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Hello all, I am new to pedal building and unfortunately this pedal is not working. I’m hoping someone can cast an experienced eye over this and perhaps identify my problem. Thanks in advance.
We need additional photos that show all of the off-board wiring connections as well as a description of what is wrong.
For example: Does the circuit work in bypass? etc.
Thank you to anyone who may be able to help. There is bypass signal. The LED is working, but no effect…
Yes, in my ignorance I have lined the inside of the enclosure with tape. Could that cause a problem?
I see a problem I did not notice immediately.
It looks like the LEDs are in the wrong orientation.
The silkscreen shows a white bit over the round pad to indicate the Flat side. Also, the square pad would typically indicate that is + or Anode in this case. If I am seeing things correctly it looks like D5 (top LED) is Flat on the right side and D4 (just below) is round on the right side. It should be the opposite according to the board silkscreen and square pads.
Since a diode permits current to flow in a single direction and blocks it in the other direction using it in the wrong orientation could explain why there is no sound.
A helpful thing to remember is the
Fat Flat Cat
If that doesn’t help we will need voltages for your IC reported.
Barry – I’m pretty sure the orientation of the LEDs is not a signal killing issue. Whether they are backwards or both oriented identically, the signal should still pass – albeit somewhat horrible if both are oriented the say way. They form one of the clipping options and even if they are oriented wrong, at worst, they would be performing in an asymmetrical manner. As they are, they should really be fine. I suspect something else is afoot.
Stewart – if the bypass LED is working, that suggests the pedal is getting power. A good clear shot of the solder-side of the PCB would be good too. We would also like to know what voltages you have at the pins of the 4558 opamp. Also, the color of your pics seems a bit lack-luster and I’m not able to make out the values of the resistors. Good idea to dbl-check all the resistor values because it is so easy to insert a 100K where a 1K (or vise versa) goes. Also, with a 9V supply applied, ensure there is about +4.5V DC at the junction of R17, R18 & C11
Thank you both. I will look into everything mentioned and let you know how it goes. I’m new at this but determined it will not beat me! I have ordered another kit in case I can’t solve the problems with this one. I will win!
All the components that I can see look to be the correct value and orientation
Do your pots have plastic covers on the back of them
To remove the LEDs I suggest a good soldapult brand tool (solder sucker) in tandem with your iron.
You can also use desoldering braid.
If you don’t have either of those the pads are close so you can lay your iron tip sideways covering both pads while pulling the LED from the other side. Be careful you do not overheat the pads or your fingers.
Once you put them in correctly you can re-flow all of your solder joints as well as part of a basic troubleshooting routine. Just touch the tip to each joint to reflow the solder and have some extra solder handy in case you need just a small bit extra on a few joints.
Thank you much to everyone who helped me. It is working!
Barry, you were right the LEDs were orientated incorrectly. They are so small and my eyes missed it. Lesson learned!
Thanks again everyone.
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