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Good point - I think my initial testing was done with power but nothing plugged into the input or output jacks. I didn't think if that would affect the 'R' going to stereo as I haven't had a build use something going back to the jack before!

For my testing yesterday, I had things plugged into the I/O jacks, maybe that is what fixed the Pin 1 issue. Today I didn't have the jacks plugged in and Pin 1 had its issue. Anyhow, I will try some more tomorrow and see if I can get some voltage to Pin 2. FWIW I am not using a battery, just trying to get it to work with my normal 9V input.

unfortunately I took an unexplained step backwards --- today went out to work on it and I was back to the first issue as before, all power flowing to R and nothing on Pin 1 of the charge pump. I changed *literally nothing* from last night when I took all the photos to troubleshoot the C35-38 power for pin 2, and at that time Pin 1 was humming along fine.

Since I was building 2 of these at once, I swapped the second assembled board in with same jacks etc. Same issue. (!!!)  And I checked the solder on D10 again.

So, at this point I am wondering if I have some dud 2N4403 units, used in the Q1 slot. I thought maybe it was my socketing of Q1 that made a difference, but I desoldered and then resoldered the 2N4403 directly and still it was sending all the power out through the middle leg to R. By the end of it, one of them only tests as a diode in my tester so I think it is fried, but the other one tests fine so it should work but doesn't.

I have no spare 2N4403 so I am going to have to order more to evaluate this further.  For now, I am off to go work on a build that I have made before. I don't have enough hair to afford pulling out more over this! 

ps - @midwayfair I am using a stereo in, mono out (if that is what you are asking for jacks), with the ring wired to R per instructions. And Pin 2 on the LT1054 is supposed to have voltage about half of Pin 1, per spec sheet pg 3 if I am reading it right (https://cdn.shopify.com/s/files/1/0022/3952/9069/files/Thunderbird-1-18-15.pdf)

Yes -  I reflowed the solder on everything, and then after you highlighted them I even did the tantalum caps again. Maybe one is bad? I would have to order another batch from mouser as I only have 2 spares...

Hi Steve - thanks for the help so far. Here is what I am using for C35-C38. The positive pole is long leg so on right side if looking at text side, and left side if looking at blank side. I think I inserted them all correctly with long leg going into the +/square pad.  I almost wish I had them backwards since that would have been easier to troubleshoot. 

Hi - thanks that fixed Pin 1. However, still no sound. The rest of the pins on LT1054 are roughly in line with specs except pin 2 has no voltage (!?!) Based on the results from fixing pin 1, I reflowed every solder joint on the board - twice - but no luck. I tried changing out the LT1054 as well but same issue on the other one. I am getting 8.42V on Pin 1+8, but just microvolts on Pin 2 which is far less than the specs where it looks like it should be about half pin 1.
All my electro capacitors and diodes look to be installed in proper polarity And the parts involved were ordered using the Mouser BOM link in the Thunderbird build doc so I think are correct? I am baffled but still wanting to hear this thing work!

Pin 1

Pin 2

Overview top

Overview reverse

side angle

Hi - I'm doing a 1776 Thunderbird build. Got power working at least on the DC connector and my LED works! However, my latest issue at present is that power is not making it all the way through the circuit, in fact it gets stopped fairly early by the 2N4403 transistor in 'Q1' slot.

The build notes say "Use a stereo jack for the input and wire the "R" pad to the ring terminal. The purpose of the 2N4403 transistor is to avoid the return current from the charge pump IC through the same ground wire that carries the return of the input signal. The charge pump ICs draw current peaks at the switching frequency which will otherwise make its way through the signal path."

However, I am not getting any power through to my charge pump IC.
I tried 2 different 2N4403 with same result, even tried swapping my socket too. In all cases I measure ~9V going in the 'E' pin, but 9V going to 'B' and nothing reading at 'C' which looks on the specs like it then goes to the LT1054. However, I read a full 9V on the 'R' terminal that goes to the ring terminal of my stereo jack. I checked my transistor to make sure I was using the right EBC order too.

I posted pictures below. Thanks!

thanks that worked!

I had to order an alligator clip but will get to this in a week or so, thx. still broken!

this is so easy I know but it's midnight on a long day filled with baseball drafts and other things. I am still new to pedals and I am confused about power.

For my other builds I was using Rullywow 3PDT breakout boards which have spare 9V slots on them and space to connect the power-in to the breakout board.

For this one I am using a 1776 PCB (Thunderbird) and a BLMS 3PDT breakout.
The 1776 board has just one 9V slot on the board, and the BLMS breakout has no visible power input and just one V+ spot on it.

MY QUESTION: How am I supposed to connect my 9V power from the DC power jack so that the pedal works and the LED is powered on the 3PDT board?

Do I pigtail two wires to the hot terminal on the DC, sending one to the 1776's '9V' and another to the 3PDT's 'V+'? I saw one wiring diagram online that seemed to indicate so (attached)

Do I even need to send power to the 3PDT breakout separately or can I ignore the V+ slot?

Thanks in advance!

tried to show a few diff angles. bent the pots up to get the photos. they have the smallbear pot covers on them, and I can't see any two solder points touching (in some angles it looks like it but others you can see they aren't)  looking at the full board the Vol pot is upper left of the four, as you can see on the reverse side where it is labeled. Also the vol pot doesn't have much solder since I wasn't sure if I would be swapping it out again but same issue even with less solder than before.

any help you can give is great, I can't spot the trouble.

tried it again, that Vol pot is the one getting hot and making the smell.

update: I removed the old pot, put in a new B10k and am still having the same issue. So wasted a pot but I guess I know it likely isn't that (unless whole batch are duds). What should I do to troubleshoot next? All the wiring looks correct and the soldering looks ok...should I reflow all the joints on my stomp switch? I have not tried that.

I am also slightly concerned that at the lowest Vol pot setting, the LED turns off.  (see video in first post) so probably indicates a problem somewhere else? I made another VaporRay exact same way and it all turned out great so I am stumped here.

no to mention that while troubleshooting it I noticed a burning smell from the pedal... 

Hi - relatively new to pedal building. Some successes so far that I will share later. But one issue today I can't solve - I bought two Rullywow Vaporray PCB (among a few others!) My first VaporRay worked great. Second one looks the same internally, but I do not have any sound. When I turn the Vol pot I get no signal for first third and then a static pop and the LED comes on. I have attached a video showing the issue, mind the volume of your ears/speakers/headphones since there is a static pop.

I checked and I am using the correct pot (B10k) and I checked the solder lugs and they look okay. Could it be a bad pot?  Thanks for your feedback.