One power source two different ground

[PRR]

> No doesn't work LDR's never get to zero volume hence the need for two.

Did you try exactly what I drew for you?

> LDR's never get to zero volume

No; but if the LED gets bright the LDR should go below 1K. (The Morley plan suggests 400-850.)

1K load on 47K is 48:1 attenuation, over 33dB, a BIG drop in volume.

> cirtuit is why theres two LED's one on one off and one on all the time

It's quite curious. LDR1 seems to shift only from 2K (one LED at 0.5mA) to 800 (2 LEDs at 0.5mA/each). I wonder if there is a typo in the resistor values. Or if L1 is more distant than L3.

again: SIMPLIFY! You don't need 0%-100% action for a first try, 5%-90% would be fine.

[clydeshere]

 I don't want 5% to 90 % doesnt make for a pedal I want to build or use. LOL I knew throwing the LDR schematic on this would just complicate this thread. And yes the first thing i tried was one LDR with allot of different resistors on it and was never even close to 5% volume.

[jasperoosthoek]

So this is what you can do.



The 2n3904 is the original transistor in the proximity circuit. All you need to do is cut the direct connection to the 9 volts supply and add a 68 ohms resistor between the  transistors collector and the 9 volts supply. This extra resistor will not change the working of the original LED in any way.

But this resistor allows you to add a pnp transistor (2n3906) transistor to power a second LED. The  total current of the two LEDs will be fixed: If the left one goes up the right one goes down. The extra trimpot allows you to dial in the total current through the two LEDs.  This arrangement allows a total current of 20mA which will probably be more than enough.

Good luck!

[clydeshere]

WOO HOO cant thank you enough I'm gonna try to build this today. I'm still trying to cobble together a schematic for this but my vista infected computer wont run DIY layout 2 so I'm trying something else.

[clydeshere]

Nice works great no volume drop that I can detect.    Thanks so much it's a little choppy on the swelling but I think it can be adjusted. I will really try to get a whole schematic up but with thanksgiving and everything who knows.

Oh bye the way the 1 k pot on that circuit it seems like it just needs to be up all the way but im going to try different colors of led's sometimes makes a difference.

[jasperoosthoek]

Great! I knew it would work but I couldn't predict if it was going to be completely smooth. You can increase the current of the second LED by decreasing the 68 ohms resistor. But not all LEDs might handle big current. I think that a 56 ohms or even a 47 ohms resistor will probably still work fine and will increase your range to around 20mA. The current of the right LED can be measured by the voltage across the 68R resistor, just divide by 68. Make sure you turn off the first by touching the antenna.

Another solution to make it more stable is to connect a few diodes (pointing down) between the 9 volts supply and the top part of the 1k trimpot. That will also increase the range and make it more stable.

The choppyness of the swelling might be solved by adding a little resistor parallel to the left LED. Try maybe a 1k or so. No guarantees but a simple thing to try.

[clydeshere]

Great I'll try to work on it today and post a video but thanksgiving BS going on.

[jasperoosthoek]

I didn't realize that  . People here are preparing for Sinterklaas http://en.wikipedia.org/wiki/Sinterklaas