Translating a Schematic into Physical Reality

[Mr. Strypes]

Hi friends! I have a Little Green Scream Machine (TS808) PCB. PedalPCB also sells the Mean Green Metal Machine (Fortin Modded Tubescreamer), which I love! But I want to try to do the Fortin mod on the Little Greem Scream Machine myself. Looking at the schematics (attached), I see the main section of the mod is connected to the Drive section. How do I physically perform this modification?
Do I jumper legs 2 and 3 of the Drive pot, then connect a 220k resistor? Then, does the other leg of the resistor connect to a 1N4148? If so, anode or cathode? Then there's another 1N4148 diode. Anode or cathode? These all look like they form some negative feedback loop. Do they need to connect back to each other as it appears on the schematic? Finally, how does the mod return to the PCB?
Any help is very appreciated!

 

[Feral Feline]

Hi friends! I have a Little Green Scream Machine (TS808) PCB. PedalPCB also sells the Mean Green Metal Machine (Fortin Modded Tubescreamer), which I love! But I want to try to do the Fortin mod on the Little Greem Scream Machine myself. Looking at the schematics (attached), I see the main section of the mod is connected to the Drive section. How do I physically perform this modification?
Do I jumper legs 2 and 3 of the Drive pot, then connect a 220k resistor? Then, does the other leg of the resistor connect to a 1N4148? If so, anode or cathode? Then there's another 1N4148 diode. Anode or cathode? These all look like they form some negative feedback loop. Do they need to connect back to each other as it appears on the schematic? Finally, how does the mod return to the PCB?
Any help is very appreciated!

Easiest way to approach this mod is to offboard wire the drive pot...


Run a wire from the PCB's DRIVE-PAD1 to the DRIVEPOT-LUG1.

Jumper 2&3 of the DRIVEPOT, run a wire to (or just solder the) resistor-and-diode-bundle from lugs2&3 to PCB DRIVE-PAD 2 (or 3).


DONE!





Edit to add:



Maybe a combo of the above — jam all three leads of the resistor and diodes into the PCB, and run a wire from the other end to the pot.

If not all three fit in one hole...since the PCB's DRIVEPADs 2&3 are connected, you could stick the resistor in one pad, and the diodes in the other or... whatever fits — just ensure the diodes are ANTI-PARALLEL.

 

[Mr. Strypes]

Easiest way to approach this mod is to offboard wire the drive pot...


Run a wire from the PCB's DRIVE-PAD1 to the DRIVEPOT-LUG1.

Jumper 2&3 of the DRIVEPOT, run a wire to (or just solder the) resistor-and-diode-bundle from lugs2&3 to PCB DRIVE-PAD 2 (or 3).


DONE!





Edit to add:
View attachment 95343


Maybe a combo of the above — jam all three leads of the resistor and diodes into the PCB, and run a wire from the other end to the pot.

If not all three fit in one hole...since the PCB's DRIVEPADs 2&3 are connected, you could stick the resistor in one pad, and the diodes in the other or... whatever fits — just ensure the diodes are ANTI-PARALLEL.

Oh, wow! Perfect information! Thank you, Feral Feline. You get ten gold stars!

 

[mckillacuddy]

Don’t forget to substitute R6, R8, C4

 

[Mr. Strypes]

Don’t forget to substitute R6, R8, C4

Thanks! I noticed. I already made the notes in my BOM for the project. I'm mostly doing this to expand my learning, but I do like the Fortin mod more than the base Tube Screamer circuit.