Tremulous Bear Photocoupler help

[Shandy]

Hi, all...

Great place you have here... I did a lot of searching of the forums and re-reading of the instructions, but I'm pretty lost when it comes to the photocoupler in Small Bear's Tremulous Bear vibrato.

It seems the kit is supposed to come with a part that looks like this:



It's the black doodad in the center with three sockets(?) on either side.  The kit came with nothing like it, and for the life of me I can't figure out how it works, or what the part even is so that I can run down to Rad Shack to get one.  I DO know that it should be a photocoupler, but I can't find any look-alikes in my Digi-Key catalog.

The kit did, however, come with a Mystery Part:



I searched the catalogs for it, but I still don't have a clue of what it is or where it goes.  It has two leads on each end, although the photo only shows one on the top.  Or is it the bottom?  Good Lord.

Here is the schem:



Any advice?  Specifically, what part should I buy to get this thing up and running?  Is my mystery part even related to the kit at all, or just a cruel joke on the newbie?  I've been doing a lot of reading, and I put Small Bear's "Tweak-O" pedal together with no trouble, but this part of the project is really making me feel like an idiot.

Thanks guys...

[slacker]

Welcome to the forum.

I'm pretty sure your mystery component is your photocoupler, it just looks different to the one in the photo.
If you look at the schematic the photocoupler takes the place of LED2 and LDR1, thats all a photocoupler or optocoupler is, an LED shining on an LDR. As the LED gets brighter the resistance of the LDR gets less.
So the 4 leads are the anode and cathode of the LED and the 2 leads of the LDR.
It looks like it's got a white dot by one of the leads I think that marks the cathode (negative lead) of the LED.
Hope this helps

[Shandy]

Oh man... a HUGE help.  Makes everything a lot easier, too, by the looks of it.

Thanks, Slacker!

[smallbearelec]

Please do ask me when you have a technical question; happy customers are very important to me. I am always at smallbearelec@ix.netcom.com.

Yes, that is the photocoupler. It is actually a Clairex part that I have sorted for proper resistance to work in the Trem.

Since you were confused, I will re-read the instructions and possibly make changes to clarify what comes with the kit.

The trem is a more complex and more difficult build than the Tweak-O, but very well worth the trouble. Stay in touch, and let me know how it goes.

Regards
SD

[Shandy]

Thanks, Steve... I figured you probably had enough to do, plus, who wants to work on the weekend, right? 

I finished assembly last night, but apparently have some troubleshooting to do.  I have the right voltages in the right places, but no blinking LED, or sound at all for that matter when the unit is switched on.  When it's switched off, the bypass works fine and the signal goes through.

I still have to recheck all of my connections and look for continuity issues, so I'll probably find my problem(s) soon enough.

Thanks again!