To put this to bed, I found a working replacement for the 102, and harvested a couple of parts from the deceased unit - the casing, 8K RAM expansion and keyboard - so basically, all is well.
I was disappointed that it failed, though it’s always had some curious issues which came and went, so my bad for not taking better care of it and troubleshooting the problems ages ago. I will see, in time, if I can repair it, though it seems improbable given my skills and resources, and the fact that even after cleaning, in places the board is so blackened and/or crusty that I can’t actually see components or traces. Andy Well, I think I murdered it. I tried some more cleaning of the corrosion, using IPA and cotton buds, and a soft(ish) bristle brush, but afterwards, after drying it off and leaving it overnight, it now shows no signs of life at all. Not even the brief battery status flash when turning it off, and nothing on the screen. I’ve tried it with batteries and the AC adapter, and nothing. The backup battery is reading 3.87v with the mem switch off and 3.71 with the switch on, but I have no idea how to troubleshoot this. Because the 102 was actually in regular use, I’m sourcing a replacement, but I would also like to repair this one, if anyone has an idea of someone I can contact who knows how and might like to work on it (obviously for a fee!) Appreciate the help so far - I do wish I had more skills in this! Andy > I tried some more cleaning of the corrosion, using IPA and cotton buds, and a soft(ish) bristle brush, but afterwards, after drying it off and leaving it overnight, it now shows no signs of life at all. Not even the brief battery status flash when turning it off, and nothing on the screen. I’ve tried it with batteries and the AC adapter, and nothing. The backup battery is reading 3.87v with the mem switch off and 3.71 with the switch on, but I have no idea how to troubleshoot this. Because the 102 was actually in regular use, I’m sourcing a replacement, but I would also like to repair this one, if anyone has an idea of someone I can contact who knows how and might like to work on it (obviously for a fee!) Appreciate the help so far - I do wish I had more skills in this! Andy > I’ve tried it with batteries and the AC adapter, and nothing. The backup battery is reading 3.87v with the mem switch off and 3.71 with the switch on, but I have no idea how to troubleshoot this. Because the 102 was actually in regular use, I’m sourcing a replacement, but I would also like to repair this one, if anyone has an idea of someone I can contact who knows how and might like to work on it (obviously for a fee!) Appreciate the help so far - I do wish I had more skills in this! Andy > Because the 102 was actually in regular use, I’m sourcing a replacement, but I would also like to repair this one, if anyone has an idea of someone I can contact who knows how and might like to work on it (obviously for a fee!) Appreciate the help so far - I do wish I had more skills in this! Andy > Appreciate the help so far - I do wish I had more skills in this! Andy > > f the corrosion, using IPA and cotton buds, and a soft(ish) bristle brush, but afterwards, after drying it off and leaving it overnight, it now shows no signs of life at all. Not even the brief battery status flash when turning it off, and nothing on the screen. es and the AC adapter, and nothing. The backup battery is reading 3.87v with the mem switch off and 3.71 with the switch on, but I have no idea how to troubleshoot this. ally in regular use, I’m sourcing a replacement, but I would also like to repair this one, if anyone has an idea of someone I can contact who knows how and might like to work on it (obviously for a fee!) far - I do wish I had more skills in this! Andy Message: 1 > Date: Tue, 1 Oct 2024 10:17:16 -0400 > From: Andy <copypenguin at zoho.com > <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> > To: m100 at lists.bitchin100.com > <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> > Subject: Re: [M100] 102 with power-up issues > Message-ID: <86770A66-BB1E-421E-9E43-C111125A1DB1 at zoho.com > <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> > Content-Type: text/plain; charset=utf-8 > > The battery came from a well known supplier (and active member of this list), > and I think it?s good, but what clearly isn?t is the 102. I checked voltages > again last night, and got 3.7 with memory switch off, and 3.4 dropping to 3.3 > with it on. That drop in voltage now seems more consistent with the > difference between no load/load on the battery, but with prior issues this > 102 has had, there may well be hardware problems which just haven?t > manifested consistently. The fact it has corrosion on the power section of > the main board obviously means there is a problem, so I can?t really expect > it to behave entirely properly. > > This is why I was looking for a ?spare? machine, since the 102 has been in > regular use, and I?ve been depending on it even when I shouldn?t have. > > It?s been charging for a couple of days now, (mem switch on) but it still has > the same blank (all pixels on) screen at attempted starts - even when I have > had the mem switch off to create a cold start. Oddly though, yesterday it > started on the power adapter, and ran for a couple of hours quite normally, > even when I disconnected the AC adapter and ran it on batteries. So much so > that I was able to restore RAM from the Rex# in it (genius invention, Mr. > Adolph) and then use it to complete a piece of work and save to a Backpack > drive (best peripheral ever). > > Then I turned it off, and tried restarting it after 5 minutes, and it was > back to the blank screen. Since then it hasn?t booted at all. > > Andy > >> Date: Sun, 29 Sep 2024 13:51:55 -0700 >> From: "John R. Hogerhuis" <jhoger at pobox.