Optical hihat controller

[jimmy939]

I would like to give this a try and combine it with the concept that 'Poco Askew' (vdrum.com user) has posted at this thread:
http://vdrums.com/forum/showthread.php?t=46103&page=2

But first, I would like to clarify component specifications:

D1 = 1n4148
C1 = 100nF
J1 = TRS Jack
R1 = 150 ohm
R2 = 56,000 ohm (56k ohm).. is this correct for R2 ?

I'd be very interested to hear your plans on combining them.
As poco askew's thing looks great, but I worry how long the potentiometer will last

[racer52]

I would like to give this a try and combine it with the concept that 'Poco Askew' (vdrum.com user) has posted at this thread:
http://vdrums.com/forum/showthread.php?t=46103&page=2
.... ....

I'd be very interested to hear your plans on combining them.
As poco askew's thing looks great, but I worry how long the potentiometer will last

Hi Jimmy...
So far, it is a plan hatched in my head...

I don't like the idea of the resistor failing. The thought is that the solid state controller will be more reliable.

My idea is to use an inner and outer tube like Poco's, w/the inner sleeve spring loaded like his.

I plan to mount the circuit on the outside of the outer tube, and have the LED and the Photoreceptor mounted so the beam is running parallel to the horizon.

I will cut a slot in the outter tube for a triangular light block to slide up and down in - thus progressivly breaking the beam as the pedal is depressed - this light block will be attached to the inner sleeve and follow the foot pedal up and down.

I am a slow mover on this.... I have collected two sections of PVC pipe that fit nicely together. I have the electronic diagram provided by dmitri, and the info from Poco Askew.

I'll try to gather up the electronic parts this week. I'll post any significant progress with this project.

In the mean time, check out my links to the other stuff I built.
I made a YouTube clip that demos both the snare drum and the dual trigger remo practice pad conversion. .. just search YouTube for " racer52online " and they will come up.

[Janado]

Hi Dimitri

Can you do a foot splash with your design?

[dmitri]

Hi Dimitri

Can you do a foot splash with your design?

Don't see how ability to make a splash depends on if the HH pedal is a potentiometer based or an opto pair based.
And btw, it's not my design, it was designed by Admir from http://www.edrum.info

[Janado]

Hey Dimitri

I didn't knew that the ability to make a splash was drum module dependent...cool to know .

As for Admir, it's because of his e-drum that i know what is DIY and that i got here to the megadrum site .

thanks again dimitri

[racer52]

I would like to give this a try and combine it with the concept that 'Poco Askew' (vdrum.com user) has posted at this thread:
http://vdrums.com/forum/showthread.php?t=46103&page=2

But first, ..........

I'd be very interested to hear your plans on combining them.
As poco askew's thing looks great, but I worry how long the potentiometer will last

I have fabricated the basic mechanical moving parts...
Video clip at YouTube:
http://www.youtube.com/watch?v=sZQBkX4SIJs

I'll post some pics in the next 1/2 hour or so...
posted pics at edrumforum.com:
http://edrumforum.com/album.php?albumid=15

I'll also post at vdrums.com

[racer52]

I would like to give this a try and combine it with the concept that 'Poco Askew' (vdrum.com user) has posted at this thread:
http://vdrums.com/forum/showthread.php?t=46103&page=2

But first, ..........

I'd be very interested to hear your plans on combining them.
As poco askew's thing looks great, but I worry how long the potentiometer will last

I have fabricated the basic mechanical moving parts...
Video clip at YouTube:
http://www.youtube.com/watch?v=sZQBkX4SIJs

I'll post some pics in the next 1/2 hour or so...
posted pics at edrumforum.com:
http://edrumforum.com/album.php?albumid=15

I'll also post at vdrums.com

Having some problems sorting this out.
I built the circuit and tried testing it on the Roland TD20. Not working

the circuit itself seems to work although it is a very small signal change at the Emitter of the Photoreceptor ( 0- 0.4 volts / blocked - unblocked light source)

I'll play with resistor values and will also try to find a hotter Photo Receptor Thi sone is an IR unit from Radio Shack. The voltage at the collector indicates that the receptor is not switching on very hard. At least that is my thought - I may be wrong about this ( it has been a long time since I dabled in electronics)

Maybe this won't work on a Roland TD20 ??
Maybe it will, and I just need some help to make it work......???



UpDate *****
this will not work with the roland TD20

[racer52]

My Internal Optical controller functions properly

too bad the Roland TD20 won't work with it
Anyone know how to make it work with a TD20??

I hooked up a 6 volt battery to the circuit Ring (+), and Sleeve (-).
I connected my O-Scope to the Tip output (cathode of the diode)

Full light from the LED produced 5 volts on the output. This varied all the way down to 0 volts when the plunger fully blocked the light !! Yeah, it Works!!

Hmm.. to bad that I do not have a drum module that it works with

I'll make a video showing it in action later this week... for now pics of the circuit installed on the plunger assembly may be seen here: ..warning - it's ugly..
http://vdrums.com/forum/picture.php?alb ... tureid=740
http://vdrums.com/forum/picture.php?alb ... tureid=741
http://vdrums.com/forum/picture.php?alb ... tureid=742

[dmitri]

When connected to TD20 what is the voltage on the sleeve?

[racer52]

When connected to TD20 what is the voltage on the sleeve?

I am at work - US, Eastern Time Zone (GMT-5)
I'll check the connected voltage levels when I go home this eve.

In the mean time - I can offer this:
From what I can recall, the Roland HHCont cable measured 3.8 volts on both the Tip and Ring, and zero on the Sleeve. This was measured open circuit, at the end of the cable that would normally plug into the VH12 HiHat cont port. -I'll double check that this eveninig also.

I have tried a variety of connection arrangements to the TD20 - none seemed to work. I even tried to power the opt cont with a battery and connect only its Tip (Cathode of Diode) to the TD20...no control.

The TD20 would only come up with a -100 as the HH OffSet - in all connection attempts.

Can you offer a suggestion on how I should connect this Opt controller to a TD20?

I was wondering if the TD 20 is looking for an external resistive voltage divider, not a variable voltage signal??? I do not know - I have not found any supporting circuit designs for the TD20/VH12 setup.

As the prototype I built actually functions, I do believe that this internal setup is a design that has its application. Maybe a Megadrum is in my future

thank you for your interest in my DIY project.