Need Help: Manual Trigger, 0-5v Out

The doodle kinda says it all lol…
(maybe not - I think what im looking for is a Trigger to send out 0-5v)
How do?

Doepfer Manual Gate

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If you want to limit the voltage you need a voltage divider. So for a nominal 5V gate from a 12V supply you’d have a couple of load resistors R1 and R2 across the positive busbar and the ground, with R1 amounting to 5/12ths of R1+R2. Thus assuming high impedance on the gate input (which is normal for analogue modular synthesis) the potential difference (ie voltage) across R1 will be 5V. Have the button wired so that until it’s pressed it breaks the connection between R2 and the +12V busbar, so the gate input will be pulled to ground through R1.

Caution: I’m a software guy, not an expert in electronics.

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I think I should re-word what it is -

Not a Gate - just a Trigger -

Push a button it send out 0-5v yada yada.
lol.

So not really a gate at all i guess, since there will be no input. (derp on my part)

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I assume what you want is for the user to press a button and this device magically makes 5V appear at the gate input of the module you have patched into. When the user lets go of the button the voltage returns to zero. That’s what I described: a voltage divider that only operates for as long as the button stays pressed.

The term “trigger” has been used for different meanings over the years so I’m avoiding that terminology. But in modern usage it often refers to a very brief pulse that rapidly returns to 0V. Is that what you want?

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It sounds to me like what you dudes are describing is a gated variable voltage source. That would look something like this:


I’m not seeing what the intended use is. If you use this for a v/octave pitch or for example a vca manual volume control, the pitch/volume will always return to the 0v value when the switch isn’t closed. If you’re using it to trigger a gate, the gate may not open if the attenuating pot is set too low. That may be exactly what you have in mind though, @d42kn355. Does that help?

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I believe this is exactly what im looking for ^ :smiley:

And yeah, I believe you are right in regards to that not being a high enough voltage :\

I am working with a buddy on this and he said "I am hoping to design a trigger with 0-5v out - a simple button and pot and out.

I am almost wondering if he isnt simply meaning something like a Pad or Drum trigger? Push button and bass drum - and then pot controls the velocity? or something… idk lol

or like CV attenuation? like, pushes the button and it will vary the cv to whatever the pot is set to?

Now im scratching my head.

But yes! thank you for that diagram. I’ll run that one past him and see if thats actually what he is thinking to do haha

does it sound like i am over thinking all of this? :stuck_out_tongue:

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No, but maybe your buddy has under-thought it! Ask him what he actually wants to do. I’ll bet as soon as he tells you you’ll see a clearer answer, something that’s been done to death already!

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Like this thing but with attenuation.
https://www.synthrotek.com/products/modular-circuits/arcadian-rhythms/

How do? lolol

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What do you plan to connect it to? If it’s a high impedance (i.e. buffered) input, you can just use a simple voltage divider, like Bitnik suggested above. If you have a +5 V supply, you can just use a pot as a voltage divider directly, with e.g. a 1k on the way out to limit the current in case you plug it in in the wrong place:

If you only have +12 V, add a resistor before the pot to shave off 7 volts:

EDIT: you may still want to include the 1k output resistor, to protect against shorting something else to ground via this output, but that’s probably less likely than accidentally shorting the output from this module to ground.

Note that 14k isn’t a standard resistor value, but you can use e.g. a 10k and a 3.9k in series, or if a slight overshoot in the maximum position is ok a 12k.

If the input impedance is too low in relation to the potentiometer value, it will interfere with the voltage divider and you need an output buffer to get a stable voltage.

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Drums trigger - low side of the pot - up to a VCA - high side of the pot -
is what we’re both thinking.

You guys are wonderful <3

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Low side of the pot probably won’t set off a trigger unless it’s somehow “pulled up” like a microcontroller input (because it will be right about 0v.) Is the idea to have a single button that triggers different sounds based on the position of the pot?