I have a screen with a similar situation. I've been meaning to get to it but I've been slacking. I ended up winning an auction for another m100 that is in better shape so it hasn't been a priortiy. If this method doesn't fix it I might do some experimenting with ordering new elastomer from alibaba.
On Sat, 2020-04-11 at 19:52 -0700, me wrote: > Ok I will. > Yes they did blink out and back on. One row, when i removed the > plastic stayed off and slowly blinked back in, as if the > alastomer > as expanding back out. > Some of the alastomer feels really elastic while the areas of > failure feel hard. I will make a video of the action and share > it. > > > I know that the metal enclosure is held by twisted ends. Is that > enclosure's removal ill advised? I'm sure it is. > > > On 4/11/20 7:03 PM, B4 Me100 wrote: > > > > > > > Hmmm, the only thing to try is increasing the pressure > > slightly to force more movement in the elastomer.. Also > > make > > sure the plastic is moving the elastomer. > > > > > > > > Did the other rows blink out and back on as you move along > > the elastomer strip? > > > > > > > > > > From: M100 <m100-boun...@lists.bitchin100.com> > > on behalf of me <m...@scifidan.com> > > > > Reply-To: <m...@bitchin100.com> > > > > Date: Saturday, April > > 11, 2020 at 6:44 PM > > > > To: <m100@lists.bitchin100.com> > > > > Subject: Re: [M100] > > Missing ROM elements > > > > > > > > > > > > > > > > > > > > > Okay. I sacrificed some plastic packaging and slid > > > it > > > in there with some cleaner. no joy. I spent > > > probably > > > 25-30 minutes doing it. i'm going to let it sit > > > for a > > > while and try it again. I have a honeydo list in > > > the > > > meantime. > > > Your explanations were very straight forward and I > > > appreciate it. > > > It doing this doesn't fix my problem, do you have > > > any > > > other suggestions? I did some mild twisting of > > > the pcb > > > and didn't notice any difference. > > > Meanwhile I have a 200 incoming that I look forward > > > in > > > using. It may suit my targeted needs more so than > > > the > > > 100. I have plans for the 100 though, once i can > > > see the > > > entire screen. > > > > > > > > > On 4/11/20 8:06 AM, B4 Me100 > > > wrote: > > > > > > > > > > > > > That worked :) > > > > > > > > > > > > > > > > The contacts run top and bottom of the screen > > > > there > > > > are none on the side of the screen. If you > > > > have the > > > > TRS-80 Model 100 Reference Manual page 75 has > > > > a > > > > picture of the top of the circuit board > > > > showing the > > > > contacts (link: > > > > http://www.classiccmp.org/cini/pdf/Tandy/Model%20100%20Tech%20Reference.pdf > > > > ) - they are tiny gold fingers on the board. > > > > The > > > > elastomer has bundles of vertical conductors > > > > buried in > > > > it that take the signal from the board to the > > > > bottom > > > > of the LCD glass panel and the transparent > > > > traces that > > > > run on the screen glass panels – you can just > > > > see them > > > > in the video. There is also schematic for > > > > the screen > > > > in the reference manual showing how it is > > > > arranged > > > > and pg 34 provides some more details on the > > > > arrangement. Because the units are so old the > > > > elastomer has started to harden which means > > > > it no > > > > longer presses onto the board as well as it > > > > once did. > > > > It may also depend how the unit has been > > > > stored > > > > during its lifetime. > > > > > > > > > > > > > > > > The oxidation generally occurs at the PCB to > > > > elastomer contact and a little gentle > > > > movement can > > > > sometimes clean it out and make a good > > > > contact once > > > > again. The de-oxit just helps with the > > > > process. It > > > > may take a few attempts to clean it so take > > > > your time > > > > and make sure nothing shorts out on the > > > > bottom of the > > > > board to anything else if you choose to > > > > perform the > > > > repair powered. > > > > > > > > > > > > > > > > The card has to be thin enough to fit between > > > > the > > > > metal of the screen surround and the PCB but > > > > strong > > > > enough to apply a little force to the > > > > elastomer. It > > > > is hard to get at some locations, > > > > particularly the > > > > ends, because the metal clips are in the way. > > > > As you > > > > slide the card along you should see the > > > > rows/cols > > > > blink off and hopefully the bad rows/cols > > > > come back to > > > > full operation. The cols and rows that are > > > > out in > > > > the video are on the bottom strip. > > > > > > > > > > > > > > > > > > > > From: > > > > M100 <m100-boun...@lists.bitchin100.com> > > > > on behalf of me <m...@scifidan.com> > > > > > > > > Reply-To: > > > > <m...@bitchin100.com> > > > > > > > > Date: > > > > Saturday, April 11, 2020 at 1:07 AM > > > > > > > > To: <m...@lists.bitchin100..com> > > > > > > > > Subject: Re: > > > > [M100] Missing ROM elements > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > woops i accidently unshared it > > > > > > > > > > https://www.omgwtflol.net/nextcloud/index.php/s/7tM2KkR3Q5bCQXf > > > > > It's reshared. Stupid me. > > > > > > > > > > > > > > > > > > > > On 4/10/20 9:15 PM, > > > > > B4 Me100 wrote: > > > > > > > > > > > > > > > > > > > > > The link takes me to a login > > > > > > screen? Is > > > > > > there part of the link missing. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > From: > > > > > > M100 < > > > > > > m100-boun...@lists.bitchin100.com> > > > > > > on behalf of me < > > > > > > m...@scifidan.com> > > > > > > > > > > > > Reply-To: > > > > > > <m...@bitchin100.com> > > > > > > > > > > > > Date: > > > > > > Friday, April 10, 2020 at > > > > > > 4:38 PM > > > > > > > > > > > > To: > > > > > > <m...@lists.bitchin100..com> > > > > > > > > > > > > Subject: > > > > > > Re: [M100] Missing ROM > > > > > > elements > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://www.omgwtflol.net/nextcloud/index.php/f/108057 > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >