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> >> To: m100 at bitchin100.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> >> Cc: m100 at lists.bitchin100.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> >> Subject: Re: [M100] 102 with power-up issues >> Message-ID: >> <CACutKUj_ndon9rOQuE4d=J8U15GH6MvrHLA6u6LoeOg-e=vRUw at mail.gmail.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> >> Content-Type: text/plain; charset="utf-8" >> >> The backup battery does take a fair amount of time sitting on the supply >> before it's charged up. And you should consistently be doing a cold start >> not just reset while getting the backup system going (so ram is in a clean >> state to begin with) >> >> You may well be having other issues but I recommend being consistent to >> rule out the usual issue which is backup battery fully charged and a proper >> cold start. >> >> >> >> Message: 4 >> Date: Sun, 29 Sep 2024 18:11:07 -0400 >> From: Josh Malone <josh.malone at gmail.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> >> To: m100 at bitchin100.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> >> Cc: m100 at lists.bitchin100.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> >> Subject: Re: [M100] 102 with power-up issues >> Message-ID: >> <CAB==woM+Vom1MuPgVL9_2aEaw-YJb6_gGJ3x0o5_sCtCvzJhEA at mail.gmail.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> >> Content-Type: text/plain; charset="utf-8" >> >> If memory serves, the memory battery voltage should not sag like that. >> Something is drawing too much current or your replacement battery is not >> healthy. Where did you source the new battery and what type is it? >> >> On Sun, Sep 29, 2024, 16:52 John R. Hogerhuis <jhoger at pobox.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> wrote: >> >>> The backup battery does take a fair amount of time sitting on the supply >>> before it's charged up. And you should consistently be doing a cold start >>> not just reset while getting the backup system going (so ram is in a clean >>> state to begin with) >>> >>> You may well be having other issues but I recommend being consistent to >>> rule out the usual issue which is backup battery fully charged and a proper >>> cold start. >>> >> >> Message: 5 >> Date: Sun, 29 Sep 2024 18:11:07 -0400 >> From: Josh Malone <josh.malone at gmail.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> >> To: m100 at bitchin100.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> >> Cc: m100 at lists.bitchin100.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> >> Subject: Re: [M100] 102 with power-up issues >> Message-ID: >> <CAB==woM+Vom1MuPgVL9_2aEaw-YJb6_gGJ3x0o5_sCtCvzJhEA at mail.gmail.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> >> Content-Type: text/plain; charset="utf-8" >> >> If memory serves, the memory battery voltage should not sag like that. >> Something is drawing too much current or your replacement battery is not >> healthy. Where did you source the new battery and what type is it? >> >> On Sun, Sep 29, 2024, 16:52 John R. Hogerhuis <jhoger at pobox.com >> <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>> wrote: >> >>> The backup battery does take a fair amount of time sitting on the supply >>> before it's charged up. And you should consistently be doing a cold start >>> not just reset while getting the backup system going (so ram is in a clean >>> state to begin with) >>> >>> You may well be having other issues but I recommend being consistent to >>> rule out the usual issue which is backup battery fully charged and a proper >>> cold start. >>> > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > M100 mailing list > M100 at lists.bitchin100.com > <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com> > http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com > > > ------------------------------ > > End of M100 Digest, Vol 166, Issue 1 > ************************************ Previous message (by thread): [M100] 102 with power-up issues <http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/2024-October/090069.html> Next message (by thread): [M100] CP/M On a TRS-80 Model 100 - REXCPM (YouTube video) <http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/2024-October/090071.html> Messages sorted by: [ date ] <http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/2024-October/date.html#90070> [ thread ] <http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/2024-October/thread.html#90070> [ subject ] <http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/2024-October/subject.html#90070> [ author ] <http://lists.bitchin100.com/private.cgi/m100-bitchin100.com/2024-October/author.html#90070> More information about the M100 mailing list <http://lists.bitchin100.com/listinfo.cgi/m100-bitchin100.com>
