freestompboxes.org

Someone recently wanted me to build them a Hotcake based on the circuit that Soulsonic posted (a blend of a couple versions of the circuit). So I drew up a new schematic, layout, and transfer for the project. I figure I might as well share it since I went to the trouble of making it.

I've built it and the layout is good to go. Print at 600dpi. See the attached zip file for all the necessary info and artwork.

UPDATE: I have slightly altered the layout and transfer image to make it easier to etch. Please download again if you have the old version.

UPDATE 2: I have decided to add the Eagle files for a 2-sided layout. Schematic and Board file are includes, so anyone can modify the files and use them for producing their own professional PCBs for fun (or profit). The layout is verified. You will need the gauss-markov parts libraries, or you can swap out part types with what is default in Eagle. The files are located in the attached file "Flapjack_Eagle.zip".

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Attached is a project PDF for those that prefer a consolidated document instead of separate image files.

UPDATE: I have slightly altered the layout and transfer image to make it easier to etch. Please download again if you have the old version.

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Just a quick build note:

For me, the Gain control is not very useful with C50K, B50K, or A50K. Too much of the high-end gain is bunched up at one end of the sweep. So I found that B10K actually works quite well.

I updated the layout slightly, so please grab the updated files if you plan to build this.

Hi Culturejam,

Thanks for sharing,

Im currently building 2 of these. I didnt have much time to debug the first one, but couldnt get it working (as yet). As you said you made it for a friend, it would be safe to assume its verfied as working?

Thanks!
Paul.

Yes, I've built two of them. It's definitely working.

If you etched from the original layout I posted, that might be the problem. The pads were too close to the ground pour, making it really hard (or impossible) not to ground everything. So double check that, and if you did use the original version, consider doing a little carving up of the copper ground pour around the pads.

Yeah, i did use the orginal and i agree, its nearly impossible not to connect pads to ground.

OK il carve around the pads to give them a bit of space, thanks for the help!

Paul

Sometimes it´s good to be lazy: I had downloaded the first version, but then I was too lazy to etch a pcb and built the circuit on vero board...

chromesphere wrote:Yeah, i did use the orginal and i agree, its nearly impossible not to connect pads to ground.

OK il carve around the pads to give them a bit of space, thanks for the help!

Sorry about that!

No no! Dont apologise Culturejam! Your layout was a huge help. I was going to attempt the metalcan version (scorchies i think) but i'd always end up with more questions then answers and then move on to something else. Your file made it happen.

oh yeah, i got one of them working last night (yay!). Sounds great! I did have a question, not sure if you know, but I ordered LM741 and recieved the other one (ua741 i think its called). Do you know if this circuit is meant to used with the ua741? Its sounds pretty good...maybe ill try a lm741 and see how it sounds...

Paul.

chromesphere wrote:oh yeah, i got one of them working last night (yay!). Sounds great!

Glad you got it working!

chromesphere wrote:I did have a question, not sure if you know, but I ordered LM741 and recieved the other one (ua741 i think its called). Do you know if this circuit is meant to used with the ua741? Its sounds pretty good...maybe ill try a lm741 and see how it sounds...

I'm pretty sure both of the ones I built were using the UA version. I believe the only difference is who made them.

put together a 1590a layout for this.. included CJs schem (thanks!). as yet unverified, but if things go well today I'll get one done by next week..



20110731 updated - the 470pF cap was wrong. also included the expressPCB file if anyone is interested.
all artwork © www.freestompboxes.org

I have decided to add the Eagle files for a 2-sided layout. Schematic and Board file are includes, so anyone can modify the files and use them for producing their own professional PCBs for fun (or profit). The layout is verified. You will need the gauss-markov parts libraries, or you can swap out part types with what is default in Eagle.

The files are located in the original post in the attached file "Flapjack_Eagle.zip".

Here's the layout image as it is now. There is a ground plane on the bottom and a +9v plane on the top layer.

just a note to say I've updated my 1590a layout. the 470pF cap was wrong.. adjusted now... sorry bout that

that said, I've bult it and verified it.. only tried it through my mac ruby, but it sounds very cool through that... kinda between an OD and a fuzz (much closer to the OD side), and kinda harmonicy... (I think that's the right word for it )

also included the expressPCB file if anyone is interested.
all artwork © https://www.freestompboxes.org

I know there are already 2 layouts here but i thought i would share mine. I used cuturejam's eagle schematic to make the brd.


Click here for layout

jimmybjj wrote:I know there are already 2 layouts here but i thought i would share mine. I used cuturejam's eagle schematic to make the brd.


Click here for layout

Did you build the pedal using this layout?... How it works?

do you have problems with the gain pot??... you used a C50k, culturejam recomends a B10K


thanks so much!. Excuse my poor english, i'm writing from chile!

Saludos!

Thanks CJ and rocklander

lukatosh wrote:

jimmybjj wrote:I know there are already 2 layouts here but i thought i would share mine. I used cuturejam's eagle schematic to make the brd.


Did you build the pedal using this layout?... How it works?

do you have problems with the gain pot??... you used a C50k, culturejam recomends a B10K


thanks so much!. Excuse my poor english, i'm writing from chile!

Saludos!

Works great.

http://www.madbeanpedals.com/forum/inde ... pic=3566.0

jimmybjj wrote:Works great.

And it's a lot better layout than mine.

Have anyone downloaded the flapjack zip file I did but it says wrong when I upload into rar viewer
Please help thanks