Idea

[pedalman]

I want to build a tremolo but that's where the fun only begins. I want it to also have a momentary switch so if its not on I can tap it for little small fills that have trails and get back to the other playing. Can this be done ? Any ideas would be helpful

[DutchMF]

I guess it would be possible, i'll give it some thought and get back to you. You would at least need a normally-closed 2PDT or 3PDT if you want a LED. Hooking two switches in parrallel was my first thought, but that wouldn't work, as the second switch would keep the effect input connected to ground.........

Paul

[pedalman]

I think this will just be a momentary trem with trails. If I need a "All-ON" I could always make a standard one. This should simplify the build

[gtr2]

It would be easy to do with a micro controller and relay...

[raulduke]

Do you mean you want the tremolo effect to fade out over time when you take your foot of the momentary switch?

Or do you just want a momentary tremolo effect (ie. effect engages when you have your foot on the switch)?

1st option will be quite difficult.

2nd option will be easy as pie (just build your tremolo of choice and use a momentary, rather than latching, 3PDT bypass switch).

[stecykmi]

what do you mean by "trails"?

[rullywowr]

It would be easy to do with a micro controller and relay...

This.  It could be done easily with an ATtiny85 (or PIC) which works a relay.  A knob would control the amount of time it supposed to be engaged and a single tap of your foot on the momentary would activate the effect for the desired amount of time.

[pedalman]

Do you mean you want the tremolo effect to fade out over time when you take your foot of the momentary switch

Yes, this is what I was after

[RobA]

With an MCU, there are several ways you could do this. I would want a momentary to fade in or out the tremolo depth and or speed. That would point towards using an always on buffer with the trem circuit after the buffer.

I've just got back a proto PCB from OSH that is pretty much designed for this type of thing. It uses an ATTiny84 so it can have 16-bit PWM. I can look into setting up this kind of thing with it after I get the thing built. It's third on my list of PCB's though, so it'll take a couple of days.

[midwayfair]

You could make an LFO that can be turned on by an envelope circuit. Use a normally off momentary and when you switch it, your guitar signal passes through a rectifier and increases the depth control. The simplest way woukd be to use a really good optocoupler [I suggest the H11F1 because of its speed, price, and low on resistance] with very low on resistance. Feed your guitar signal through the rectifier to turn on an LED. Put the LRD in series with the depth control's point of contact with the variable resistance element. When you play, your guitar signal drops the resistance into the depth control as long as you keep playing and the momentary is held. The decay resistor/capacitor combination in the rectifier keeps the LED on for a set amount of time ... You could easily get a couple seconds out of it.

I think you could also do it that you block the LFO's voltage source with the envelope control, but then you run into a problem where you need to know whether the LFO can start running within a handful of milliseconds.

The main concern is that you want to make sure that whatever is controlling the volume of the dry path is fully loud when the depth pot is blocked. So if you use the Tremulus Lune's LFO, you have to arrange the dry path so that the LDR sends signal to ground rather than is in series with the signal path ... Otherwise, when the depth drops, the LDR goes dark, and your signal cuts out. Also, you might have to rejigger the depth control.

I'm on a mobile, so apologies if some of this is unclear.

[pedalman]

With an MCU, there are several ways you could do this. I would want a momentary to fade in or out the tremolo depth and or speed. That would point towards using an always on buffer with the trem circuit after the buffer.

I've just got back a proto PCB from OSH that is pretty much designed for this type of thing. It uses an ATTiny84 so it can have 16-bit PWM. I can look into setting up this kind of thing with it after I get the thing built. It's third on my list of PCB's though, so it'll take a couple of days.

Keep me posted, this sounds very interesting