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I've become interested in making an optical hihat controller after reading the thread started by Elrules here on the forum. (Administrators:If this thread doesn't belong here, feel free to move it to a better place)
One might think "Why start a build log about this very simple construction???". Well to me it isn't easy. My DIY variable hihat with a linear potentiometer that I'm using right now was very easy to build for me since it contained very few electronic components, but the optical hihat controller is a different animal for me. I think it has potential to be better than my current build and the components are so cheap that it's worth a try even if I fail. The support and spirit on this forum are so good that I think I have a good chance in succeeding Hopefully this build log and my MegaDrum build log will be completed at the same time so I can start experimenting with these babes at the same time.

I plan to use the schematic and components that dmitri used in his build:
D1 = 1n4148
C1 = 100nF
J1 = TRS Jack
R1 = 150 ohm
R2 = 5600 ohm


Right now I'm searching for the components and I think I've found some that might work. I'm not sure though. Here's what I'm planning to order:

Phototransistor:
http://www.electrokit.se/opto-fototrans ... a_40303208
LED:
http://www.electrokit.se/opto-led-rod-l ... s_40300002
I hope it's bright enough. I guess "mcd" measures how bright the LED is or am I wrong? This one has 2500 mcd. I've seen other ones with up to 10000 mcd but they have a diameter of 10mm and might be a bit too large size-wise.
D1:
http://www.electrokit.se/dioder-kisel-1 ... a_40310010
C1:
http://www.electrokit.se/kondensatorer- ... l_41003074
R1:
http://www.electrokit.se/motstand-0-25w ... w_40810215
R2:
http://www.electrokit.se/motstand-0-25w ... w_40810356

I haven't decided if I'll put the controller in the pedal or between the hihat cymbals...or somewhere else. My first step is to order the correct components. Step 2 will be to understand how to put the components in a working manner.

I can't read the specs on the phototransistor or the LED, but everything else looks fine.

jman 31 wrote:I can't read the specs on the phototransistor or the LED, but everything else looks fine.

I can't find more info than that it's a ultra-intensive red LED 2.15V 20mA, 5 mm 2500 mcd clear lens. (In the picture it's yellow, but the text says that it's red so I guess they just put the wrong color in the picture)

Should be OK. And the transistor will probably fine as long as it's not an infrared type.

jman 31 wrote:Should be OK. And the transistor will probably fine as long as it's not an infrared type.

There's not much info on the phototransistor. There's no text saying that it's infrared so I hope it's not...there's actually pretty much no info at all

Did they post a datasheet link for it?

jman 31 wrote:Did they post a datasheet link for it?

Unfortunately not.

I found the datasheet for the phototransistor:
http://www.electrokit.se/download/R3208.pdf

I don't see any reason why that won't work. I have some PCB's for this if you are interested PM me and I will let you know a cost. It's not much I just like to recoup a little for my time and effort.

I've now received almost all components needed to build the optical hihat controller. I also bought Jman's nice PCB for this build and as soon as I receive it (in a week hopefully) I'll start my construction and tests.