On Mon, Nov 19, 2018 at 11:41 AM Alan Perry via cctech <
cctech at classiccmp.org> wrote:
I recently picked up a Rainbow 100. The PVA between the safety glass and
the CRT on VR201 that came with it has broken down and failed badly.
I have seen videos and read about removing the safety glass, cleaning out
the PVA, and reattaching and resealing the safety glass.
All that I have seen basically sticks the safety glass on at its edges and
leaves a void where the PVA had been. It seems to me that the PVA was
providing some implosion protection. Would it work to replace the PVA and
attach the safety glass to the tube with an optically clear adhesive sheet?
I have seen that this exists, but have never used it before.
Also, I have never worked on a CRT before. I am trying to find a local
person who can observe me and stop me from doing something stupid. If I
can?t find someone, what am I more likely to do wrong? How can I be sure I
discharged it before touching it?
I have a VR201 that's like this myself, and I've been too scared to try to
fix it. Instead, I've tried bodging together various hacks to try to get
the signal into a modern composite to VGA converter...
Finally, a VR201 specific question. I booted the Rainbow over the weekend
and, looking through broken-down PVA, I could see the
Rainbow has booted
and I could enter DOS commands. I could also see white retrace lines. What
is the likely cause of that on a 35-year-old CRT?