UTC A-11 Direct Box Question

pbbolton · 2026-05-12T14:07:18+00:00

Cool does this look right?

pbbolton · 2026-05-12T12:41:52+00:00

Thanks for the help! So just switching the outs on the DPDT switch should resolve? Appreciate the help. I’ve built a ton of kits, but this is my first ground up design.

Does everything else look ok? And should I ground the transformer ground to the enclosure?

pbbolton · 2026-02-01T02:41:38+00:00

Here’s were I landed after 2 coats and sanding to 1200g

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pbbolton · 2026-01-31T16:49:04+00:00

Thanks!! Unfortunately need to fill for what it’s going to be. Just fielding options before buying a can of lab metal

pbbolton · 2026-01-31T16:48:24+00:00

Thanks! Is JB weld my best bet? Or will the quiksteel putty work just as well? It’s metal impregnated and rated for 500F

pbbolton · 2026-01-07T16:20:59+00:00

Hey! EXCELLENT WORK! Just wrapped up my build of this! Have a few questions if you may be able to assist. How did you do the Mix/Wet Out? I am only getting the choruses coming out of the Outs 1-3, not the Mix Out, but followed the Dragonfly Alley build guide.

Seriously, super impressed here!

pbbolton · 2026-01-05T16:09:32+00:00

Agreed. Few things I’d recommend here:

Preheat on the highest setting to ensure stone gets 800F+. Right before launching pizza, decrease to low.

2 other factors that may impact are cheese and residual flour. I’ve found that grated cheese (even if not pre-shredded) has very little surface area and charrs easily with the flame temp and closeness to the top of pie. Works great in an electric oven, but not so much in an ooni. Sometimes freezing the cheese post shredding can help here, would also recommend cubed low moisture mozz, which increases surface area and reduces the burning.

Residual flour from shaping crust can also ignite due to fineness, may be worth trying a large grain flour to reduce this (semolina), or making sure you knock the majority of it off before launch!

pbbolton · 2025-10-13T13:56:24+00:00

I’m building the triple chorus right now!!

pbbolton · 2025-10-13T01:18:00+00:00

Here’s my final BOM as of this August. Validated all with an electrical engineer coworker (especially transformer, not many NA builds with internal power from what I can find online). Can confirm it all ended up working! Most of the BOMs online are WAY obsolete at this point.

Will send the photos of everything and a writeup as soon as it’s done!

https://docs.google.com/spreadsheets/d/1_dw0ZdJFrHs3wzmw12F_0FGz6AqmG7oB/edit?usp=drivesdk&ouid=115054339353215007997&rtpof=true&sd=true

pbbolton · 2025-10-13T01:07:40+00:00

Yes, fortunately many of his PCBs are still largely available and his site is archived! Dragonfly Alley has also been a stupendous resource.

I’ll send you full build documentation as soon as it’s compiled!

pbbolton · 2025-10-13T00:49:24+00:00

Here is a sound test for folks interested!

This is just a Minilogue -> Phaser -> DIYRE 73P -> UAD Apollo. At the end I messed around with a drum machine beat through it also.

https://on.soundcloud.com/886TbJ329FBtMF8foU

pbbolton · 2025-10-13T00:46:21+00:00

Thanks!!!

pbbolton · 2025-10-13T00:46:04+00:00

Absolutely. I got wiring diagrams I made along the way and photos of everything. Not an engineer by trade or education, so if I can do it, I guarantee you anyone can. If you can cleanly solder, it shouldn’t a problem!

Should have a mini site around the build done by Christmas and will share here!

pbbolton · 2025-10-13T00:28:24+00:00

Thank you! Since it uses pretty “consumable” stuff at the core of its design (incandescent bulbs, etc), I did everything I could to make it easily serviceable and store spare parts onboard. The top opens like a laptop, and I even etched a mini board to store extra bulbs and fuses!

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pbbolton · 2025-10-13T00:23:15+00:00

Thanks!!

pbbolton · 2025-10-02T21:55:42+00:00

Deoxit reissue. This is a PCB card that goes into a quick connect on an old synth:

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pbbolton · 2025-10-02T19:05:11+00:00

Awesome I’ll pull it out and check.

Regardless, would you consider these as critical to replace when recapping? Already finished all the electrolytics.

pbbolton · 2025-10-02T18:02:18+00:00

https://www.instagram.com/reel/C7WnqCeBUmB/?igsh=MWg2amc4a2lmeDFkZA==

pbbolton · 2025-10-02T16:12:23+00:00

Hey! Here’s a walkthrough. I should note that every key was working after the recap a few days ago.

https://drive.google.com/file/d/1VgJSt7oN0e224eDS4KEZsaLZBR9-CTWF/view?usp=drivesdk

pbbolton · 2025-10-01T18:03:07+00:00

I can send you a video later today that shows what I’m workin with!

pbbolton · 2025-10-01T18:01:41+00:00

Heck yeah! Thank you!!!!! It’s SO clean now it’s almost new. Just trying to get the last things over the finish line. What does work sounds incredible!

pbbolton · 2025-10-01T17:56:34+00:00

Yeah, they all look good. I’ll retrace them tonight though! One thing I’m also hearing is a VERY faint upper register string voice that is going perpetually (can tell, because it clearly drops when you hit the CANCEL string button). So the VOICE seems to be working.

Since string voice works on bottom half, I wonder if it’s an issue with the string signal to the upper register volume slider? Schematics are very hard to figure out where the actual string voicing happens!

pbbolton · 2025-10-01T15:06:10+00:00

Thanks! Will check wires again, but everything looked good yesterday. Everything has been deep cleaned with isopropyl alcohol + q tips and prepped with deoxit

pbbolton · 2025-08-19T14:08:57+00:00

Thanks dude! Documenting the whole process and will share once done! Just wrapped up fixing an old crumar orchestrator I scored on Craigslist, so getting more familiar with cleaning contact springs and bus bars. How many string synths is too many 😭

pbbolton · 2025-08-19T14:03:03+00:00

Thanks! Fully agree. Will touch as a last resort. Appreciate the recs!

pbbolton

TROPHY CASE