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schematic for Color Classic analog board?
- Thread starter mraroid
- Start date
Not available
Gez! How can I or anyone figure out a *real* 640 X 480 mod for the Color Classic then? I think if i understood the analog board, I could beef up some components and make a safe upgrade with out over driving anything past it's designed parameters.
Someone must have drawn one out to do the Hi Rez and the VGA upgrade.....
I love my Mac equipment, but I have to say I think the Color Classic service manual is crap. It looks like it was made for children. No schematic. How do I stick my 'scope or VOM into it and look at a schematic and figure out how to trouble shoot it?
Is all of this because of proprietary stuff in the early days of computers? Did Apple not want anyone to steal it's designs so none of this stuff was ever published?
I mostly work on old time 1930s-1950s vacuum tube amps and old radios. Schematics were usually stuck in the amp or radio so if you ever needed to fix them, you have a schematic in front of you.
Perhaps early computer stuff was secret...... I admit to not knowing this computer world.
Woops! I see I have gone into rant mode. Apologies all around. Please forgive me.
I still wish I had a analog board schematic.
jack
Someone must have drawn one out to do the Hi Rez and the VGA upgrade.....
I love my Mac equipment, but I have to say I think the Color Classic service manual is crap. It looks like it was made for children. No schematic. How do I stick my 'scope or VOM into it and look at a schematic and figure out how to trouble shoot it?
Is all of this because of proprietary stuff in the early days of computers? Did Apple not want anyone to steal it's designs so none of this stuff was ever published?
I mostly work on old time 1930s-1950s vacuum tube amps and old radios. Schematics were usually stuck in the amp or radio so if you ever needed to fix them, you have a schematic in front of you.
Perhaps early computer stuff was secret...... I admit to not knowing this computer world.
Woops! I see I have gone into rant mode. Apologies all around. Please forgive me.
I still wish I had a analog board schematic.
jack
the guy who figured out the 640x480 mod, I have no idea how he figured it out. Maybe it came from an internal apple employee, or repair guy. Hard to say.
One of these days... when I get time... HAHAHAHAAHA.... I need to go through and compare the two analog boards and figure out the differences.
That guy that developed this mod is Chris Lawson. He developed the VGA mod and posted it in Aug 2001. Here it is:
http://colourclassicfaq.com/general/vga.html
Chris and I have crossed paths in the past, but it must have been at least 10 years ago. So I shot him some email asking if he had or knew where to buy a analog board schematic. He said he has never seen one, but maybe the Japanese have one, but he would not know where to start looking. I asked a few technical questions, but as he did this mod 14 years ago, he really could not pull the numbers out of his head (I know I could not).
So, with no real data on the VGA mod, I am going to do this:
I am taking the analog board from a Performia 575 and cutting it down to size so it will fit in a Color Classic case. In a Performa 575 the 575 logic board and the analog board were used to drive a 14 inch sony trinitron CRT at 640 X 480. I will over clock the 575 logic board and then do a software hack so everyone is happy. After that, my color classic will not be driving any components outside of it's designed range. Also, after a logic board and a analog board re cap, it might add a few more years to the Color Classics's life. Also, if I roll in a SCSI to CF or micro SD card solution like this
http://www. codesrc.com/mediawiki/index.php?title=SCSI2SD
or this
http://www. ebay.com/itm/CF-AztecMonster-CF-3-5inc-SCSI-Converter-Card-New-Condition-for-AKAI-E-mu-/301642978341?
http://www. artmix.com/pdffiles/CF_AZTECMONSTER_MN_E_13.pdf
I will draw far less current (less demand on the power supply) and the entire computer will be much cooler. All mechanical hard drives are anyway are 120F to 150F heaters that we put in our computers. Heat is not our friend. But heck, maybe I will end up liking a modern fast SCSI HD in the end.
Has any one here done the 575 analog board mod in a Color Classic? I would like to chat with someone first before I do something stupid. Here is the mod:
http://www. fenestrated.net/~macman/CC575/
jack the new kid
Yikes! That alone is enought to talk me out of it. Thank you for posting that info.
jack the new kid
47Hz: which makes sense, in order to bring the line frequency back into the correct range, you have to lower the refresh rate. Higher refresh rates require a faster beam to scan the picture, which is a higher line frequency.
