Then, this 100nF you mean is a bit like the other in the power filter? (C10 in the Pedal PCB schematic posted above). Exactly. Compare this Angry Charlie guts picture (C9): IMG_1064.JPG with this Sweet Tea guts picture (Angry Charlie part of the circuit on the right), where you have an SMD cap in t...

There's a lot of discussions about the difference between the AT and the Crunch Box, and in some picture we can see in the AT pedal just a third extra 100nF cap, one after the gain pot, one in the power filter as in the Crunch Box. Everybody says that this extra 100nF cap is across the ground and i...

About the EQ pot: rev log vs linear. I can't say what original pedal mount. The EQ is a linear (B) pot like the Air pot. I am sure because after endless researches I found a picture of the top side of a AT pedal circuit board, showing the B10k pot. I'd like to see this picture, too. Anyway, with my...

The EQ is a linear (B) pot like the Air pot. I am sure because after endless researches I found a picture of the top side of a AT pedal circuit board, showing the B10k pot.

Have a nice day!
Giulio

ERRATA CORRIGE:
In the schematic the emitter of the transistor goes to ground (the layout is correct though).
The ICs are 4558, not 4458.

Giulio

Traced from original, all SMD caps removed and measured. :mrgreen: CharlesEQ.jpg Full schematic (and PCBs) available here: http://www.pedalpcb.com/product/angrycharles/ Hi, thank you very much for your work. I noticed that R18 is 10k in the pedal guts shots at the beginning of this thread, so I thi...

Hi,

sure!

https://image.ibb.co/gZAYBK/Guyatone_WR ... bypass.jpg

https://image.ibb.co/ea1Uke/Guyatone_WR ... _notes.jpg

Enjoy!

Giulio

Hi,

sure!





Enjoy!

Giulio

EDIT 2: I've just learnt that this buffer I "bootstrapped" from emitter to base so the real input impedance is raised... very clever! I must give this buffer a try!

I read on the Cornish LD-1 webpage that his buffer has a 1Mohm input impedance, but from what I see on the schematic it should be no more than 320k... are we sure the schematic is correct? EDIT: I correct myself, it's even less! It should be 240k (120k + 120k) parallel to the 200k to ground... only ...

Great news! After all this time, and keeping my build unused in a drawer, I finally realized what was wrong with it: I compared the schematic of the WR3 with the "Dr. Quack" schematic, which is different but uses the same principle, and saw that C11 in the WR3 schematic was just too small!...

The circuit works, I just don't know if it is normal to have a very loud attack of the notes when the filter opens (I can't compare to the original one, unluckily)

I just realized the links I posted to my re-drawn schematic and layout are broken so, as I can't edit my post anymore, I'm re-posting it with (hopefully) working links: Hi, I am new to this forum and first of all I would like to thank you for sharing the Guyatone WR3 schematic, which I couldn't find...

I confirm that a high gain transistor is key to make the pedal work properly. An MPS18A was the best choice for me.

PS: Regarding the "nameless" transistor in the original schematic, I realized that higher gain transistors work better, since low gain ones like the 2N3904 give quite a high threshold before the "quack" starts... I wrote 2N5088 on my schematic, but I'm still experimenting and I w...

Hi, I am new to this forum and first of all I would like to thank you for sharing the Guyatone WR3 schematic, which I couldn't find anywhere else. I re-drew the schematic omitting the switching circuit to build it as a true-bypass pedal and I made a layout to use perfboard (which is what I usually u...