Remote switching

[propadog]

Hi, all.

I think this is appropriate for this area. If not, can someone toss it where it is? Thanks!

Background:

I'm building a new rig, and I intend racking all my fx. The rack will include the preamp and amp. I want to reduce long cable runs that attract noise, and me tripping over them (a more likely scenario). In addition, I will be adding on an FM wireless connection from guitar to rack, being between 76 and 86 MHz.

They boards will be "naked" inside the housing, connected to power and switching inside the housing, appropriate pots on the front of the housing, and the input/outputs to a patch panel on the back (prob 1/8th connectors) that allows order of effect adjustment- certainly in the first incarnation. i.e all cards without boxes inside the one case.

I freely admit that I am pushing the limits of my knowledge with this way beyond where Iv'e been before!

My Questions:

1. I was considering connecting the wah and volume pedals back to the rack. To me the obvious answer is in my right hand - half of the mechanism used to control a computer mouse. It could be optical or the old fashioned ball type, so long as it recognises and sends movement in one plane.

Q- has anyone looked at this before, and what did they come up with at the "other" end to accept the impulses and convert it to something fx recognisable? I did a search here without joy, but I may not have been searching for the right thing.

2. Any opinions, given the fx cards output, whether I'll need to do any shielding of cards?

3. Was their any movement forwards on RG's Remote Footswitch Board (which I found as remoteftsw.pdf)? I seems to fit a lot of my needs, but there's no actual values for any of the bits that I could see, or an actual PCB layout to make.

4. RG also has an ebook on PCB design, but I've been unable to raise him. Can someone give him a nudge for me! ;-)

Cheers,

The Propadog.

[R.G.]

. I was considering connecting the wah and volume pedals back to the rack. To me the obvious answer is in my right hand - half of the mechanism used to control a computer mouse. It could be optical or the old fashioned ball type, so long as it recognises and sends movement in one plane.

Q- has anyone looked at this before, and what did they come up with at the "other" end to accept the impulses and convert it to something fx recognisable? I did a search here without joy, but I may not have been searching for the right thing.

The simplest thing to do is to run low voltage DC back to the rack, for instance 0-5V or 0-9V and do all of the work at the rack. Another thing that I don't think has been properly explored is using model plane R/C servos to actually turn a pot shaft remotely based on a pot at a transmitter.

2. Any opinions, given the fx cards output, whether I'll need to do any shielding of cards?

Likely no. Shield the I/O leads and star-ground the boards.

3. Was their any movement forwards on RG's Remote Footswitch Board (which I found as remoteftsw.pdf)? I seems to fit a lot of my needs, but there's no actual values for any of the bits that I could see, or an actual PCB layout to make.

Yeah, I kinda put that out to see if anyone would pick it up. It's  based on a system I built for a friend, but not exact.

4. RG also has an ebook on PCB design, but I've been unable to raise him. Can someone give him a nudge for me! ;-)

It's not an ebook, it's hardcopy only. I did that deliberately because once it was available in softcopy, it would be copied everywhere. It's being reprinted now.

[propadog]

Thanks, R.G.

Q- has anyone looked at this before, and what did they come up with at the "other" end to accept the impulses and convert it to something fx recognisable? I did a search here without joy, but I may not have been searching for the right thing.

The simplest thing to do is to run low voltage DC back to the rack, for instance 0-5V or 0-9V and do all of the work at the rack. Another thing that I don't think has been properly explored is using model plane R/C servos to actually turn a pot shaft remotely based on a pot at a transmitter.

I'm looking at having the actual vol and wah FX inside the rack, and having only the pot or equiv out with the pedal. Would the voltage drop over distance be a problem, or is it a case of the "other end" merely reconising that there is a difference in what's coming through? I guess it depends on the circuit really...

The servo idea is interesting.... Back soon with that one.

3. Was their any movement forwards on RG's Remote Footswitch Board (which I found as remoteftsw.pdf)? I seems to fit a lot of my needs, but there's no actual values for any of the bits that I could see, or an actual PCB layout to make.

Yeah, I kinda put that out to see if anyone would pick it up. It's  based on a system I built for a friend, but not exact.

I'm picking it up! :-) Is there any way I could coerce you into sharing your notes?

4. RG also has an ebook on PCB design, but I've been unable to raise him. Can someone give him a nudge for me! ;-)

It's not an ebook, it's hardcopy only. I did that deliberately because once it was available in softcopy, it would be copied everywhere. It's being reprinted now.

You've got one sale already! Keep me in mind. :-)

[propadog]

Hi, all.

I've found a great resource for remote yet still wired controlling of switches, pots and other electrical devices. And when you think about it, it's probably the closest we will ever get to remote control of racked fx.

Try your local model railroad group...

Seriously, think about it. Underneath the paper mache diarama there is some quite elaborate controlling happening!

Cheers,

The Propadog.

[GibsonGM]

I haven't done any remote audio work like you're proposing, prop, but if you put the wah pot offboard a great distance, it seems you may get some tone sucking from the long cable run.   Correct me if I'm wrong, but the signal path does go thru the pot, doesn't it?  Maybe using a remote pot to control an optoisolator inside the rack would work well as in one of the "scratchy pot mods" we've all seen.  That way, voltage is very easy to control over long runs since you're only controlling an LED - set & forget.
Great idea! 

[propadog]

Correct me if I'm wrong, but the signal path does go thru the pot, doesn't it?  Maybe using a remote pot to control an optoisolator inside the rack would work well as in one of the "scratchy pot mods" we've all seen.  That way, voltage is very easy to control over long runs since you're only controlling an LED - set & forget.

Really the ultimate goal is I want all the work happening inside the rack, and just the barest minimum of the controlling side out on stage. I really don't want any of the actual effect leaving the rack.

Effectively, you could even have a no name pedal, but with (say) a cry-baby board in the rack, or even switch between wahs, or even add an pedal to any effect that has a pot in it somewhere that could be remotely addressed.

But back to basics first- settling on a controlling concept.