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Bad news, maybe it's fault of my cheap scope, but I can't see any signal on the solenoid's pins.
I can try and troubleshoot the switching board, but it would be definitely easier to replace it with something like the nope relay bypass.
I may also design a new pcb to replace the original one.
Mmmh, need to mull it over 
EDIT: of course I couldn't see anything, the +V on the DC input is short to GND 
Now, with all the smd parts good luck to me in finding where the short is... I need to identify the reverse voltage protection diode.

Thanks, that makes sense, I'll check with my scope. So it's still possible that the relay is the culprit.
Actually, it wouldn't be difficult to replace it with a 3pdt, if it weren't for the space inside the enclosure. I'll check, but it doesn't look high enough for a mechanical switch.

Update 1: I checked the switching board, the resistance across the relay's solenoid looks fine, but I can't read any voltage when pressing the foot-switch. It's a latching relay, so I expect a voltage only when the foot-switch is activated, +5V set and -5V reset. On the other hand, also applying 5V directly to the solenoid doesn't have any effect, so I'm a bit puzzled.
There is a strange IC on the switching board, I can't find any information on the internet. It reads F1102AMB 1741N, any idea?

This is going to be tricky...

I also managed with a normal iron to solder some of them, it's a bit tricky but doable. It would be better to use solder paste, but flux with normal tin will work just fine.
I've seen the J113 mentioned as substitutes, but a quick look at the datasheet suggests otherwise. I have some of them, but never tried to swap them with J201.
All in all, considered the variation of characteristics among jfets, probably you should just get a bunch of other transistors and test them. You should do it anyhow with the J201s. Once I needed 3 of them, bought 10 and they were all completely out of specs. I had to order ten more to find 5 or 6 acceptable.
That's why in my orange MkII build I used the smd version, which is a lot cheaper and has a smaller variation in specs.

I just put my hands on a broken Danelectro Pride of Texas. Honestly, I was hoping for something easier to repair. Damn it, this thing is all smd, also tracing it (  ) will be a nightmare. However, it looks like the problem is on the switching board, so hopefully it is the relay that's faulty.
More to come when I have time to work on it...
PS: according to a couple of stickers on the box (that were casually covered by some white labels...) this was already on offer on Amazon as reconditioned.

EDIT: I just realised that probably I picked the wrong forum for this thread, if anyone reckons appropriate to move it somewhere else please go ahead.

Thanks, yes, indeed it is quite light, but it's very solid, you can step on it. Well, at least I can, but I'm not exactly what you would call a big guy  And with the velcro I can move it around without worrying about stuff flying off the board.

@Playpunk: your link is broken!

Here's the pedal board I made some time ago (things that happen when I'm home alone). I used some alluminium profiles and some scrap wood I had at home. The wood has been appropriately beaten up and stained to give it this old barn look, while the screws have been polished to a mirror finish. I like this contrast
The effects are all by me except the EQ and the looper. The power supply is a Harley Benton Powerplant Junior.
The input on the side is stereo and is split in two channels in the board, all because one of my guitars has a stereo output (E pick ups + Piezo).
The piezo channel goes to the EQ while the electric channel goes through the rest of the effects. The little box in the lower left close to the looper (the Switch) is used to switch the output between the two channels and goes directly to the looper.
I'll open a thread with some build reports of the effects in the pictures for the more curious of you  , but there's a Skreddy Lunar Module, an MXR Distortion+ slightly modded, a ROG tri-vibe, a 3Verb from Musikding with an added tone control, and the 1590DD in the middle is a ROG Ginger with a modded Condor cab sim, basically an Ampeg Portaflex + cabinet in a box. I use it with a bass, but it sounds good with guitars as well.

Hi All, I've had some experience building some distortion pedal derived from famous amps, especially from runoffgroove, and after experimenting with my take on the Orange MkII (check the 2019BOTY contest for more) I'm now trying to understand a bit more about the negative feedback.
From what I get, this is used to bring part of the signal from the output transformer back to the cathode of one of the preamp valves, where the signal phase is opposite w.r.t. the anode, in order (for example) to tame the highs or increase/reduce the distortion.
Now, some of the older projects from runoffgroove (i.e. Professor Tweed, Thunderchief and Flipster) as well as the orange project I started from, follow the original amp schematic 1:1 leaving out the final tubes and the output transformer, but include the negative feedback which, instead of taking the signal from the output transformer, takes it from the output of the pedal, which, correct me if I'm wrong, is equivalent to taking it from the output of the preamp.
My question is: without the output transformer, doesn't the negative feedback just suck signal from the output without really affecting the tone as in a real amp? Maybe this is one of the reasons runoffgroove moved away from this 1:1 philosophy to get better sounding circuits in terms of fidelity to the inspiring amp.
EDIT:
this is probably the best explanation I've seen of the negative feedback:
https://youtu.be/H5fFb5_9xyA?list=PLhv-fcfLlQdrnP4wn5wWaaO8_Y8IFrPxx

