Projectile Overdrive

[Robert]

Projectile Overdrive

 

[deft]

Just finished building this - I think it's working fine but I'm not particularly blown away by it so just want to double check my biasing. 3x J201s I've set to half supply voltage, the final J201s has no trimmer so I'm also curious what that should be reading.

 

[Robert]

Voltage measurements from the original:

Q1
D - 8.43V
S - 0.264V
G - 0V

Q2
D - 8.37V
S - 0.182V
G - 0V

Q3
D - 16.54V
S - 8.23V
G - 8.37V

Q4
D - 8.4V
S - 0.292V
G - 0V




Transistor specs (as measured by DCA75):

Q1
Vgs(off)=-0.55V at Id=4.7µA
Vgs(on)=0.39V at Id=1.05mA
gfs=1.8mA/V at Id=0.6mA to 1.1mA
Idss=0.40mA at Vds=3.01V
Rds(on)=589.5Ω at Id=1.1mA and Vgs=0.0V

Q2
Vgs(off)=-0.55V at Id=5.1µA
Vgs(on)=0.39V at Id=1.01mA
gfs=1.7mA/V at Id=0.6mA to 1.0mA
Idss=0.38mA at Vds=3.01V
Rds(on)=611.3Ω at Id=1.0mA and Vgs=0.0V

Q3
Vgs(off)=-0.65V at Id=4.8µA
Vgs(on)=0.37V at Id=1.16mA
gfs=1.8mA/V at Id=0.7mA to 1.2mA
Idss=0.52mA at Vds=3.01V
Rds(on)=581.5Ω at Id=1.2mA and Vgs=0.0V

Q4
Vgs(off)=-0.65V at Id=5.2µA
Vgs(on)=0.38V at Id=1.23mA
gfs=1.9mA/V at Id=0.7mA to 1.2mA
Idss=0.54mA at Vds=3.00V
Rds(on)=563.4Ω at Id=1.2mA and Vgs=0.0V

 

[Harry Klippton]

Is the drill template the same as the normal 4-knobbers?

 

[Robert]

Yep, it's the standard 4-knob.

 

[Harry Klippton]

Thanks Bob

 

[myusernamerulez]

I would be very grateful if the build documentation would be made available as well, then I could build this kit as well. Cause based on the parts list only I can't make out all the parts myself, since I'm not that experienced (yet).
For example I'm not sure which of the C100/C101/C102 are from the parts list? Also I'm unsure about the pots etc

 

[Robert]

I would be very grateful if the build documentation would be made available as well, then I could build this kit as well.

https://docs.pedalpcb.com/project/Projectile-PedalPCB.pdf

 

[dsull]

GREAT pedal! Actually compares very well against my Filmo 385 conversion. Fells like a pedal not a Tube rectified Tube amp BUT does gets the sound & really versatile AMP in a Box! Great range of "broken tone" with the trimpots. I like D's set to 8v (pedal runs @ 16).
(Waiting on the protection diode didn't have any, but socket on there is a great idea ROCK ON Pedal PCB!!!