Re: PCjr Monitor Issue
Unread postby codavec » Sun Feb 04, 2018 6:48 pm

I finally had some time this weekend to compile a list of capacitors needed for the PCjr Display. A fully completed recap will include both the analog board (power board, whatever you want to call it), and the neck board. The neck board has a protective shield in place that must be desoldered before the capacitors can be removed. The analog board also has a cover that is held in place with plastic standoff clips.You'll need to desolder the ground strap from this cover before removing it to replace the analog board capacitors. On initial disassembly, there were no obvious signs of cap leakage. However, as I began removing caps, I found at least three that were leaking from the bottom. As always, exercise caution when working within a CRT monitor. High voltages may be present, yadda, yadda, yadda. Having powered up the monitor the day before disassembly, I made sure to bleed off the flyback transformer. If any of you aren't sure what this means, an Internet search will provide you with the information you need. In my case, there was no popping sound, or crazy sparks. There may be a bleed-off resistor in place to discharge the flyback, but I wouldn't count on it. Safety first, folks!

Anyway, on to the stuff you're really here for.

The neck board has seven capacitors (in no particular order -- it was just the order in which I wrote them down):

1. C201 - 330uF 10v
2. C205 - 100uF 25v
3. C204 - 470uF 6.3v
4. C203 - 200uF 10v
5. C607 - 100uF 25v
6. C601 - 4.7uF 250v
7. C209 - 0.1uF 50v

The analog board has 25 capacitors (again, in no particular order):

1. C405 - 3.3uF 50v
2. C303 - 100uF 10v
3. C302 - 10uF 50v
4. C301 - 330uF 16v
5. C955 - 330uF 16v
6. C304 - 4.7uF 50v
7. C515 - 1uF 100v
8. C529 - 10uF 50v
9. C953 - 330uF 180v (LEAKING)
10. C530 - 10uF 160v (LEAKING)
11. C502 - 1uF 50v
12. C501 - 4.7uF 50v
13. C909 - 22uF 50v
14. C913 - 47uF 25v
15. C908 - 2.2uF 50v
16. C906 - 150uF 250v
17. C524 - 10uF 50v
18. C519 - 22uF 25v
19. C412 - 470uF 16v
20. C409 - 100uF 100v
21. C408 - 1000uF 6.3v
22. C407 - 3.3uF 350v (LEAKING)
23. C512 - 22uF 200v
24. C406 - 100uF 10v
25. C514 - 470uF 25v

Total time spent removing and replacing caps was at least an hour. I will report back with the results of this job once the monitor is reassembled.