Optical hihat controller

[dmitri]

Most important is what voltage you get on pin 13 of the first MUXer when you press/release the pedal.

[Akkue39]

Thank you Dmitri, that was the right tip. I got 0V on Pin 13 and i've wondered why. It is so simple. I use switches as jumpers on synthex kit. But one of them is simply broken. Damn. What have i learnd anymore? Sometimes it's better to look at the enviroment. Now i can see the bar running up and down. Thank you very much.

Best regards

[russtolium]

I've breadboarded up Dmitri's version of the circuit myself and I'm having a bit of trouble getting things going. Here's a few measurements of what I'm seeing so far:

4.88 V across the TRS cable's Ring and Sleeve
1.5 V across the TRS cable's Tip and Sleeve (this strikes me as particularly odd since I thought the tip only received voltage from the ring)

Tried another cable to make sure it wasn't the problem, same thing.

I swapped out the photo-resistor for a direct connection to make note of what the max voltage definitely is. I assume that something around 3.6 V is correct based on what others have said? Basically, since the tip seems to always have a voltage of 1.5, that's as low as it will go. Swapping the direct connection in for a photo resistor and exposing it to more/less light seems to alter the voltage as expected, but never goes below 1.5.

I have the impedance switch set to low (also tried hi with no success) and my low/hi levels set to 40/200 with levelsauto and altin set to no. Hours of tweaking and testing aren't yielding anything useful so far...

[jman 31]

I've breadboarded up Dmitri's version of the circuit myself and I'm having a bit of trouble getting things going. Here's a few measurements of what I'm seeing so far:

4.88 V across the TRS cable's Ring and Sleeve
1.5 V across the TRS cable's Tip and Sleeve (this strikes me as particularly odd since I thought the tip only received voltage from the ring)

Tried another cable to make sure it wasn't the problem, same thing.

I swapped out the photo-resistor for a direct connection to make note of what the max voltage definitely is. I assume that something around 3.6 V is correct based on what others have said? Basically, since the tip seems to always have a voltage of 1.5, that's as low as it will go. Swapping the direct connection in for a photo resistor and exposing it to more/less light seems to alter the voltage as expected, but never goes below 1.5.

I have the impedance switch set to low (also tried hi with no success) and my low/hi levels set to 40/200 with levelsauto and altin set to no. Hours of tweaking and testing aren't yielding anything useful so far...

What type of photo-transistor are you using? Infrared don't work for crap.

[russtolium]

Hi jman, it turns out that I have a 850 nM phototransistor which for some reason didn't occur to me until now was infrared: PHOTOTRANSISTOR NPN 850NM

... So that is a problem that'll need a replacement, but that still doesn't explain why the tip of the plug is showing 1.5 V with nothing connected to it. It should be reading close to zero, right?

I swapped out the phototransistor entirely with a jumper to get my 3.6 V max reading, and when I remove it I once again get 1.5 V at the tip despite the circuit being severed. The only thing I can think of is that there's some hi hat setting that I'm not thinking of that might be causing it or something is contacting the tip inside the module that shouldn't be...

[CyRuS]

I have an Alesis Trigger iO and from the pedal output I get a 3.75V tension, how can I adapt dimitri's circuit to my drumkit module?

[dmitri]

I have an Alesis Trigger iO and from the pedal output I get a 3.75V tension, how can I adapt dimitri's circuit to my drumkit module?

I believe you had better ask Alesis Trigger iO related questions on Alesis specific forums. I guess you'll find more people there with Alesis's experience.

[CyRuS]

I've connected a simple photoresistance to the HH input of my alesis Trigger iO module and then I illuminated it with a led, it seems to work but I need something to vary the luminosity flux hitting the photoresistance and obtain al the in-between nots of the hi-hat, any idea about how this can be done?

[Sylv1co]

This is what I used in the past, and it works great :http://www.megadrum.info/forums/viewtopic.php?f=3&t=949&p=12279#p12279.
I think it will not work with infrared led, but I understood that you're not using one.

But most common way to do is about like this one :
http://www.vdrums.com/forum/album.php?albumid=110&attachmentid=18034

[CyRuS]

That's smart, thank you very much!