Sadly, most M100s I've dealt with have had damage from leaking capacitors and that damage needs to be cleaned and repaired before installing new capacitors. The boards are also usually caked in factory flux residue and that flux is now conductive enough to cause malfunctions in the system. When I get M100s in for repair, they get all the capacitors removed, all capacitor footprints inspected for damage, and the board gets scrubbed with 100% isopropyl and possibly also citric acid if the capacitor leakage is significant. It's a nasty and time-consuming job.
Once the power supply section is repaired, I feed 6 volts from my bench power supply and the unit should draw 65mA or less. Any more and there's still leakage in the power supply section. -Josh On Sun, May 19, 2024 at 7:35 PM Jim Williams <hira...@hotmail.com> wrote: > I recapped my two M100s. > > The first one required some flux-cleaning and then worked fine. So I put > it on its shelf, and recapped the second one. > After, the second one was completely dead; no battery light, no sign of > life whatsoever. > I took it apart again and thoroughly cleaned it with alcohol because I'd > been told that excessive flux could be an issue. > I also checked all the capacitors and the battery to ensure that they were > all soldered properly. They all appear to be so. > > After reassembly, it was still just as dead. > So I returned to my first M100, intending to install a RexCPM into it. > Before doing so, I flipped it on, and the low battery light came on... and > nothing else. > I replaced the batteries with new ones... and all that happened was the > low battery light flickered as I turned it off. > I adjusted the contast knob, just in case it was something that simple, > but to no avail. > > So I put it back on its shelf to deal with another day, saddened that I > now have no functioning M100s; that I killed them. > A few hours later I took it off the shelf... still the battery light > flicker, but, I accidentally pressed several of the keys. > Whenever I press a key, I get a beep. > > Can anyone with more experience advise me on how to further investigate > what could be wrong with my machines? At this point, I'll settle for one > working. > >
