Recent content by WhoaMan

as do i, i was surprised to find that the computer was actually in the box. I got the system up and going last night, recapped the analog board with some Rubycons and the logic board with some surface mount tant caps. Before recapping, the analog board was putting out around 4.2 - 4.5volts on...

In between hanging out with all the mothers in my family and my sister in law's birthday party, I took a load of 42 computers to the local PC Recycle center. Once there, I started unloading my surplus on to one of their trailers. After a few trips back and fourth between my trailer and theirs, I...

U1G, U3G, U2F, and BMU0 should be the silkscreen markings on the logic board. VA13 and VX13 are the signal names, i am guessing that one of the two will be stuck low ( 0 volts ). You might want to check the pin numbers mentioned on those parts for any loose or bad solder joints or shorts (an...

Alrighty, lets pretend we are showing a res of 512x384... and at 1bit per pixel, this leaves us with a video buffer size of 24kilobytes... lets divide that buffer by 3 (since you have three sections showing on your screen) , this will give us an 8kilobyte chunk... assuming we were running with...

Cap stuff.... as in the capacitors were leaking? If they have leaked at all, you will want to replace them before going any further in your troubleshooting as it will make the system unstable, and to be honest, could be creating all of your issues

When you boot it up with just the mouse connected... and it shows the main (but frozen) desktop... does the time and date appear to be correct? if not, is it always the same date and time when it reaches this point? If you have no floppy in the drive and disconnect the hard drive, do you get...

You said the board was re-capped an resoldered? did someone go over to correct some cold solder joints or something? or was it just a re-cap? what brand and series did they use for the recap? Out of curiosity, do you happen to have an external scsi drive you can try with the internal disconnected?

After toying around with the simple EGA video out stuff, I started thinking about bench testing/troubleshooting for the compact macs. Would anyone be interested if i were to design, test, and publish gerber files for a troubleshooting board for the 128/512/plus? I figure the device could be used...

After taking a look at the schematics for a few minutes, I would suggest checking out the 4 74253 mux's. for problems. I assume UF8, UG6, and UG7 are working correctly as the system is getting its vblank and hblank signals. I also assume UE8, UC6 and UC7 are working correctly as UE8 (shift...

just to make things easier, here is the link. i believe these were the ones you are talking about? https://docs.google.com/open?id=0B3mQLg8d1xThNzQxMTA5ZGQtNmNlMy00MWUwLTg3YWMtMmE3MTc3ZjQxZTYz

how much memory does your se/30 have? what size and location are each of the SIMMS? it sounds to me like one of your paired SIMMS has died or needs to be reseated.

zuiko21, most people would want to use set sw-hselect and sw-vselect to use the outputs from the 7404. The only reason i added the ability to switch between /hsync and hsync has to do with a few arcade "CGA" monitors that I have sitting around... just in case i decided to hook it up to a bigger...

I apologise, the monitor is actually an EGA monitor and is running in EGA mode due to the negative vsync. I do have to admit, I am curious as to what would happen if i inverted vsync and tried it in CGA mode, maybe I will have to try that out sometime tomorrow on both this monitor and another...

Recently, I got a Mac Plus board from a member of these forums for a project that I am working on. I am not far enough in this project to where I need the board, but figured it would be nice to have on hand for when I am ready... and decided to play around with it in the meantime. Since I just...

Lately, I have been working on a new project. I want to design and build my own 68K MAC clone, based off the Mac Plus and Mac Classic. I plan to keep the general memory layout the same, dividing the 16meg memory space in to 4 sections and their general assignments, also i plan to use 4mb of ram...