3pdt stomps - I'm done! alternatives - opto or relay bypass?

[Tkrain42]

Yes, I looked at it earlier... unfortunately, I didn't have that particular part number handy when I was talking to Don (the engineer).  I'll show it to him tomorrow, if he happens to come by the plant, but I went ahead and pulled the trigger on the DG413, since I found them at FutureElectronics for about 1.25...   Since I'd need 3 of the H11F1 to build one switch... not to mention more hardware, I'm personally going to run with the DG413.

[cooder]

This is an interesting thread, will be interesting to see all the different alternatives and how they work out.
I'm digging relay switching at present.

[blearyeyes]

In their favour, churches, most awesome natural room reverb ever.

Many great acoustic designs for choirs and such in church buildings. Had the pleasure of using a circular building designed for worship as a rehearsal / youth center many years ago... what a joy to play a 4x12 into a great reverberant room... 

end hijack/

[blearyeyes]

I used boss pedals exclusively throughout my career and didn't even think about the momentary switching until building my own. But i am very interested in finding the best alternative.

[john_p_wi]

Looking at the DG413 data sheet, it appears that this particular switch uses a low level logic signal, 2 volt max for switching which will need to be taken into account.

http://www.vishay.com/docs/70050/dg411.pdf

Regarding the H11F1, last night I looked at one with the scope and signal generator.  Biasing the led to 20 ma, it tested 80 ohms on resistance - don't remember the off.  I threw a 20 v p-p signal (sine) with a wavetek signal generator and measured a 8 mv out voltage in series switch "off" configuration with a 1 meg resistor to ground.  The signal retained it's integrity, without distortion at the high p-p range which is important to me as a tube amp builder.

IF I was looking into a switching system at the very front, IMHO it would be hard to beat a mechanical relay series configured followed with an H11F1 in a shunt configuration to mitigate the pops.  The mechanical relay will avoid the tone roll off mentioned above by having minimal resistance and capacitance in the series configuration and the H11F1 with its' faster response time would then minimize any relay pop.

[Justus]

So there are a few opinions in this thread about the Alpha DPDT "light click" vs. a SPST momentary "no click" switch...   does anyone know of any video review/comparisons of different effects pedal switching possibilities? 

[Tkrain42]

Looking at the DG413 data sheet, it appears that this particular switch uses a low level logic signal, 2 volt max for switching which will need to be taken into account.

Actually, it's a 5 volt switch... that's how digital logic works, for this board anything under the 0.8 volts is "Low", anything over 2.4 volts is "High".  For my own design (I've got 7 stomps in one box) I'm going to use an Arduino to sense the momentary switches and toggle the appropriate digital switches.  With this setup, one Arduino can control all 7, and I can even make "setups" (i.e. when this distortion is engaged, turn the other 3 off, or pushing this button engages this configuration, etc).   It's something I've wanted to do for a while anyways, and getting completely pissed off at those godforsaken blue 3pdt switches has gotten me off my keaster to do something about it.   
Parts and PCBs are ordered...  I'll know how it all works in a week or two. 

[Justus]

Anyone know of any articles on what is needed to be done with the microcontroller, relay and optical chip to make a silent, mute-while-switch deal?  I'd like to learn and then build my own...  mostly for an exercise in learning and building, but also because I want a silent switch and still add in some of the other cool things that can be found on some 3PDT switch boards, such as power filtering, trim on the LED to adjust brightness, etc.

From what I gather, TH-Customs' Uber-Switch does this, and even though there's a schematic that I've looked over a lot, the process isn't explained in the BOM.

Edit:  Wow, if it was a snake it would have bit me.  Found my answer: http://diy.thcustom.com/switching-relay-true-bypass-circuits-using-a-microcontroller/

[john_p_wi]

An easy overview of an approach is as follows:

The relay is in series with the signal and is used as a "series" switch. 
The opto follows the the relay and is a "shunt" to ground.

The micro controller would:
1) Energize the opto shunting the signal to ground.
2) Dwell enough time for the opto to activate
3) Energize / switch the relay
4) After the switching time of the armature, de energize the opto.

5) have good relay power isolation to avoid the inductive pop passing through the signal circuit power supply.

Keeping all of this around 20 ms will make for an uninterrupted noiseless switch.

[micromegas]

Anyone know of any articles on what is needed to be done with the microcontroller, relay and optical chip to make a silent, mute-while-switch deal?  I'd like to learn and then build my own...  mostly for an exercise in learning and building, but also because I want a silent switch and still add in some of the other cool things that can be found on some 3PDT switch boards, such as power filtering, trim on the LED to adjust brightness, etc.

From what I gather, TH-Customs' Uber-Switch does this, and even though there's a schematic that I've looked over a lot, the process isn't explained in the BOM.

Edit:  Wow, if it was a snake it would have bit me.  Found my answer: http://diy.thcustom.com/switching-relay-true-bypass-circuits-using-a-microcontroller/

you can check these articles too:
http://stompville.co.uk/?p=260
http://stompville.co.uk/?p=423
Very descriptive and with links to debouncing routines

[Justus]

Anyone know of any articles on what is needed to be done with the microcontroller, relay and optical chip to make a silent, mute-while-switch deal?  I'd like to learn and then build my own...  mostly for an exercise in learning and building, but also because I want a silent switch and still add in some of the other cool things that can be found on some 3PDT switch boards, such as power filtering, trim on the LED to adjust brightness, etc.

From what I gather, TH-Customs' Uber-Switch does this, and even though there's a schematic that I've looked over a lot, the process isn't explained in the BOM.

Edit:  Wow, if it was a snake it would have bit me.  Found my answer: http://diy.thcustom.com/switching-relay-true-bypass-circuits-using-a-microcontroller/

you can check these articles too:
http://stompville.co.uk/?p=260
http://stompville.co.uk/?p=423
Very descriptive and with links to debouncing routines

Awesome, thank you!

[chromesphere]

I get my H11F1 from a local dealer. You could contact your nearest dealer, they usually have easy acces to those.

Maybe you could pm Paul (Cromesphere). I think it might be a good addition to his shop and make opto-fets something accesible for all the guys in the Pacific (and for us, Paul shipping rate is ridiculously low!).

I've been using Josh's Optotrons for a while and do not see myself going back to 3pdts.
However, I would like to try Rullywow's too, they have a smaller footprint and the TP222G is a little better than the H11F1.

I can get the h11f1 but not the tp222g.  Ill request a quote from a few of my suppliers for the h11f1 and throw a few on the store for anyone needing them in my neck of the woods.  Cheers.

[the3secondrule]

Let me know when you get them in Paul, I'll probably take 10, depending on price

[GrindCustoms]

Well... we are currently offering them in our groupbuy at 1$ each, 3.50$ shipping worldwide, no quantity limit....

[chromesphere]

That's a good price!  I don't think I would be able to beat that but I will let you know what I can scratch up.