scott@cs.odu.edu (Scott D. Yelich) (06/24/91)
Hello? I know there are people out there, I see YOUR posts... Thank you J. R. Bammi for replying to my query about the capicitor that needs to be replaced in the mono monitor. JR told me to look for a completely fried capicitor... well, I am using my mono monitor now. I have decided to leave my monichrome monitor on until the capicitor blows because no one else has replied as to which one it is. IS IT THE 220uF which is rated at 16V what is on the power board? If not, hell, there are hundreds of capicitors in there. ------------------------------------------------------------------------------ Next point of interest-- Hello? Has anyone ever installed the overscan mods into a 1040st Hello? This is what the doc says: How to connect and wire the Overscan-change-over-switch: Directly at the Emitter of the Composite Sync signal driver Transistor You pick up the buffered Composite Sync Signal and feed it to the third pin of the switch. The second pin of the switch (the pin in the middle) goes to the pin 37 of the Shifter and pin 52 of the MMU. The first pin of the switch is connected to pin 39 of the Glue (Display Enable Signal) Reminder: the MFP 68901 pin 20 still gets the Display Enable Signal in both modes !!! We have tried to use also the Composite Sync for the Timer B-Input in Overscan mode, but then the ST doesn't boot himself after a Reset ! Now, I think I can figure out WHAT needs to be done, but alas, I don't know the "where." I do not have a schematic of the 1040 and the digitized images with overscan all appear to show the 520 (with RF) upgrade which I thought the docs said required more hardware. From what I gather, all I need to do is locate: 1) A two position switch (3 pin). 2) DEs from shifter pin 37. 3) MMU pin 52 both 2 and 3 go to the central pin of the switch.... 4) pin 1 of the switch goes to pin 39 of the GLUE (DEs?). 5) pin 3 of the switch goes to Composite Sync. I don't know which chips are GLUE and MMU.... Or where the composite Sync is. I will try to inspect the chips a little closer after this post goes out. What was all that about messing with the hsync and vsync of the monitor? I put electronic tape down the shaft of a long screw driver in preparation for this upgrade, but it looks as if it all is done inside the ST. Does one have to mess with the H/V sync, or whatever, inside the mono monitor? At least those parts are clearly labelled. Hey, if you know anything about this, please don't assume someone else will reply. So far in six months of posting questions here, I have received replies from three people... none of which have been complete. Please let me know if you have done this mod. One last note, from what I read in the overscan docs, it looks like it explained a problem my color monitor has.... when I turn up the contrast and brightness level all the way (the only way I can get to see most of the colors) the back of the screen is no longer black, it is an off red-brown and I get these ugly diagonal lines that look like scan lines... .but they are different, they run from the lower left to the upper right... I would guess that there are like 10-20 of them. THey don't move, but they are definitely there. The docs seem to suggest that these are verticle blank "flyback" traces. I was under the impression that during the verticle blank time, there was no display signal, so there would not be and "loose" traces..... Does anyone have any ideas about this? It's really annoying since I need to turn up the contrast and brightness levels all the way just to be able to see some text and colors in most programs. HELLO? "Is anyone out there?" Scott