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I need to get the system working first, though :-/

My oscilloscope arrived!

When I first turn on the machine I get this: If I toggle the power, I get this: I have the C4P hooked to a Samsung LED TV. No colour is coming through.
Your thoughts?

/Jeff

HI All, I have an unhappy C4P MF that needs some fixing. So far I have re-seated all the chips on all 4 boards but all I get is a video signal, no prompt when pressing break (with shift-lock down) for more than 3 seconds. I have measured the voltages from the 2 power supplies. The one that feeds the...

Thanks for the tips! I do have a DMM I will start a new thread.

Cheers

/Jeff

Hi Dave, What I find curious about this board is the 24K of RAM! I sent you a component layout with all the chip numbers. I have downloaded the data sheets for each of the chips on this board and will start to trace the circuit. Any thoughts on the 24K? Do you think it is video ram? Or do you think ...

I posted the large images to Photobucket. 541 board http://i1056.photobucket.com/albums/t361/chaosdesignsG5/OSI%20stuff/OSI541top_zps73926f02.jpg 540 board top http://i1056.photobucket.com/albums/t361/chaosdesignsG5/OSI%20stuff/OSI540top_zps61417f74.jpg 540 board bottom http://i1056.photobucket.com/...

Hi Dave, Thanks for your reply. I did some more investigation last night and discovered that the story isn't complete without examining the 540 video board. The chargen was removed from the 540 and transplanted onto the 541. A 24 pin cable connects from the chargen socket on the 540 to the 541. Also...

If anyone has a dead C1P I would be interested in purchasing it. Reasonably good cosmetic shape is important. Thanks for looking.

/Jeff

Here is a photo of my 541 board.

WOW! Beautiful!!!!

/Jeff