Let's design a tap tempo tremolo.

[.Mike]

has anyone suggested using this new TAPLFO thing to do phaser, wah, and other mods?

I'm sure it would be easy enough to incorporate it into a twin-t wah, like the Colorsound Inductorless. In fact, R.G. suggests it in his Technology of Wah Pedals article.



Mike

[Taylor]

Yep, and a little bit higher on that same page RG has a remote wah schematic that would let you control a regular inductor wah using the TAPLFO with an optocoupler as well. A vibe circuit like the Neovibe would also be quite doable since it's already optical.

[aziltz]

Taylor, is there a schematic of the full Tap Trem circuit posted?

[Taylor]

Yep:

http://www.aronnelson.com/gallery/main.php/v/Taylor/

[UKToecutter]

Quick question re: pot orientation.

Should the pot wipe from 0v - 5v in a clockwise direction?

Andy

[Taylor]

Yes, counterclockwise is 0v.

[markusw]

I would like to reset the phase of the LFO when pushing the bypass switch. What would be the easiest way to generate a negative going pulse to reset the LFO by using one pole of a 3PDT foot switch?

Thanks for your help in advance! 
Ah, and sorry if this was already discussed....

Peace,

Markus

[boogietube]

I'm wondering why I can't download the PDF'S from the gallery? I can't download any PDF'S from the gallery for that matter...

Could someone e-mail me it?

Please?

seandavidharris@gmail.com

Thanks in advance...

[boogietube]

Aahhhhh...GOT IT NOW.........

[Taylor]

Yeah, the PDFs are akind of hidden on the page...

I would like to reset the phase of the LFO when pushing the bypass switch. What would be the easiest way to generate a negative going pulse to reset the LFO by using one pole of a 3PDT foot switch?

Thanks for your help in advance! 
Ah, and sorry if this was already discussed....

Peace,

Markus

Hey Marcus, somehow I didn't see this when you posted it (I do think I was moving my house at the time, guess that explains it).

You'd have to build a logic circuit to turn a stage change into a pulse. I'm not positive how to do that honestly, as I'm just learning logic myself. I will be getting my copy of The Art of Electronics in a day or 2 hopefully, and if you're still interested in this, post again in a few days to remind me and perhaps I'll have an answer for you.

But, did you know that tapping the tempo switch once resets the oscillator phase? It's not quite as elegant, but basically you can do what you want by hitting both the bypass and tempo switch when turning on the effect.

[JKowalski]

I would like to reset the phase of the LFO when pushing the bypass switch. What would be the easiest way to generate a negative going pulse to reset the LFO by using one pole of a 3PDT foot switch?

Thanks for your help in advance!  
Ah, and sorry if this was already discussed....

Peace,

Markus

It's really easy. You don't need any extra components. The "negative going pulse" needed to switch inputs on the chip just means that whenever the voltage on that pin goes to zero after being at 5V then it will trigger. If you put a square wave on the pin, it will trigger at every time the square wave transitions from 5v to 0v. I assume you don't care about the bypass being reset when the effect is turned OFF, only when it is turned ON, so if you hook up an extra pole on your bypass switch (you can use the LED switch pole on a 3PDT for this too, serves two purposes, but remember if you do this to use the 5V supply for the LED not the 9V) to put a 5V on the pin when the effect is OFF and GND on the pin when ON, turning the effect on will trigger the 5v->0v negative "pulse" and reset the phase.

EDIT: ah sorry I'll work it out for you tomorrow morning. This wont work since you need to be able to use the tap tempo button along with it.  

I'll give you a hint though, to generate a  pulse use a decoupling capacitor to block the DC component of the square wave "state change" from the switch.

[JKowalski]

In the interest of keeping it simple here is something to try, rendered in lovely MS paint-o-vision:



Gives a negative pulse whenever you

A: switch the SPDT switch to 5V

B: Hit the SPST momentary

Also incorporates the "effect on" LED.

The capacitor and the resistor to ground determines the length of the pulse. The MOSFET drain resistor can be almost anything, maybe 100k

[Taylor]

Hey that's very slick. I simmed it and it works just as you say.

[Barcode80]

Just a tip, if you want to save outboard wiring, the outside lugs connect to +5v and ground, so you can actually wire lug 3 and lug 1 of any of the pots (except the multiplier pot) to the board and tie them to the corresponding lugs on all the pots. I did this and it worked great and really used a lot less wire.

[Jaicen_solo]

Ok, maybe this has already been answered, but I can't see it anywhere in this thread, and this thread is LONG!
I was just wondering if it is possible that the tap tempo could control the repeats on something like the PT80 delay?
I'd also like to have a dedicated square wave output for 16ths  so that I can control a vanishing point.
Is any of this possible?

[Barcode80]

this tap tempo can't be used to control a PT80, but there is a kit in Aron's store (link at the top of the forum page) called Taptation which can add tap tempo to any PT2399 based circuit. I'm not sure about the square wave output, but thought I'd answer the question I knew

[spargo]

Barcode80,

Just to clarify, you can connect all of the #1 lugs and all of the #3 lugs on the pots together and just connect to one of the pot contacts on the board, with the exception of the multiplier pot?  I'm assuming an external volume pot is excluded from this as well?

[Barcode80]

correct, I was referring to the standard build with the internal trim for volume. The same does not apply to that pot.

[Barcode80]

Quick question, is the momentary switch for the tap supposed to be normally open or normally closed? I'm using a normally open, and it seems the tap tempo is running off the travel back up from my tap instead of the actual tap. Thoughts?

[Taylor]

It should be normally open, and closing the switch grounds the tap pin. Are you sure your switch is NO?