On 2012 Feb 19, at 7:05 PM, Chris M wrote: I have two (what I understand to be) Sony GDM monitors (19 inch IIRC) - one SUN-branded and one Apple-branded. They both have problems: on one the blue is gone (probably a video driver and not too difficult to repair), the other has an intermittent in the convergence circuitry - for some minutes it will be fine, then the convergence will shift for some minutes, shift back, and so on. They're boat anchors and surplus to me, and so are on the scrap/ recycle list unless somebody wants to take them away.

________________________________ From: Angel M Alganza <ama at ugr.es> I'm afraid my electronic skills (which are close to zero) won't allow me to do that. C: It doesn't require any electronics skills at all, but simply stringing wires between pins. ?How did you hope to fix a monitor if that were the case anyway??? All I can suggest is perhaps examining contacts and whatnot, perhaps some sort of cleaning.

On Wed, Feb 22, 2012 at 02:30:04AM -0500, Mouse wrote: I'd love to get good at it, but the point is that currently I'm not. I envy guys like you or I might do that at some point, but what I'd need now is to find out is if it's worth to keep those two great monitors and try to fix them or if I should just lose any hope and throw them away. :) That's the reason why I was (am) asking is if anybody might know what might have happened to them and how to check it out and, if possible, to fix them. I'm hopping whatever it might be doesn't force me to go as "low tech" as Chris suggested, because unfortunately I can't do it at this moment. I hope I don't come across as rude or ungrateful. I really appreciate all the information and efforts to help me out saving those lovely monitors. I'm just saying I don't have any electronic skills, but I can get some help with them once I find out what the problem is. Thank you. Angel -- Angel Martin Alganza Departamento de Genetica, Universidad de Granada Full contact data at http://www.ugr.es/~ama/ PGP Public key at http://www.ugr.es/~ama/ama-pgp-key ------------------------------------------------------ () ASCII Ribbon Campaign - http://www.asciiribbon.org/ /\ Against all HTML e-mail and proprietary attachments Please avoid sending me Word or PowerPoint attachments http://linux.sgms-centre.com/advocacy/no-ms-office.php

On Wed, Feb 22, 2012 at 04:48:30AM -0500, Mouse wrote: Well, not very good, I'm afraid, since I have an unsteady hand. I guess that's not an excuse, and as you said it's a matter of practise. But to be honest, I haven't been interested in electronics before and I have been lazy to try, since I know someone who I usually ask to do the soldering for me (I do other kind things for him in exchange). Oh, thank you. Indeed English isn't my native language, and unfortunately I didn't studied it at School or High School, but I learnt it as an adult when I needed it. I like languages, though, and I spend a good deal of time in perfecting my English (perhaps I should use some of it to get some electronics skills, hehe). Well yes, sorry. I started two different threads, actually I only started this one about the monitors, and followed on a different one about recovering old Sun servers which derived to using terminals with them. Somewhere along the discussion, someone (sorry, I can't remember whom it was) said that the Sun box would redirect to the serial console if it didn't find a keyboard attached to it, and then I brought up the Ampex problem I'm trying to solve too. Sorry about the mess I'm making, hehe. LOL. I'm sure he will. By the way, Tony is one of the guys a envy the most. I really enjoy reading hist posts about fixing and using cool pieces of equipment. I think he's also a kind of "walking encyclopedia". :-) They are very cool, yes. I've got another Sun monitors which I'm using at the moment, but they aren't even close to the GDM-20D10s. Thank you, that's a relieve. As I said before, I haven't been into fixing hardware. I'm usually more interested into recovering it (mainly Sun), cleaning it, and making it work, usually with either OpenBSD or Debian GNU/Linux. But it'd be said to not be able to recover those monitors. That's what I enjoy the most of this (and other) lists. Even when I don't contribute a lot, I read them and follow some discussions with interest. You're totally right. I was hopping somebody would jump in and say he's had the same problem and there was something like a fuse or something I could very easily change myself... Hoping is cheap, isn't it? :D It'd be great if that was the case. Or if I was in London and I could bother Tony with that in person, LOL. But I'm afraid it isn't going to be possible, since I'm in the south of Spain. :-) One of your suggestions was for me to hold onto the monitors until I can fix them or get them fixed for me, and that's the only think I'm doing for the moment, apart from troubling you guys with it and my incompetence. :D Angel -- Angel Martin Alganza Departamento de Genetica, Universidad de Granada Full contact data at http://www.ugr.es/~ama/ PGP Public key at http://www.ugr.es/~ama/ama-pgp-key ------------------------------------------------------ () ASCII Ribbon Campaign - http://www.asciiribbon.org/ /\ Against all HTML e-mail and proprietary attachments Please avoid sending me Word or PowerPoint attachments http://linux.sgms-centre.com/advocacy/no-ms-office.php

The only way to learn is to 'have a go'. Yes, you need to learn some electronics from books, but in the end you have to start tryign to figure things out for yourself, on the actual hardware. I don;t want ot put you off, but I've been repariing classic comptuers for nearly 30 years now (started doing it seriously in 1986), and I am certainly still learning. In fact I don;t thinkyou ever stop learning on soemthing like this. I am not convioncd a mnoitor, particularly one with what sounds to me like a power uspply fault, is the easiest thing to learn on, but then again I wou;dn't pick the PDP11./45 as the fisrt minicomputer to get going, but it's the one I learnt CPU repair on. Sometimes you are forced to work on thigns that wouldn't bee the first choice :-) There may well eb a service manual availabe for this monitor, Sony were pretty good about producing them. I ahve no idea where you'd get it from, and it'll be written for service technicians, it won't be a 'handholding manual'. Most likely it'll be the schematics, PCB layouts, parts lists and n ot a lot more. Votlags nd waveforms may be given on the schematcs/ I could say something like : " I am guessing there's no sign of life at all when you turn them on (no power light, the CRT heaters don't glow, etc). In which case this sounds like a power supply problem. I am going to guess it's a switch-mode PSU. Check the mains fuse and see if it's blackened (indicating a catastrophic failure of the PSU) If not, elimineate the 'silly fault' by making sure the on-off switch cloeses correctly. then suspect the startup resistor, a high vlaue reisstor from the positive side of the mains smoothing capacitor to the chopper drive circuitry." The problem is that while that's what I would do, I doubt you'd be able to find thos componetns without more information and woulnd't know how to trest them, or repalce them. -tony