no complicated breadboard).
The simple thing is to pass the real signal from the tires through a rectifier to get a fairly solid 12v signal. That would probably be brighter than the artificial signal so I would see a visual difference, but it's the opposite of what I want (dim is off, bright is on).
Any suggestion?