Re: [M100] In over my head? Or a Challenge!!
Hello Brad, before you start doing surgery, you didn't say if you've done the usual recovery procedures. http://bitchin100.com/wiki/index.php?title=Recovering_an_Unresponsive_Laptop -- John.
[M100] In over my head? Or a Challenge!!
Hi everyone, as the subject line says, am I in over my head (for someone with old basic electronics knowledge), or is this a worthy challenge? [TL;DR] System symptoms: Won't power the screen, BASIC doesn't really work, unusual voltages on LCD connector pins. What to do? And why?? A few months ago I received a M100 that wasn't really working. Initial symptom is no display. I was looking at this as a learning experience -- to see if I could do some simple fixes and get it going again, and dust off my ancient basic electronics knowledge. I only have a multimeter, so I knew this could be a challenge. Initial testing revealed that it did power up and will 'Beep' on command (blindly entering Basic and typing Beep). LCD does work -- I connected it to my NEC PC-8201a and had a functioning display (with a tiny line of dead pixels in zone 1). So I'm ruling out a bad LCD. The mainboard looks fine. No obvious scratches or leaking battery or caps. No obviously damaged components. No staining of any kind other than the standard-issue coating of flux (which I've read can turn conductive so I'm open to cleaning all that off too). Display-related transistors and diodes (according to the troubleshooting flowchart) check out. The caps look great too -- but I haven't desoldered each of them to test them out of circuit. I've read recommendations to recap anyway, but I'm not sure it'd be worth it if the other problems aren't related to bad caps. Voltages on the LCD Connector pins seemed weird when compared with my NEC PC8201a. Image here: https://imgur.com/a/xfNIdF1 Related to caps? Something else? The LCD is getting these voltages (the cable is fine). So now I'm thinking there might be something with the logic. So I tried typing a simple basic program, blindly, but it's a short program so I'm pretty sure I got it in properly: 10 beep 20 goto 10 Nothing. No string of beeps. And after that, a simple beep won't work either. But, power cycle or reset, enter basic, type beep, it works. beep:beep:beep also works. Now I'm thinking partially bad RAM? Or RAM select logic? So, two issues (display and BASIC), or is this all a case of a bunch of invisibly bad caps and I should just bite the bullet, desolder a few and test them. Thoughts? Ideas? What am I missing? Is this thing destined for a parts computer or could it be a good challenge to heal it up? All advice appreciated :) --Brad -- -- Brad Grier
[M100] M-10 for sale
Anybody is selling this ? (Santa Monica / CA)https://www.ebay.com/itm/Original-1st-Laptop-Olivetti-M-10-TRS-80-Model-100-in-Japan-Microsoft-1983-M10/274721819231 I wonder how a European M-10 ended up there ? - It has an AZERTY-keyboard layout, only sold in France or Belgium.- It has the stickers of the Deutsche Bundespost 1982 on it (for all of Europe, afaik) Greetings from the TyRannoSaurus Jan-80 On Tuesday, 16 March 2021, 21:37:43 CET, Peter Vollan wrote: Well, the program DIALER will persistently dial a number and then automatically call Telcom when a carrier answers. It there way to make it automatically turn on capture/download?
Re: [M100] M-10 for sale
Hi, People move around and take things with them. I have a genuine US M-100 that I bought in Hawaii when I needed to program dataloggers in the field. I won't bore you all with all the other junk I've been hauling around the world. Jonathan Ursprungligt meddelande Från : jan80...@yahoo.com Datum : 2021-03-22 - 12:13 (CEST) Till : m...@bitchin100.com Ämne : [M100] M-10 for sale Anybody is selling this ? (Santa Monica / CA) https://www.ebay.com/itm/Original-1st-Laptop-Olivetti-M-10-TRS-80-Model-100-in-Japan-Microsoft-1983-M10/274721819231 I wonder how a European M-10 ended up there ? - It has an AZERTY-keyboard layout, only sold in France or Belgium. - It has the stickers of the Deutsche Bundespost 1982 on it (for all of Europe, afaik) Greetings from the TyRannoSaurus Jan-80 On Tuesday, 16 March 2021, 21:37:43 CET, Peter Vollan wrote: Well, the program DIALER will persistently dial a number and then automatically call Telcom when a carrier answers. It there way to make it automatically turn on capture/download?
Re: [M100] Need help fixing VEE on M100
"Jeffrey Birt" wrote: > On the M100s I have found most of the caps tend to leak (and cause PCB > damage). > While I am NOT a proponent of 'recapping' every piece of vintage gear out > there on > the M100 I do a full recap on every one of them. I didn't recapped this unit because the seller I purchased it from told me he did it a couple of years ago, but I think I'll just follow your advice on this (also, I'm not sure he did clean the flux). I already have the caps so I guess I know what I'll do next week-end :o) Thanks for the advice :o) Eric
