I should really have been posting my woes with trying to assemble my DSO Shell here. Essentially though, the soldering of the thru-hole components went well enough that any dramas were handled and everything mated into the shell. Step 4 of the instructions was checking the voltages, which also went well. Step 5 calibration was another matter though…
I dug it out of it’s box this morning and went back and checked all the voltages again, there are issues…
| Reference | Manual | Actual |
|---|---|---|
| Input | 9.3V | 9.184V |
| V+ | 8.35V | 8.371V |
| AV+ | 5V +/1 2% | 4.912V |
| V- | -7.86V | 0.238V |
| AV- | -5V +/-2% | 0.778V |
| V1 | 0V | 2.181V |
| V2 | 0V | 4.346V |
| V3 | 0V | 2.525V |
| V4 | ~1.65V | 8.333V |
As you can see V-, AV-, V1, V2, V3 and V4 are all incorrect. I found a post on the JYE Tech forum - FAQ, Tips, and Troubleshooting [Updated Oct. 11, 2017] that has a section titled 2: No negative power supply. V- and AV- have a positive value less than 1V.
The first thing they tell you to do, is to check the voltage at U5 pin8 to make sure power supply is connected to the chip. This voltage should be the same as V+. Not quite sure how to do that when it’s a SMD chip that’s sandwiched in between the two boards… 
Step two, is to visually check all pins of U5 to see whether all of them are soldered good. Check the soldering of C12 and C13 as well. The soldering of U5 looks good to me, and I’ve also checked the continuity and soldering of C12 and C13 and both seem good as well. So I decided to take a photo of the chip with a macro lens:
Not sure, but that doesn’t look too happy. Not sure if I’ve wellied it with the soldering iron, or it’s it’s burnt out internally. Might buy one and see if I can replace it, although I’m not sure how I’ll get the iron tip in between those electrolytic caps and header pins…