Sandspur to Fulltone '70= No go. Help!

[cris_mas]

Greetings everyone, Cris here. This is my first technical post, so please be nice lol. Well, i've been putting together some pedal projects for myself for a while, and most of them worked. So a friend noticed this and he wanted me to build a Fulltone 70 replica. I've searched a similar project on pedalpcb and chosen the Sandspur. Since it used similar/same transistors and a relatively similar circuit i thought i would be not so difficult to copy, thinking the most difficult part was the insertion of a mid control. Well, it doesn't work XD.
I took the reference schematic from GGG (1st image) and "adapted it" to the Sandspur schematic (2nd image).
In third and fourth images i shown what i've done as adaption, but since i'm not really an eletrician/electronic pro, i don't really know if i've screwed up in some place. I've measured some components and they work, tried on point to point also and didn't worked either.
What could be my mistakes?
All help is welcome. Thanks in advance!

 

[cdwillis]

Replace R4 on the Sandspur with the 1k potentiometer. Wire lug 1 and 3 to the resistor pads. Solder the 1k resistor between legs 2 and 3 on the pot. The bias trimpot may need some adjusting to get the sundial/external bias to react the same way.

Fulltone is calling it a mid control I guess, but it's more of an overall output increase, not just midrange.

 

[cris_mas]

Replace R4 on the Sandspur with the 1k potentiometer. Wire lug 1 and 3 to the resistor pads. Solder the 1k resistor between legs 2 and 3 on the pot. The bias trimpot may need some adjusting to get the sundial/external bias to react the same way.

Fulltone is calling it a mid control I guess, but it's more of an overall output increase, not just midrange.

so the rest of the circuit is pretty much the same as the sandspur? i've managed to get something out of the point to point but is noise fest, almost unusable.

 

[cdwillis]

The Sandspur has that "clean" trimmer to add resistance before hitting Q1, but otherwise it just a silicon fuzz face. I'm not sure what tweaks Fulltone did on the 70, but it's a tweaked fuzz face and can probably be build on the same pcb by adding parts to existing solder pads where needed.

If you have a breadboard you can build one these fuzz faces pretty easily and test components out. Have you measured voltages with a multimeter on your pcb?

 

[cris_mas]

Thanks for your reply @cdwillis , I’ve followed your advice of putting the “mid” control in place of the resistor and worked! After that I’ve replaced some values and put a capacitor that I don’t know why I’ve put a wire instead. Also managed to put the germanium diode in the volume wires as shown in the first schematic and the 1n914 towards pin 2 of fuzz control and c1 + side. It finally works

Pd: since my artistic skills suck bad, I’ve contacted a talented cousin to design and paint that majestic cat named Wisconsin, who passed away some months ago, he was the furry friend of the colleague who I’m building this pedal for. I hope he likes it.
Thanks for the help dear forum