Tremulus Lune LED questions?

[rudeez]

Hi everyone.
I'm pretty green with diy pedals but I'm slowly learning, finished 2 pedals so far, the OCD and big muff clones.
Next project will be the tremulus lune but I'm having a hard time understand all this LDR, VTL5C2 stuff.
What i want is a lune like this, with a bypass led ofc (yeah, that's from the 3PDT i get that) and then the led blinking along the trem.
http://www.youtube.com/watch?v=7b4C3up1wkU&feature=related

I found several vero layouts for this but can't get my head around what i need for it.
There is this one http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38790&g2_serialNumber=4
And then this http://www.sabrotone.com/wp-content/uploads/2011/12/TremulusLune.gif
I prefer the second layout even tho it's not verified yet, takes less space.
R13 says LDR, how am i supposed to be able to know the values of it?
Also it says that its supposed to be sleeved with the LED or something.
I know that this sounds ridiculous to some but for a greenie like me i wanna learn how it works and what has to be done.
Could someone be kind and maybe explain a little about it and point me in the right direction?
I guess buying LDR's from ebay would be the easiest way for me to get them, kinda expensive else.

Clueless greenie, Jimmie 

[CurtisWCole]

Hi everyone.
I'm pretty green with diy pedals but I'm slowly learning, finished 2 pedals so far, the OCD and big muff clones.
Next project will be the tremulus lune but I'm having a hard time understand all this LDR, VTL5C2 stuff.
What i want is a lune like this, with a bypass led ofc (yeah, that's from the 3PDT i get that) and then the led blinking along the trem.
http://www.youtube.com/watch?v=7b4C3up1wkU&feature=related

I found several vero layouts for this but can't get my head around what i need for it.
There is this one http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38790&g2_serialNumber=4
And then this http://www.sabrotone.com/wp-content/uploads/2011/12/TremulusLune.gif
I prefer the second layout even tho it's not verified yet, takes less space.
R13 says LDR, how am i supposed to be able to know the values of it?
Also it says that its supposed to be sleeved with the LED or something.
I know that this sounds ridiculous to some but for a greenie like me i wanna learn how it works and what has to be done.
Could someone be kind and maybe explain a little about it and point me in the right direction?
I guess buying LDR's from ebay would be the easiest way for me to get them, kinda expensive else.

Clueless greenie, Jimmie  

The value of the the resistor is (no offense) dependent on the amount of light the LED is giving it. 2. What they're referring to is the optocoupler. Essentially, it is a LED and resistor in one. You can check out the resistances on these things on some data sheets. You would use one or the other. Check out www.smallbearelec.com for these sorts of things. They're a great source for these specific projects. I'm clearly not as smart and as experienced as all of our friends here. Hopefully they could elaborate further if my help wasn't helpful. But I'm happy to try.

Cheers,

Curtis

[smallbearelec]

I'm having a hard time understand all this LDR, VTL5C2 stuff.

A photocoupler has a light-dependent resistor (LDR) on one side and an LED on the other. You can buy one ready-made...the VTL5C2, VTL5C3, and NSL-32 will differ slightly in the percussiveness that they impart, but are all known to work in the Lune. You can also cobble one from an inexpensive photocell and a 5mm high-brightness red LED. Other people here will suggest suitable types if you want to go that route.

[PRR]

> LDR, how am i supposed to be able to know the values of it?

{As Curtis says} The _resistance_ is "low" (~~1K) in sunlight, "high" (~~1Meg) in utter dead darkness.

To use this fact, you can carry the LDR out in the sun and down to the coalbin, shine a light and block it with your hat, or use a variable lamp in a light-tight enclosure.

In old days we struggled with neon and incandescent lamps in plug-shells. Metal film-cans were nice; then they switched to plastic which leaks enough light to matter. I have used thick black cardboard.

Vactrols are this idea done right. Selected LDRs carefully spaced from an LED inside a molded epoxy shell.

LED and LDR in black heat-shrink tube is the modern DIY.

LEDs vary some, LDRs vary a LOT in sensitivity. LDR trems have to have some trim for this, but LDRs vary so much that you may not be able to trim some LDRs. I have had to buy several batches of LDRs to find a few which could be adapted to my own designs.

LDR specs are very hard to interpret correctly and even harder to measure.

