The Photocoupler on the 4ms Tremulus Lune. ? ?

Started by analog kid, August 23, 2005, 04:27:42 PM

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analog kid

I am a little confused about this component on the Tremulus project.
I picked up the device that Phillip (F.C. ) suggests , the Silonex NSL-32
I don't quite understand whether or not using this photocoupler if there is STILL a need to do the LED/LDR combo that most people mention doing on this build? Does this part take the Place of doing it the LED /LDR way  ? OR is it just the LDR half of that combo? meaning I still have to put it together with an LED somehow and wrap it up.
This device has 4 leads coming off it , two on either side with One side's leads , the short side, marked with a "DOT" and some red on one lead where it comes out of the package MUCH like some LED's have. SO I assume this side is the LED.  The other side has long leads and the body on that side has the marking NSL  7058.
SO when using this part , Does it function as a LED/LDR wrapped in tape??
Phillip!?   He doesn't mention the need for any more than one LED on the project prt.list, which I assume is the LED soldered to the board in the RECT. LED stage of the crkt.? That LED would also be the Functional Panel led that does the flashing , correct?  I 've been confused also If there are any other led's in this crkt that actually stay inside the box. I'm probably thinking of the LED/LDR package though.?
BECAUSE , if you look at this circuit tweaking diagram at commonsound:
 http://www.commonsound.com/tremulus/tremulustweakdiagram.pdf
You will see that there is not only an LED marked at the RECT. LED section, same place Phillip's layout shows the Main LED that mounts to the panel.  BUT ALSO  , in the LFO section , there is a pad marked LED + and a pad marked LFO Out!!! So what are these?
Is this where the SILONEX "32" goes? and if so , it has 4 leads... how do you solder it in?  Same goes for Phillip's layout:
http://fuzzcentral.tripod.com/tremulus/tremuluslayout.gif
There is an LED marked on the right side, cathode off of the Depth pot lug 2,  AND beside it  Two Pads for "CDS/LDR"!! IF this is (and I assume) the Photocoupler.... Once again, It has FOUR Leads!  So how would one solder the "32" in on this layout??
Sorry  I am sure it's very simple but I want to be prepared as I"m now beginning to populate.
thanks in advance
See the man with the stage fright, just standing up there to give it all his might..

travissk

Great pedal :D

The photocoupler takes the place of an LED/LDR combination. As you found out, one of the sides "looks" like an LED symbol. The two leads on that side correspond to LED + and -, and the two leads on the other side correspond to the light-varying resistance. Just get the polarity of the LED side right, and you're good to go. (I assume yours has an appropriate range of resistances)

I don't completely understand what you're asking in the second half of the post, since I don't have acrobat installed right now and can't check that first link. The second link (fuzzcentral) has an LED+ connected to 13... if that's what you're wondering about, I think that LED is just for visual effect so you can get a readout of the current LFO tempo.

RickL

I'll confirm. There are two LEDs, one mounted on the board that shines on the LDR (the two can be replaced by the NSL-32 which is just an LED and an LDR in one package) and the other mounted on the panel to give a visual indication of the tremolo speed.

The dot on the NSL-32 indicates the cathode (-) of the LED. For more info on the NSL-32 go here: http://www.silonex.com/datasheets/specs/103708.htm

chunks717

just did one today......LED+ goes to led anode (the long side)
LED out, or stomp is the NEG side of the led, and will blink on top of your box to show you what the lfo is doing. if you want it to stop blinking when you stop trem, then run -led to on side of stomp pole, and ground to center lug..........

analog kid

thanks for the clearing up of the LED/LDR vs photocoupler issue.
However....
QuoteThere are two LEDs, one mounted on the board that shines on the LDR (the two can be replaced by the NSL-32 which is just an LED and an LDR in one package) and the other mounted on the panel to give a visual indication of the tremolo speed.
ON the layout at Fuzzcentral there is an led +/- directly beside the CDS/LDR pads , SO I take it that this is where the LED vs. LDR sides (respectively) of the NSL go. (?? )
on the other hand and this ties into a the post made by "chunk"... At the opposite side of the board there is an LED + at pad 13... AND a pad "15" for switching of LED ON/OFF!??
so questions, this pad 15 IS NOT for the LED - ? And, is what "chunk" was saying, is that with this setup the panel LED will actually be ON when the Tremolo is OFF!! ?? If so , and I'm likely wrong, is the reason you can't wire it like a normal indicator LED because it won't cycle and "flash" with the LFO?.....Well DUH!! Obviously.   better question.
What does Phillip mean by the Pad 15 "switch for LED OFF"???
Is there a need for another external switch just do get this thing to NOT blink or be lit when the effect is in bypass??If so what type and how is it wired with this pad ?   I don't recall Phillip's LUNE having any toggle or extra stomp besides the Sawtooth toggle mod and bypass stomp. SO am I missing something on this LED ON/OFF thing??
thanks guys
See the man with the stage fright, just standing up there to give it all his might..

RickL

QuoteON the layout at Fuzzcentral there is an led +/- directly beside the CDS/LDR pads , SO I take it that this is where the LED vs. LDR sides (respectively) of the NSL go. (?? )

Yes.

Quoteon the other hand and this ties into a the post made by "chunk"... At the opposite side of the board there is an LED + at pad 13... AND a pad "15" for switching of LED ON/OFF!??

This is for the indicator LED. It is wired through the third set of terminals on a 3pdt stomp switch. It serves as both a speed indicator and as an effect on/off indicator. If you want the speed indicator on all the time wire the (-) of the LED directly to pad 15.

chunks717

sorry guy.......i thought you said you were using commonsound layout....
what i wrote applies DEF. to that one, maybe to tonepad, either way,
panel LED can be on all the time (blinking) OR switched as a status indicator, if you want it to be off when in bypass mode, you must use switch to break the LED circuit regardless of what layout you use, this led has nothing to do with the function of the effect, and will work fine with or with out it, so maybe get it working first (with led/ldr), then worry about the panel LED..........good luck

analog kid

Ok I think I have just about got a good understanding of this(this will be my first experience with a tremolo or any modulation effect.. >?? IF that even IS a modulation type, I don't think so ..anyway ! I've never done anything before that uses an LFO or a blinking/Tap LED function SO....
last questions:
QuoteThis is for the indicator LED. It is wired through the third set of terminals on a 3pdt stomp switch. It serves as both a speed indicator and as an effect on/off indicator. If you want the speed indicator on all the time wire the (-) of the LED directly to pad 15
So then basically the (pad 15 switching for Led on/off) means to run signal from this pad though the 3P of the switch and into the LED Cathode, Right? Everything just .as a 3P Led is usually wired ASIDE from the signal from that Pad 15      Am i thinking correctly??
And the pad 13 signal coming off the "tied" pins of the 4558 amp is what gives the LED the Timed blinking rather than just running from basic +9v with a resistor for vltge drop??  
which by the way ,  You WILL still need to put a 1k-5k resistor from Pad 13 right?
Hope I understand now, either way though I WILL take "chunk's" advice and just get it going w/o the panel LED FIRST!! As that is just secondary. And the least stuff that's going on during first Fire Up the BETTER!!
Less DeBugging
Thanks
See the man with the stage fright, just standing up there to give it all his might..

RickL

You've pretty much got it right except you don't need another current limiting resistor. Pad 15 connects to a 1k resistor that connects to ground. That's your current limiting resistor.

Note that the 4ms layout also has the same setup, the layout is just designed to use a dpdt switch without true bypass.