Remote Volume Pedal with LED/LDR combo?

(1/2) > >>

DiamondDog:
Hi,

Before you ask, yes, I have searched- such as this :D

I have a remote wah, using the circuit from RG's Technology of Wah pedals (thanks, RG!) What I would like to do now is apply the same LED/LDR concept to a volume pedal.

My breadboard is occupied with a disemboweled Rat at the moment so I can't start prototyping yet. (Only one breadboard? Yeah, I know...  :-\ ) What I would like to do is ask some questions so I'm facing the right direction when it becomes vacant again.

0. I'm not into reinventing the wheel. Does anyone already have such a circuit?

1. I'm seeing as a basic building block the Anderton volume pedal descratcher, and replacing the the pot resistance a LDR + resistor. The pedal end will be what's needed to drive the LED at the LDR end. Yes, lift-and-drop the concept from the remote wah circuit.

Is this too simplistic an approach? What Obvious Thing have I overlooked?

2. While I'm doing that, is it possible to sub a lm13600 for the CA3080/071 combination without major headaches?

That should do for now...  ;)

R.G.:
Quote

0. I'm not into reinventing the wheel. Does anyone already have such a circuit?
Yes, the Anderton volume pedal de-scratcher.
Quote

1. I'm seeing as a basic building block the Anderton volume pedal descratcher, and replacing the the pot resistance a LDR + resistor. The pedal end will be what's needed to drive the LED at the LDR end. Yes, lift-and-drop the concept from the remote wah circuit.
I'm confused. Why do you need to do anything else with the pedal end other than what Craig did? Is there a good reason I just can't see?

Quote

2. While I'm doing that, is it possible to sub a lm13600 for the CA3080/071 combination without major headaches?
Y es. That's what the darlington buffer on the LM13600/13700 is for.

By the way, the LM13700 has a fixed bias for the darlington buffer, the LM13600 has a buffer bias that's proportional to the Iabc. The 13600 is therefore good for low power applications as the buffer does not burn constant power. The LM13700 is better for audio, as the buffer does not telegraph the change in amplifier bias, so has lower thump and control noise.

DiamondDog:
Quote from: R.G. on July 10, 2008, 07:56:51 PM


Quote

1. I'm seeing as a basic building block the Anderton volume pedal descratcher, and replacing the the pot resistance a LDR + resistor. The pedal end will be what's needed to drive the LED at the LDR end. Yes, lift-and-drop the concept from the remote wah circuit.
I'm confused. Why do you need to do anything else with the pedal end other than what Craig did? Is there a good reason I just can't see?


Yes. It will integrate into the system I already have. There is a distance issue involved. Anyway - looks like I'm on my own!

Thanks for the reply, RG- I appreciate it!  :D


Ben N:
I think RG's point is that the VPR already allows you to isolate the pedal from the signal--that is what the CA3080 or whatever does. You can just put the VPR in your signal chain where you want it and run a cord out to the pedal, and there you are (or as the Queen's subjects like to say, "Bob's your uncle"). LED/LDR is another way to possibly accomplish the same purpose, assuming you can get the right range of resistance out your LDR, but you need one or the other, not both. Trying to sub an LDR for the pot in the VPR is adding unnecessary complexity for zero benefit.

R.G.:
Thanks, Ben! I just gotta get back into those "English as a second language" courses!  :icon_biggrin:

That is what I meant. I always saw that one could remote the pedal from the controlled amplifier. In fact, that is one of the chief virtues of the volume pedal circuit.

Navigation

[0] Message Index

[#] Next page