After a couple prototypes of my prototype test box
I have completed one that I am satisfied with...
3 switches L-R: Power, Bypass, Channel: front (PCB), rear (Breadboard)
Bi-color LED indicates bypass (red) or active (green)
The board inside has polarity protection, power filtering, LED CLR and all power and ground taps.
When powered on, power is supplied to both channels at all times, regardless of bypass and channel switch position. Only the signal is routed between channels by the switch on the right side.
The stripboard on top houses 3 removable pots L-R: Volume (Output level), Sag, Gain (Input level). The pots are removeable not only to allow for different values, but I could technically stick a daughterboard or other circuit (ex vol / tone control, voltage regulator, etc) in place of a pot. The gain and sag pots also have 10K trimmers to set the floor to ground.
I wanted this since I work in a small space and virtually any pedal I work on is going to have at least a volume control and/or gain. The sag control is there if/when I want it, but I do like toying with voltage so a nice to have for me. The socket on top (first pic) is for an audio probe.
I do have one anomaly which I did not plan for but I think I like.. When the circuit is active (green LED) and I roll the guitar volume all the way down, the LED shifts to red. (There have been plenty of times I have "tried" to test, and took a few minutes to realize my guitar volume is on 0 - so a nice "feature"!) I think this is because I hijacked the input ground for the bypass LED cathode on the 3PDT and its bleeding through.. Thoughts?


3 switches L-R: Power, Bypass, Channel: front (PCB), rear (Breadboard)
Bi-color LED indicates bypass (red) or active (green)
The board inside has polarity protection, power filtering, LED CLR and all power and ground taps.
When powered on, power is supplied to both channels at all times, regardless of bypass and channel switch position. Only the signal is routed between channels by the switch on the right side.

The stripboard on top houses 3 removable pots L-R: Volume (Output level), Sag, Gain (Input level). The pots are removeable not only to allow for different values, but I could technically stick a daughterboard or other circuit (ex vol / tone control, voltage regulator, etc) in place of a pot. The gain and sag pots also have 10K trimmers to set the floor to ground.

I wanted this since I work in a small space and virtually any pedal I work on is going to have at least a volume control and/or gain. The sag control is there if/when I want it, but I do like toying with voltage so a nice to have for me. The socket on top (first pic) is for an audio probe.
I do have one anomaly which I did not plan for but I think I like.. When the circuit is active (green LED) and I roll the guitar volume all the way down, the LED shifts to red. (There have been plenty of times I have "tried" to test, and took a few minutes to realize my guitar volume is on 0 - so a nice "feature"!) I think this is because I hijacked the input ground for the bypass LED cathode on the 3PDT and its bleeding through.. Thoughts?
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