This Week on the Breadboard: Windmill (WIIO) cb mod

I took a while, as usual, but here's my incarnation.
Huge sound, yes I can smell the Hiwatt glowing. Another fab Boneyard version. Thanks so much, Sir Chuck!
Rawk.

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That feedback switch is really useful. I quite like the lower gain feedback setting, a bit more refined somehow. And still raw enough.
 
With the Feedback enabled, the distortion and gain are lower (unless GAIN is dimed), but the effect of the Tone controls is reduced as well.
 
Pardon the extremely stupid question, but I can't puzzle it out from the breadboard and my mind is a void at the moment when it comes to potentiometers.

Regarding the 10K trimpot between R101 and R102, do we lift the facing component leads of R101 and 102 to connect to pins 1 and 3 of the 10K trimpot and connect pin 2 of the trimpot to pan to the positive side of C101 for VREF?

Or do we leave everything in the board, connect R102 to pin 1, pin 2 gets attached to pin 1, and then pin 3 to R101 as more of a summing operation of resistance for something to do with VCC, since that is where the biasing is happening? (I'm guessing this one).
 
What's the story with removing the diodes? Did they really have no purpose in the original circuit.

I just picked up the version of the WIIO with the Post knob, and it sounds really good. I actually have on my pedalboard a Viceroy at medium gain going into this with the volume on the Viceroy boosted a little bit, and the WIIO also set to medium gain. Together they sound epic. (I'm practicing the solos for Comfortably Numb and need the sustain.)

With the WIIO pedal by itself I found I wanted to basically dime the gain, but when I did that the tone controls would cause oscillation above about noon. With the two drive pedals together I get a lot of choices about how much gain I want and the WIIO tone controls are more useful and don't cause oscillation.

Weirdly the WIIO doesn't like to be before the Viceroy -- it gets oscillate-ey as well.

Does any of this give any useful information about the circuit you're working on here? Happy to open up the WIIO and take pictures if you think that would be useful?
 
(To be clear I strongly prefer the sound of the Viceroy by itself when I'm normally playing but for this particular solo there is improvement in articulation with the combo of the two.)
 
gtt said:
What's the story with removing the diodes? Did they really have no purpose in the original circuit.
Click to expand...
The purpose of the zener between G & S on a MOSFET is to protect the gate against ESD. The only parts of the circuit that could be exposed to ESD once the box is closed are the IN, OUT and POWER pins. Q2 and Q3 are nowhere near any of those pins. Once Q2 & Q3 are installed on the board, they are safe from ESD events. Q1 connects to the input pin via C2 and as such is vulnerable it there is a static discharge into the input jack. D1 provides the necessary protection.

gtt said:
With the WIIO pedal by itself I found I wanted to basically dime the gain, but when I did that the tone controls would cause oscillation above about noon. With the two drive pedals together I get a lot of choices about how much gain I want and the WIIO tone controls are more useful and don't cause oscillation.
Click to expand...
This is not a troubleshooting thread. Suffice it to say that my breadboard did not oscillate.
 
Not meaning to troubleshoot. I was mentioning it in case it was helpful for thinking about what they did in the revised pedal. Sorry if distracting. I'm all over the place today.
 
gtt said:
What's the story with removing the diodes? Did they really have no purpose in the original circuit.

I just picked up the version of the WIIO with the Post knob, and it sounds really good. I actually have on my pedalboard a Viceroy at medium gain going into this with the volume on the Viceroy boosted a little bit, and the WIIO also set to medium gain. Together they sound epic. (I'm practicing the solos for Comfortably Numb and need the sustain.)

With the WIIO pedal by itself I found I wanted to basically dime the gain, but when I did that the tone controls would cause oscillation above about noon. With the two drive pedals together I get a lot of choices about how much gain I want and the WIIO tone controls are more useful and don't cause oscillation.

Weirdly the WIIO doesn't like to be before the Viceroy -- it gets oscillate-ey as well.

Does any of this give any useful information about the circuit you're working on here? Happy to open up the WIIO and take pictures if you think that would be useful?
Click to expand...

It might have to do with the feedback loop that CDB attenuated in his mods, but I agree that if it's a different version, you have to see the schematic to hazard a guess.
 
Chuck D. Bones said:
The purpose of the zener between G & S on a MOSFET is to protect the gate against ESD. The only parts of the circuit that could be exposed to ESD once the box is closed are the IN, OUT and POWER pins. Q2 and Q3 are nowhere near any of those pins. Once Q2 & Q3 are installed on the board, they are safe from ESD events. Q1 connects to the input pin via C2 and as such is vulnerable it there is a static discharge into the input jack. D1 provides the necessary protection.


This is not a troubleshooting thread. Suffice it to say that my breadboard did not oscillate.
Click to expand...

I hear that--but you are talking about the redundancy of diodes in the original design? Did the rerouting of R1 to ground require D1 be removed for the circuit to function properly, then?
 
comradehoser said:
It might have to do with the feedback loop that CDB attenuated in his mods...
Click to expand...
I seriously doubt it.

comradehoser said:
Did the rerouting of R1 to ground require D1 be removed for the circuit to function properly, then?
Click to expand...
No. Installing a JET necessitates either removing or reversing D1 because when biased into the linear mode, Vgs on an N-channel MOSFET is positive and Vgs on an N-channel JFET is negative. JFETs are not nearly as sensitive to ESD as MOSFETs, so I chose to remove D1. The JFET version will work fine with D1 in place as long as we observe the correct polarity.

Nothing I did to the WIIO circuit makes it more or less prone to oscillation. I suggest that you look elsewhere for the cause.
 
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