I have received a nice set of Mullard germaniums from Small Bear, but I'm not sure if his resistor values correlate directly to the Mangler. I looked through some old threads, but couldn't find a definitive answer. Does R3 = R3, etc?
Small Bear says
R3 - 22K
R4 - 680 ohms
R5 - 11K
R6 - 110K
Madbean says
R3 - 220 ohms
R4 - 470 ohms
R5 - 47 ohms
R6 - 4.7K
The Small Bear package says
Q1
87, L = 229
Q2
103, L = 264
I tried using this thing, but can't figure it out.
http://www.diystompboxes.com/biascalc/bmbias.html
Thanks
I think I may need to take some macro shots of them before they go in. They kind of look cool.
Still confused.
On the bear face page:
"Clean-up pot R2 is optional."
On the fur face page:
"The only other thing I added was a 1 Meg resistor from input to ground to reduce "pop" noise from the stomp switch."
R1 on small bear's pedal is a 1 meg
Small Bear's resistor numbers are shown on their Bear Face schematic (see https://www.smallbearelec.com/Projects/BearFace/BearFace.htm (https://www.smallbearelec.com/Projects/BearFace/BearFace.htm)). You need to compare that with the Mangler schematic to figure out what resistor goes where. I worked through it and it turned out fine using the following pairs:
Small Bear Resistor # = Madbean Resistor #
R3=R2
R4=R4
R5=R3
R6=R1
However, I jumpered Madbean's R3 and used only the 10K trim pot to get the correct bias point.
Hope that helps.
Thank you. I'll try that out.