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| Thread ID: 29811 | 2003-02-03 23:29:00 | Monitors | B.M. (505) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 118011 | 2003-02-03 23:29:00 | Having bathed in the success of having made huge improvements to an old Monitor by following Billy T’s instructions on how to adjust the focus, along with Eric’s Monitor tests, I’m ready to move on to bigger and brighter challenges. I’ve found another old monitor that needs some colour adjustment. I’ve also found three little variable resistors on the PC board the CRT plugs into. Now, with Eric’s colour bars on screen I find one adjusts Blue, one Green, and one Red. (Surprise surprise) So, the question is what is the correct sequence of events for aligning a Monitor? Unfortunately, I no longer have access to twin beam oscilloscopes, signal and pattern generators etc.etc. Just a test pattern courtesy of the internet, and a couple of multimeters. Therefore, I’m looking for some good, old-fashioned, seat of the pants technology. :) |
B.M. (505) | ||
| 118012 | 2003-02-04 00:25:00 | There's enough reading matter on this site about monitors to keep you out of mischief for hours and hours Bob. www.repairfaq.org |
Terry Porritt (14) | ||
| 118013 | 2003-02-04 00:31:00 | Oh. also forgot, if you go to Simtel, there is a good selection of vga test utils. Svgat350.zip has a Philips test pattern which is excellent for setting up and adjusting the colours. www.simtel.net |
Terry Porritt (14) | ||
| 118014 | 2003-02-04 02:47:00 | Thanks Terry, Excellent Site, I printed out all the instructions for future reference, (A small book) so the next thing I’ll be looking to fix is the printer I guess. What intrigues me is that these Monitors that I’ve been playing with were en route to the rubbish dump when they were "intercepted". Sure, they needed some adjustment, but they are relatively new and I suspect some of the components have only just settled down. Guess nobody fixes things anymore? |
B.M. (505) | ||
| 118015 | 2003-02-04 15:52:00 | Would you like any other patterns ? maybe red & blue crosshatch just for company for the green crosshatch Maybe I could put together a ZIP file so you could download it, unzip & burn your own self loading CDROM pattern generator. From Eric |
E.ric (351) | ||
| 118016 | 2003-02-04 19:45:00 | E . ric, in my travels I found this site, which has a test pattern developed by Nokia . . freepctech . com/rode/004 . shtml" target="_blank">www . freepctech . com I’ve thrown it in a folder with a shortcut on my desktop so I’ve got an instant pattern generator . My problem now is establishing a “basic” procedure for the “basic” alignment . Today’s little project is re-soldering a dry joint on the pc board the CRT plugs into . (Yep, I found a genuine fault) Problem is de-soldering the metal screen on the back of the board . Don’t know what the manufacturers thought they were doing, but there’s more solder holding it on than they used on the top radiator tank of a ’39 Austin 7! :D Out with the gas axe! :p Bob |
B.M. (505) | ||
| 118017 | 2003-02-04 21:51:00 | Just a quick note You adjust the backgrounds controls on the black part of the picture (use gray scale) Then adjust the Highlights controls on the white part of the picture, Some models only have two controls for this adjustment. Sometimes I found it is better to turn the blue down and adjust red & green for yellow, then adjust the blue for white. |
E.ric (351) | ||
| 118018 | 2003-02-04 22:42:00 | Thanks Eric I’ll try that later. In the meantime I’ve managed to remove the metal screen/cover on the PC board that the CRT plugs into and revealed some of the worst soldering I’ve ever seen. There might have only been one dry joint causing the immediate problem but there are heaps of others, which are potential problems. Guess I can spend the afternoon re-soldering the whole board! A lot of the problem appears to be cheap solder which seems to have crystalised?! :( |
B.M. (505) | ||
| 118019 | 2003-02-05 04:50:00 | Just be glad they didn't use the NZ made stuff (from the 70s?) which (to save importing lead) was made with recycled lead from car batteries. It might have been OK for plumbing, but for electronics ... :_| The electronics assembly companies (remember them?) had major problems. The Post Office didn't; they refused to use the stuff. There are various sorts of lead-free solder being tried because lead vapour is not terribly healthy. Unfortunately, 60-40 tin/lead still seems to be the best for soldering, though a bit of copper, and sometimes silver added may make it better. I'm happy I've still got a few kg of genuine Multicore ... that should see me out. :D |
Graham L (2) | ||
| 118020 | 2003-02-05 05:00:00 | That stuff was awful, guaranteed to produce dry joints ! The Multicore Savbit tin/lead/copper you can get from DSE is ok, in fact quite good, but their own DSE brand ordinary 60/40 isnt very good. | Terry Porritt (14) | ||
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