Dual Latching/Momentary Switch

[PurpleTheory]

Hey guys,

I want to make a dual latching/momentary stomp switch using a single momentary switch and a toggle to choose between latching/momentary. Tone God's "Wicked Switches" article seems like a good candidate to make this work.

http://tech.thetonegod.com/switches/switches.html

I thought maybe I could combine "Momentary with NAND Gates" for the latching function and "Toggle with NAND Gates" for the momentary function. I wondering if anyone has any advice on the best way to approach this...
Should I build 1 of each and have a toggle that switches the V+ or maybe build the first section of the circuits and have the toggle between them a single 4066?... any ideas? 

Thanks!
Matt

[armdnrdy]

I just designed some pretty extensive switching for a BBD tester, (more on that later) and what worked on paper didn't necessarily work on my breadboard.

Also, I had a problem with the .01uf cap in the de-bouncing circuit for the momentary switch. It was controlling a flip flop that wasn't working consistently. I changed it to a .1uf and was good to go!

Breadboard!

[armdnrdy]

I think you can do this by using the SPST toggle to switch the control signal back and forth between the nand gates and directly to the 4066.

[cpm]

i use the "dual" action with an 8 pin PIC, so a short push is latching and a long one is momentary. From the pic output you can drive CMOS gates, relays, etc
It involves programming and having the setup to program the chip, but saves a lot of board space from driscrete logic
And you can easily adapt it to drive dual coil relays, fancy blinking leds, etc

[PurpleTheory]

Oh man, CPM, I really appreciate the suggestion, but that sounds beyond my capabilities as I am still a novice 

Armdnrdy, is the control signal the V+, and re-route it using the spst toggle?

Thanks guys!
Matt

[armdnrdy]

I had to look at it a bit more. I'll whip you up a schematic.

[armdnrdy]

Here you go.

http://www.aronnelson.com/gallery/main.php/v/diyuser/Switching+momentary-latching.pdf.html

The momentary switch (SW1) in conjunction with the flip flop acts like a SPST on/off switch operating the 4066 control. When you flip the SPDT switch, (SW2) you operate the 4066 control with the momentary switch. (SW1)

[PurpleTheory]

Dude! Thank you so much, I owe you a beer, I'll let you know how it goes 

Thanks again!
Matt

[armdnrdy]

Thanks. I'll take a Corona!

There is one thing about this circuit that I didn't mention. When you first power it up, the 4013 will come on in the opposite state that it was in when you powered it down.

The 4013 reacts to a "high" signal to change states. When you power it up Q1 will send IC1 a high signal changing the flip flop's state.

With that being said, I don't see an issue with this occurring in this type of application. It's not like the drummer clicks his sticks, 1, 2, 3, 4 and you push the power button on as you hit the first chord.

Basically, when you power it up you might have to hit the momentary switch to disengage the effect.