It's too easy to get too involved. We all do what we can, as we can, but there has to be a limit. I can't blame/fault the OP for the way they approached this issue as people come here for help and advice without knowing 'how to ask' for it - maybe that should be a 'pinned' page that all new members should be required to read?
Stuff like adding links to datasheets, listing measurements they've already taken, advising of procedures already done etc - for most new posts we inevitably end up requesting more information - very basic information - that takes up valuable time. Many forum members will no doubt have other jobs and offer their time as-and-when (like me) but we can't be here all the time....
There's no expectation from me on peoples time, I'm merely reaching out, to a potential body of minds that can help me yes get to a solution of a fix but importantly too share their knowledge so I learn more that i can apply to other fixes in the future. If a small number of people each give me just me 5% of this goal, i'm much more enriched than when I started from 0% no matter how slight their input and views right or wrong. Fair points made and here are my responses.
1. This item does not power up it has a mometary switch to the front panel and an led indicator.
2. I've measured the 9v input and about 8.8v after the Schottky diode.
3. R82 was burnt so i replaced it.
4. Resoldered most connections in the power area.
5. Thermal imaged the board, nothing alarming.
6. Q19 removed from pcb and tested with component analyser, says ok.
7. Produced schematic on KICAD
8. Modelled component behaviour in EveryCIrcuit app, (if i bypass IC13 to GND and put a larger resistor at R82 that will give me Vcc won't it at least proving IC13 is bad?)
There's no circuitry to get Vcc at 6v though, surely its not a misprint on the PCB?
