Mad Professor - Snow White Auto Wah  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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Ice-9
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Post by Ice-9 »

@Riesling Thanks for the eagle upload, i have just had a quick look over the schematic and have spotted 1 error. You need to make a connection from pin 6 of IC2b to C4 and R9.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

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riesling
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Post by riesling »

THX.
Got it
I'll post an update soon.

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riesling
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Post by riesling »

The update

I made some minor routing changes and replaced the 100µ/35V cap with a 100µ/25V

The archive contains one pdf with complete project information and two EAGLE files
WAW_v014.zip
(271.2 KiB) Downloaded 1256 times
By the way: NOT FOR COMMERCIAL USE

Have fun with it

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roseblood11
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Post by roseblood11 »

wow, this looks really good now! Thx!!!
Have you verified it?

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sinner
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Post by sinner »

riesling, this looks really nice, thanks matey!!!

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riesling
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Post by riesling »

Still not verified 'cause I haven't ordered a pcb.
I'm working on some other projects, which I want to place on that order.
So it will take a little time until I'm able to verify it.

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yearofrolling
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Post by yearofrolling »

So someone (like me) needs to make the from that pdf file and try it?
I could do that if it wasn't etched on the top and bottom...

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Post by ckyvick »

hey in the dimebugg layout whats q3? its not listed

edit-nevermind, q4 is q3

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audioguy
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Post by audioguy »

I just built a second SWAW nd this one has a serious volume drop. I've replaced the LM324, no change, replaced the j201 I had in for the N-Jfet, swapped it for an MPF102 same issue. Its quacking really nicely, but its cutting the volume drastically.

Any possible culprits before I start ripping it apart?

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lietuvis
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Post by lietuvis »

Finished my pedal,have not put decal yet,because have no printer at home.sounds realy good on my bass,will try to modify filter section for octave down by lowering filter caps.By the way maybe someone know what capacitors should go instead of these 22n to get octave down.then it maybe just add a switch to choose filter range not only via bias.
Attachments
P1010478.jpg
P1010477.jpg
P1010476.jpg

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chicago_mike
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Post by chicago_mike »

lietuvis wrote:Finished my pedal,have not put decal yet,because have no printer at home.sounds realy good on my bass,will try to modify filter section for octave down by lowering filter caps.By the way maybe someone know what capacitors should go instead of these 22n to get octave down.then it maybe just add a switch to choose filter range not only via bias.
Wich layout did you use? It looks real neat.
Skyline FX 2013

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roseblood11
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Post by roseblood11 »

looks like Dimebuggs layout (p.7)

clean built!

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lietuvis
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Post by lietuvis »

I am using DimebuGG pcb layout posted on page 7.Big Thanks to DimebuGG !

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chicago_mike
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Post by chicago_mike »

thanks!
:)
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ckyvick
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Post by ckyvick »

+1 dimebugg layout verified, I used 2n5089s and a 2n7000- works just like the pgs demo(bias and decay are backward, not sure if thats my error or the layout)
heres how she turned out(df painted 1590C) running into a muff with the amz mod.
http://memberfiles.freewebs.com/55/22/5 ... 002211.jpg

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Syder
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Post by Syder »

ckyvick wrote:bias and decay are backward, not sure if thats my error or the layout
You know you can fix that by changing the wires between lugs 1 and 3 of the pot, right?
Nice build, beautiful swirl ;)

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Post by ckyvick »

Syder wrote:
ckyvick wrote:bias and decay are backward, not sure if thats my error or the layout
You know you can fix that by changing the wires between lugs 1 and 3 of the pot, right?
yes, i do know that :hug:
thanks for the compliments on the build, I bought the enclosure from dragonfly a while back, his swirls are the sexiest! these are more current:
http://www.rockbox.com/FORMgallery1.htm

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Jaeger
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Post by Jaeger »

Hey guys,

could someone tell me how much current this Pedal takes? (Dunno if thats the right word, its the thing you measure in Ampere ;) )
I want to know if its worth putting a battery in the pedal or not. Doesnt seem like there is a verified layout with the DC-Jack on top and Battery, right?

Maybe someone is so nice and measures the current for me? [smilie=a_okbyenow.gif] :thumbsup

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lietuvis
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Post by lietuvis »

Jaeger wrote:Hey guys,

could someone tell me how much current this Pedal takes? (Dunno if thats the right word, its the thing you measure in Ampere ;) )
I want to know if its worth putting a battery in the pedal or not. Doesnt seem like there is a verified layout with the DC-Jack on top and Battery, right?

Maybe someone is so nice and measures the current for me? [smilie=a_okbyenow.gif] :thumbsup
This is from mad professor website about snow wah :
Supply voltage: 9VDC
Current consumption at 9VDC: 15mA
Input inpedance: 500K
Output impedance: 1K
Max input -20dBV
Complete bypass (true bypass)

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roseblood11
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Post by roseblood11 »

Is it possible to use a 18V power supply?
Headroom would be better, but would the circuit still work in the same way?

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