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So after successfully building a mosfet boost, I decided to try my hand at sourcing most of the components on my own for the Mimosa. I ordered a PCB and enclosure from here and got the rest off of smallbear. It went pretty well up until when I actually tried the pedal. No signal passes through the pedal until it is engaged. The LED turns on when engaged, and signal passes normally, but the pedal acts a bit funky. When engaged, the "Level" knob is very quiet up until about noon, then becomes usable, and the "Blend" knob works fine up until about 3 o'clock, then volume fades out very quickly for the rest of the turn. I followed the steps to modify this for bass, as well. Same result on both power supply, and battery. I know I'm using the correct t power supply because it works fine with my BYOC mosfet boost.

Very late in the build I realized I was using an A10k pot in place of a B10k pot on accident, but I was assured by a friend that it would work fine, but wouldn't adjust like an A10k would. I can't imagine this would have any effect on signal not passing though.

The site won't allow me to upload pictures from my phone, I will update this post with them tomorrow.

Thank you in advance.

Sounds like there's more than one problem going on here. No signal in bypass mode for a true bypass pedal is almost always one of two things--a wire connection problem at the footswitch or the footswitch itself is bad. Assuming that you wired it as per the BYOC instructions, check your solder connections at lugs 4 and 9, and make sure that you have continuity between those two lugs. If they are OK, then the footswitch should be checked with a multimeter for continuity between lugs 8 and 9 when in bypassed mode.

The second problem with the blend sounds like the compressor side of the circuit isn't working. The blend control mixes the buffered clean signal with the compressed signal--if you're getting no output at the full CW setting (all compressed, no clean), it generally means that the compressed signal is not getting to the blend pot. We really need to see photos to be able to help you effectively troubleshoot this problem. Please make them large (at least 1024 width), well-lit, well-focused shots of BOTH sides of the PCB and all of the jack and switch wiring.

Incidentally, your friend is correct that using an A10K pot for the blend control won't keep the pedal from working, but it will concentrate the useful part of the sweep way over to the CW side. A linear taper B10K pot would do a much better job there.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

I'll add pictures tonight as soon as I get home from work, my phone keeps telling me they're too large to upload. I planned on replacing the pot once I made sure the pedal was in working order, as it's going to be a few days before it ships anyway. I'll make sure to get some good shots of the footswitch as well.

Stupid question, how am I supposed to take a picture of the underside of the PCB after I've already wired it to the 9v jack?

Also, I intend on replacing the bare wire coming off the footswitch, I tried to strip a bit more off and ended up taking the whole sleeve off. I was just eager to test it out.

Haven't looked over the PCB photos yet, but the shot of the footswitch and its connections shows a major error--you have switched the wire connections for lugs 7 & 8. Fix that and see where you're at--it should at least take care of the no bypass signal issue.

Updated comments after perusing the PCB photos:

• I don't see any component misplacements, but cap C12 is installed backwards. See labeled PCB photo below.
• Be sure that the IC chip is fully inserted into the socket. It may already be, but I can't tell from the pics.
• Question: Have you adjusted the trimpot as per page 10 of the instructions?
• Looks like you'd have to unsolder the DC jack to remove the PCB. If you'd used a bit more wire, you'd be able to pivot the PCB up out of the enclosure, but the wires appear too short to allow that.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Oh wow I can't believe I missed that, thank you! That solved the bypass issue, the blend issue still remains though.

See the updated comments in my previous post.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

I believe C12 is installed the correct way, no? It's oriented the same way in the "finished" picture in the instructions kit, unless I'm misinterpreting.

Also, backside of the PCB, excuse my awful soldering, the iron I'm using is way too big to be doing this.

You are indeed misinterpreting. The positive side of the C12 cap should be on the left as viewed from the component side of the PCB with the footswitch on the bottom. The PCB is marked this way, and it agrees with the schematic. Also, the finished Mimosa pictured on page 5 of the instructions is also constructed this way. On your build, the positive side is on the right--the gray band marking the negative side of the cap is clearly on the left, as the marked up photo below shows.

That said, I doubt that this is the cause of your missing compression signal, but it should be corrected in any case.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Ah okay, there's 2 C12s on your diagram, I was looking at the wrong one. Fixed that but as you said, it didn't fix the blend issue. Went through it and cleaned up a couple solder joints and put some new wires on the footswitch and 9v jack. I'm not quite sure where to start checking with a multimeter, I've got one on hand but not very good with it.

Also as far as adjusting the bias goes, I'm pretty lost. Red lead goes to the middle outlet of the transistor and black is just grounded?

Yep. That's all there is to it. However, just use your ears at first.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com