Actually, when I got home I opened the enclosure to take the picture, just to remember that the power socket is soldered to the board with very short tinned wire, so I can't take the PCB out unless I de-solder that first. But I took a close up of the component side
As for your question, I've used 9mm pots for Fuzz and Level (https://www.musikding.de/Pot-9mm-100k-log-Print-vertical), two of these (https://www.musikding.de/Potentiometer-9mm-100k-log-Print_1) for Body and Bright, and a 5mm trimmer for the Bias with a 20mm axle (https://www.musikding.de/ACP-axle-20mm-black). Unfortunately, the axle is made for 10mm trimmers, so I had to modify it a little bit to fit.
I had to use a trimmer for the Bias because I couldn't find a vertical pot of the right value (2K).
Here's the picture:

Thanks everybody! This evening I can open it up and take a picture of the other side of the board. Actually, the only way to fit it in there was to use 1/4W mini resistors from Musikding, the normal metal film ones should be mounted vertical (and I have a pcb drawing for that as well). The capacitors' size is critical too, the one that's right in the centre of the board is touching the lid of the box
@Philthy: I still have two boards of the three I ordered from Oshpark, but they all have the missing trace I mentioned above. It can be easily fixed with a bridge wire, otherwise I can share the corrected .brd file in Oshpark or directly here.

Thanks! Well, yes, I just can't do it now, as soon as I can I'll record something.

After playing a bit with a breadboarded fuzz, starting from a simple VOX fuzz (from a VOX Double Sound Wah-Fuzz), then turning it into a Jimi Hendrix FF, I decided to go for something more flexible and built the Skreddy Lunar Module.
I designed the PCB to fit a 1590A with two pots for Level and Fuzz, two pots with the small plastic shaft for Body and Bright and a trim for the Bias with the possibility to put a shaft on it and bring it out of the enclosure (which I did, and recommend).
At first I was really disappointed with the sound, until I checked the schematic and found a missing trace, nothing important, only the input signal to the base of Q2  Now I'm surprised I got any sound at all 
Anyway, fixed that and voilà, sounds great without any tweaking and with a lot of different settings. I still have to try it with a Wah.
Here's a couple of pictures. The graphic was recycled from another pedal that I didn't really like and is long gone in the spare parts bin.
PS: the LED is purple 
Enjoy:

Hi Guys, I never tried KiCad, but apparently from version 5.0 it's able to import Eagle sch/brd files (not without issues):
https://forum.kicad.info/t/kicad-5-0-eagle-import/12109
I'll give it a try as soon as possible.
Cheers,
Max.

Fuzz face after a buffer will be harsh with a lot of nasty highs. If the fuzz is 'nowhere to be heard' it sounds like you need to debug something. There are some tricks to get a fuzz to play nice after a buffer (i.e., make it sound more like it does as first in the chain): add some series resistance at the input (e.g., a 100k pot so you can tweak to taste; see Fulltone 69 fuzz), or use a small transformer (see http://www.muzique.com/lab/pickups.htm). Compare the sound (and the interaction with your playing and volume knob on the guitar) between the various methods, and with the fuzz first in chain, and see what you like best.

I manage to inspect the breadboarding and one of the circuits I used had a faulty trace. Fixed that and added a pot in series to the fuzz to adjust the impedance and it works, I can mix the wet and dry signal, and get a decent fuzz sound, but it's not really usable, it would require a lot of tinkering and I've already ordered the parts to build the DSOTM  , so I'm not going to waste any more time on this, I just wanted to put an end to this topic 
Thanks for all the answers!

R31 is a current limiting resistor like R14, therefore the voltage drop across it should be very small. The voltage is raised by TC1044 and the diodes-caps net. R31 can only cause a voltage drop, not a voltage rise, so if you have 18V after it, it will be a bit higher before, but it depends on the current flowing, according to Ohm's law.
If the current is zero then you have 18V before and after. V=RxI gives you the current drop, which would be 0, and thus W=0. W calculated as I said above is the power dissipated by that resistor with a certain current.
If you know the maximum current through R31, you can calculate the maximum power dissipated by R31 and therefore its minimum power rating. If it dissipates 0.1W it needs to be rated for at least 0.1W (of course with some margin, so, let's say 0.25W).
You can probably figure this out from the datasheets of the components downstream, but it can be tricky, you'd better use some simulation if you can.