Thanks!
I probably wasn't as clear as I should have been - I got these since the actual process of refurbishing something is what I enjoy and these looked like they would be fun; when they are done, though, I don't care about keeping them so I will just sell them. So, I'm not asking so much *how* to do something (other than the case yellowing removal) but rather *what* should be done from the perspective of someone who likes this type of meter. To me, they offer restoration/modification possibilities that I'm not used to having - just not sure whether they are *good* possibilities or not...
Re the display: There are several that the original displays are bad, so they will have to be replaced with *something* to be used. For the rest, it is optional - keep OEM or do something non-standard? I've found the various mods people have done and thought that some of them looked very nice - but they vary considerably from 7 segment LEDs with the original bezel to graphic OLEDs taking up the whole opening. To me, the large OLED solutions look very nice but just don't fit the style of the meter. I think that the meters have a simple elegant, retro look and a high-tech display would clash - but that's just me and why I was asking for other opinions. No matter what style of replacement though, I would not just hack something on top of the existing board. In the end, it would be a lot simpler and probably no more expensive to just design and have made a complete replacement for the display board. That way it could be easily done with no physical modifications to the meter - the old board and display (if working) could be swapped back in with no changes if desired.
Re the case: Two issues - first, how to deal with the yellowing of the case. I really would like to bring it back to it's original appearance if at all possible. The only way I am aware of is to bleach with peroxide and UV light; to do this, though, the label on the bottom of the case would have to be removed and preserved to put back on when done - which is the second issue. If repainted, the labels would not be an issue. A couple of the meters cases are broken past repair, so I can experiment on them - but I really don't want to reinvent the wheel if I don't have to. And, of course, yellowing is pretty typical of this generation of plastics so there is a lot to be said for leaving it as-is and keeping it "vintage."
Batteries? Personally, I would not want the NiCd batteries and all the issues they bring - to me, these fall into the "bench meter" category and as such the batteries aren't needed. Put together with the fact that the units with the battery option won't work without a *charged* battery installed settles the issue for me. What are your thoughts?
Again, I just do this for fun and the challenge, and don't care about keeping them when done. So, for those who *would* own a meter like this, what would of the ideas would you like? Dislike?
Thanks,
Hal