Questions about Tappy Project

[danfrank]

Hi everyone,
A quick question about the Tappy project. I'm thinking about using it as an LFO for other projects. Does anyone know what the voltage output is of the Tappy LFO? I see the project has a 5 volt regulator so it's probably a little less than 5 volts. Has anyone measured?
Thanks.

[madbean]

The output should range from 0-5v nominally, however there is a load on it with the resistors/transistors. I have not measured it directly but you could check by first omitting R7 and R10, power up and measure. Then measure again with those resistors installed to see if it has an effect on the voltage output.

[danfrank]

Ok, thanks!
When it first came out I didn't see much use for it but now that the gears in my head are turning, it actually can be a really useful project. I need a different output voltage swing but I'm sure I can get to where I want to go with an op amp or two.
Thanks again!

[mirosol]

I just built one and it works. However. I was kinda hoping to use the LDR out as an expression pedal substitute. Quite stupid of me, but for some reason i assumed most expression inputs were just for a variable resistor. Nope. They are not. They are for variable voltage dividers, except for the Line6 "standard" which is just a variable resistor. So, the LDR out doesn't function like a pot and won't work for this purpose - at least as it is.

I tried a few things, like placing grounds for the jack sleeve, taking a 1k2 resistor from that to ring and soldering LDR output to ring and sleeve. Also added a 15k parallel with ldr limiter. Kinda works, but not quite. Like this the pedal being controlled does get the signal, but it's basically on/off with the light. Tried a number of different values too, but  no luck.

Put the project aside for a bit now. You know, to clear my head before trying more ideas on it.

Would anyone here have any ideas how to use tappy as a Roland EV-5 substitute?

[Aentons]

I have not purchased a tappy yet but I plan on it at some point in the not too distant future.

I asked some similar questions here:
https://www.madbeanpedals.com/forum/index.php?topic=32446.msg311693#msg311693

[Aentons]

http://expressionpedals.com/how-expression-pedals-work

http://expressionpedals.com/list-of-expression-pedals

This guide is fairly in depth and was very helpful for me

[Aentons]

I have not purchased a tappy yet but I plan on it at some point in the not too distant future.

I asked some similar questions here:
https://www.madbeanpedals.com/forum/index.php?topic=32446.msg311693#msg311693

I re-read my post and now realize I kind of dropped the ball on explaining what I was thinking. (Sorry Brian)

To clarify a bit:

The Tappy VCO output is pin5 of the Taplfo3 IC, and in the Tappy build doc schematic, it looks like "Bipolar output" pin8 is not grounded.

From the Taplfo3 datasheet:

"Bipolar Output
The TAPLFO2D produced a bipolar output around a bias level of 2.5V. Pin 8/BIPOLAR is now used to select this behaviour.
With the pin left unconnected, the output is bipolar around 2.5V. With the pin connected to ground, the output is unipolar from 0V up to 5V."

So my thinking was to try to get a true CV 0-5V from the VCO output which could then be used with a "floating ring" type TRS cable into TRS type expression inputs for various pedals. The floating ring is so the pedal doesn't send voltage into the Tappy. Only 0-5v is sent to the expression pedal input via the tip