@cybercow
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Can’t tell where all the wires are going from the photo. And what is that connected to the “D1” point on the 3PDT PCB?
A fresh photo of things after the wiring correction was made would be helpful too.
The bypass indicator LED will not have any bearing on the “sound”.
No idea what kinda “swirling” sound you’ve got, but all fuzzes are going to have some level of a raised noise floor. That’s a given. Can you post an audio or video clip of that sound?
The first thing I see worth questioning is the orientation of the BJTs. What BJTs are you using?
I’m unable to make out any of the wiring due to the spaghetti bowl you’ve got there. :O
But is the input jack tip going directly to the main board input? Double-check the tp/sleeve of the jacks too. Again, the spaghetti makes the wiring difficult to follow.
Done? Out? With what are you done? And of what are you out? How do you mean?
Have you considered using your DMM to work out what is connected to what? Barry showed you how to use it. Have you done that?
How about R17? I notice it is NOT populated and it is one of the CLR resistors.
Also, are you using a common anode LED? A common cathode LED will NOT work.
“Nuthin'”? Did you try measuring the voltage across pins #4 & #11 on the TL074? It should be very close to the power supply.
And please, keep us updated with fresh pictures as you make these changes.
Correct. That PCB has two +9V connection points adjacent to one another. Often times, it’s helpful to have more than one +9V connection point. (I often use those 2nd +9V connection points to carry the PS over to other boards in combo builds.) Remove the wire you have going to ground from that pair and move it to one of the provided pair GND points next to the OUT solder points. Barry labels all of the solder points on his PCBs. It’s always good to pay close attention, avoiding such mistakes. 😉
Hella nice job on such wildly versatile looking build. So is this basically the “brains” box for which an external expression pedal is the treadle for this mondo wah circuit? Or is this an elaborate cocked wah circuit with an expression pedal option?
It looks like the two +9V pads have one red wire and one black (brown?) wire. If the red wire is the +9V and the black (brown?) wire is grounded – there’s the problem. And there is no ground wire connected to the GND pads. Where is the ground connected?
FWIW, I like to use a multi-run trimpot for chorus, vibe and other such circuits where a single trimpot sets up action. Multi-turn trimpots are easier to dial in an effect.
Glad you sorted it. Happy building!
OK, so your PS distribution is good.
The next thing to do is connect & fire it up in a way you can access the trimpot inside, put a signal thru it with the pedal engaged. Then with the trimpot set to center, ever so delicately, slowly and in very tiny increments, turn it it to the left to see if the “vibe” starts happening. If you get all the way to left, (again in very tiny increments), and there is still no ‘vibe’, set the trimmer back to center and start, very slowly turning it to the right, (and again in very tiny increments) till you get the ‘vibe’ sound. That trimpot setting is VERY delicate and there is a very narrow sweep point at which it will trigger the ‘vibe’ action. Be patient and delicate with the trimpot setting. The first time I built one, it took me a few minutes to find the sweet spot.
Let us know what happens after that.
The Vb will vary depending the setting of TR1.
To measure the voltages on the ICs, you need to measure at their power supply pins.
IC1 PS pin = 7
IC2 PS pin = 4
IC3 PS pin = 7
Also, ensure the JFETs are securely seated in the sockets. If they wiggle, they’re likely not going to perform well. I like to gently wrinkle the ends of the legs so they are stiff going into the sockets.
A CLR is needed only on the board to which the LED is physically attached. And the CLR value is entirely up to the builder. The lower the CLR value, the brighter the LED will be. I use anywhere between 2K7 to 12K depending on the specific LED. Typically a 3K9 or 4K7 will do fine.