tremulus lune trouble

[tskullt]

Hi everyone,
   I'm building the Lune from Tonepad's layout.   I etched the board once (not a very good job) and got nothing from the pedal.  After some investigation I found that the input signal was connected (somewhere) to the ground.   I debugged the board checking my traces and  couldn't get it going.   So I etched a new board, much better job, and resoldered all the  componants last night.  I have the same thing as before!!!   
   The one thing I'm not entirely sure about is the LED/LDR.  I've got a Vactrol from BGmicro,  how do i ensure it is in properly?  I have the led on the LED  side, and it's marked with +/-.  Is it possible it is upside down?  How do I verify this?  I know this is a newbie question but I've never used LED/LDR's before.

   Thanks for your help.

mike

 

[tskullt]

bump!

[1978]

I had some trouble with that pedal at first--all my fault of course.
If you're getting nothing, then it seems like a wiring deal.  This is probably wrong, but even if you had the led/ldr in backwards, you would probably get some sort of sound.  Did you hook up the DPDT switch?  If so, you could try putting the board's in and out connections straight to the proper jacks.  Does the rate LED flash properly, and slow down/speed up when you turn the pots?  Also, did you get the trim pot put in right?

You checked the pinout on the Vactrol?
http://users.rcn.com/oakridge.ma.ultranet/Products/Vactrol.html
When I made it, I used the separate parts electric-taped together..

Also, I got real high on life when I discovered the magic of my DMM's continuity test.  Turns out the crappy printer I use was putting tiny lines in my printouts, and by the time it got to Kinko's and back to press'n'peel, I had little gaps in some of my PCB traces.  Going over the beginning and end of every trace fixed three pedals that night.

Stick with it because the trmulus lune is sweet -- I later changed out the trimpot for a volume pot and it's nice for a boosted solo tone.  I also did the sawtooth mod which is easy. 

best,
Kevin

[KMS]

All of 1978's advice is good.

To check the LED/LDR...... power up the LED side with separate power (don't blow it)  use a pot to adjust the power if you don't know what voltage is correct.  Try a 10K pot and be sure it is on 10K when you hook the 9V battery up. While increasing the voltage with the pot you monitor the LDR side with an ohm meter. Do not open the pot all the way, you only need to see that the ohm meter measures some change, then stop the test.  No change in ohm= burnt LED and thus you can open the pot as far as you want, because it doesn't matter anymore. If the ohm meter measures change per voltage change....then it works and stop the test.

Are we to understand that your get nothing at all when you hook it up?  No flashing LED?  No sound, not even a pop when you connect the battery? If so then you might have a problem with your traces.

[tskullt]

Hi Guys,
   Thanks for the replies.   It was the LED/LDR in upside/down.   I wonder now if the original etch was ok!   Anyhow, thanks again.
Mike

btw - it is an amazing tremolo!   I can't wait to get it in a box.

[1978]

I'm glad you got it working.  At certain settings, mine used to audibly "click" along with the rate--check out the Fuzz Central page for an easy fix for that:
http://fuzzcentral.tripod.com/tremulus.html

Kevin

[KMS]

I'm glad you got it working.  At certain settings, mine used to audibly "click" along with the rate--check out the Fuzz Central page for an easy fix for that:
http://fuzzcentral.tripod.com/tremulus.html

Mine has never done that, but I used a home-made LED/LDR in the rate doubler switch, also used a CLM600 in place of the Vactrol shown on the tonepad.com layout. I also have defeated the circuit with the stomp by taking the depth to zero.  Absolutely NO noise.

It is an awesome trem unit, that is for sure.