I would strongly suggest you first try with a known-good-for-Lune LED/LDR set. I have LEDs and I could get "assorted" LDRs 10 for $2, but I think $4-$6 to get a for-sure Vactrol is quite inexpensive.

[rudeez]

So, using a LDR means using one of these above and solder a normal bright red led to it somehow and then put it in shrinktube to black out the sensor?
Does the sensor react to the pots from the pcb since it arent meant to react on light in this build then or what? hows it working?
I bought some of ebay yesterday after reading the value of the LDR should be about 5k - 500k, found one type that was 4k-500k and another that was like 5k-80k.
For example, using the Sabrotone layout http://www.sabrotone.com/wp-content/uploads/2011/12/TremulusLune.gif
Will i simply solder a led to D1 and this will be the one blinking and pulsing and solder the LDR like in the pic above to the R17 spot and put it in shrink tube or do i get this all wrong?

Thanks for helping me even tho I fell like an idiot right now...
We all start at some point right?

[Tacoboy]

Will i simply solder a led to D1 and this will be the one blinking and pulsing and solder the LDR like in the pic above to the R17 spot and put it in shrink tube or do i get this all wrong?

Exactly! I did the same thing with my Tap Tempo Tremolo. Works like charm!!! Don't care too much about the specs of the LDR's... 

[rudeez]

Man, that helps alot!
What LED will be the one blinking and pulsing on the top of the box then if that LED is being inside a tube?
Also, is it possible to have two leds that pulsing and blinking?

[CurtisWCole]

The led and the ldr will go in either side of the shrink tubing. So no other light will disturb the functioning of the ldr. The LFO controlling the pulsing of led is what sets the constantly changing value of the ldr. That's why the vactrols (optocouplers) work so well in this situation. No leakage. You would put each peice in the spots mentioned while they're connected to each other with the tubing.
I certainly can relate to feeling inadequate in this forum but like you said we all start somewhere. And the members here are such great sources and are always both helpful and informative.

Best of luck

Curtis

[CurtisWCole]

Sorry. I was a little late.

[rudeez]

Ok, now im confusedm i still need something called LFO? cant see anything about that in the scheme :/
Care to explain?
Thanks a ton!

[deadastronaut]

lfo is part of the circuit that maks the led go on off....don't worry its part of it..

as for 2 leds on your box..yes its possible...just run 2 in series/or parallel....instead of one...

series  ......+   -....... +  -

parallel
            ....+   -.......
          <                 >
           ....+   -.......

[egasimus]

LFO stands for 'low frequency oscillator'. It's not a component which you need - it's part of the circuit which already is in there; it's what one of the dual opamps does.

As far as I remember, the Lune had two LEDs - one which went into the LED/LDR pair, and one on top of the box; the first one does all the work (controls LDR resistance) and therefore pulsates with both the rate and the depth that are set using the potentiometers; the second one only acts as a rate indicator, and pulsates with a constant depth. Harald Sabro's layout mentions an Indicator LED switch. If you would omit that, it would be like:

* The positive end of the indicator LED goes to lug 3 of the Depth pot.
* The negative end of the indicator LED goes to the point marked Indicator LED SW 1.

You could probably wire several LEDs, too. I'd recommend connecting them in parallel.

[CurtisWCole]

Ok, now im confusedm i still need something called LFO? cant see anything about that in the scheme :/
Care to explain?
Thanks a ton!

I'm sorry. I didn't mean to confuse. It's just part of the circuit that makes the led flash.

Curtis

[rudeez]

LFO stands for 'low frequency oscillator'. It's not a component which you need - it's part of the circuit which already is in there; it's what one of the dual opamps does.

As far as I remember, the Lune had two LEDs - one which went into the LED/LDR pair, and one on top of the box; the first one does all the work (controls LDR resistance) and therefore pulsates with both the rate and the depth that are set using the potentiometers; the second one only acts as a rate indicator, and pulsates with a constant depth. Harald Sabro's layout mentions an Indicator LED switch. If you would omit that, it would be like:

* The positive end of the indicator LED goes to lug 3 of the Depth pot.
* The negative end of the indicator LED goes to the point marked Indicator LED SW 1.

You could probably wire several LEDs, too. I'd recommend connecting them in parallel.

Thanks man! i really think i get it now, just waiting for the parts to arrive, if i stumble upon problems i might as well just come back here and ask all you friendly people!
Gonna try it out and take it from there. Thanks again!