Bluesteel Project Help

[teros]

Hi yall!

I've been working on this Bluesteel project for a couple weeks now, and I've run into some problems. I made the cardinal mistake of boxing it up before testing and it didn't work - unless I pulled on the board in a very specific way. It would operate, but it was clearly grounding out, and I got some loud pops and crackles in there. It works fine in bypass.

I bit the bullet and unboxed it, and while the LED was working, still no signal. I decided to rewire my input, output, and power jacks and test again, and still nothing. I double checked to make sure I checked all my parts and orientations (just in case) and checked to see if there were any bridges or stray wires. I also double checked to make sure I had rewired the jacks correctly.

Here's the build doc to reference for this next bit: https://www.madbeanpedals.com/projects/_folders/DistBoostOD/pdf/BlueSteel.pdf

I'm pretty lost at this point, but I decide to head in with the audio probe. I'm able to trace signal to Q2 - I have signal at the source and the gate, but nothing at the drain. Q3 still has signal at it's gate and source, so the input of the pot still has signal, but q4, c3, c4, r6, and the ouput of the 250ka dual gang pot don't have signal (along with everything else down the line, but this feels like the relevant stuff. I can absolutely do more testing around there if needed!)

I decided to look in that area for any bridges or cold solders (and I reflow a couple joints) but I audio test and I'm still getting the same results. I wish I had a bit of understanding of how the signal flowed through this little amplifier stage that the problem seems to be in, but I'm just not sure where that probing leads me to.

I then measured all voltages necessary and got this:
Measured Voltages
Positive lead at jack: 8.95v
9v in at board: 8.95v
Ground in at board: .02v 

Q1: d 8.11 s 4.30 g 2.06
Q2: d: 7.43 s: 4.00 g: 3.36
Q3 d: 8.16 s: 3.62 g: 2.28
Q4 e: 8.21 b: 7.42 c: 8.11
Q5 d 7.45 s 4.42 g 2.08
Q6 d 8.12 s 4.38 g 4.51
Q7 e 8.11 b 7.45 c 4.51
Q8 e 2.88 b 2.54 c 8.13
Q9 e 3.31 b 3.57 c 8.12
Q10 e 8.08 8.79 8.94
IC1  1: 4.05 2: 4.06 3: 4.04 4: 0.03 5: 2.78 6: 4.07 7: 4.07 8: 8.11

If it's important to note here, I used the surface mount MMBFJ201 JFET from PedalPCB for all the J201s. I'm not an expert at voltages, but the outlier in the problem area seems to be the collector at Q4, which has a significantly higher voltage than what's outlined on the build sheet. I didn't have extra 2n3906s, but I swapped Q4 and Q7 to see if I could get the signal past Q4 and still got nothing.

Here's two pictures of the board, front and back! I'm very much a beginner, so some of my solders (especially on the input and output jacks) are pretty brutal, but I've double-checked to make sure there's no continuity where there shouldn't be and that there is where there should be.
https://imgur.com/a/5GR7jpW

I think that just about covers everything - thank you so, so much for your time! I may have bit off a bit more than I can chew with this one as my 6th pedal, but I'm hoping I can get it working and I'm enjoying learning a lot along the way. Let me know if there are any more pictures that could help or any more measurements I can do, and thank you so much again!!

[jimilee]

Reflow these and check for proper component values.




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[teros]

I tried, unfortunately still nothing

[teros]

Hey yall!! I wanted to add a little update here. Good news - I found a little solder bridge, and now I'm getting signal through!! Now the issue is the output. It's significantly lower than normal both when the pedal is on and off. I've tried it completely soloed and with multiple different power supplies. The weirdest part of all of this is that after testing and getting the signal through last night, I'm having the same issue with another pedal on my board that's part of the same daisy chain. I soloed the other pedal (a joyo atmosphere reverb) and used different cables and power supplies, but nothing - and it was working totally fine before.

I'd love any thoughts on this! I'm super unsure what's happening, but I'll do some looking. Thanks yall!

[jimilee]

Bad cables? Straight to amp works fine?


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[teros]

Yeah, straight to amp works fine, but I don't think it's the cables. I isolated the pedals (so only guitar --> amp --> pedal --> back to amp) and I tested other pedals in the same spot with the same power supply and everything sounded totally normal.

[jimilee]

So you're running it in the effects loop instead of the front end?


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[teros]

I ran both problem pedals (individually) through both the effects loop and the front and I'm still getting nothing - I tried to clean off both their contacts and i triple checked that the cables I'm using are functional - I'm at a bit of a loss!

[jimilee]

Yeah, the fact it's happening to both pedals is puzzling.


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[jwin615]

I rewired an entire (new) guitar once over  over a bad(high-end brand) cable.
Just because it worked yesterday doesn't mean it's good today.
It failed the day I plugged the new guitar in. I was emailing them for wiring diagrams and everything.
(It was Chapman, so I had semi-valid concerns )
Trust me.
Maybe find a good cable(guitar to amp) then put every other cable through the effects loop?
Just out to in. And jiggle them around.
Or feed a looper into the amp and do the same.
Rule out the simple things.
The greatest strength and weakness in what we do both lie in the ground plane.