Hi,
i just collected an Gould K50 Logic Analyzer from my Uni's trash. Which, well, doesnt work, no picture displayed.After discovering a "Comp. Video Out" BNC on the back side and connecting a regular PAL TV to it, i got a picture, and could confirm the analyzer part works fine. Just the monitor doesnt.Its a small (6"ish) monochrome (probably green or amber) raster scan monitor accepting a BAS composite signal (probably PAL, or at least similar).It rund off 12V from the large main power supply, which is okay.
Now for what i found, after looking at the monitor PCV for some time i identified a burned 1/4W resistor (R9).Its completely burned, no color code to see anymore.Being mounted a few mm off the board (the only resistor to be mounted that way) it could well have been a fuseable resistor. Now for its environment, its connected in series with D7, a BA159 Diode being connected to one of the many line output transformer pins.The other side goes to 2 unsuspicious 630V film capacitors and a red wire going to the CRT socket, but also to one of the many ceramic thick-film circiuts in there.
Now, having a shematic would be great, but KME denys any knowledge of ever having made a MB11 Monitor, and if they would, they wont give out any service info.Great.
Does anyone have a remote clue of the resistors probable value? Id think of something in the 10Ohm-ish range...
Also, im fairly sure the problem is somewhere else and it will burn up right after replacing, but after testing all testable semiconductors (thats all, except the vertical output IC and the 6 thick film hybrids) i coundlt yet locate any other fault.
Does anyone have any service information on this or any similar monitor module?
If all fails, i guess i will somehow fit one of these small LCD monitors designed for car use in there, which certainly isnt a very good thing and will look ugly.
Regards, Robert