4724 Views 7 Replies Latest reply: Nov 15, 2010 6:23 PM by Martin Stevens
The rocker switch on most of those old unibody Macs is a service switch. It must be on for the unit to operate, but does not start it up. The other term used is "soft power". You need the power key on the keyboard to fire it up. Any adb keyboard will work. The key in question has a left-pointed triangle Icon.
I turned it on an it made a sound like a power supply charging up.
That's Good. That's the sound of a working unibody Mac power supply.
Is there a battery on the motherboard?
There is a PRAM backup battery. It is likely to be 1/2 AA sized, and must be 3.6 Volts new, 3.2 Volts or better to work. A 3.0 Volt camera battery will not suffice.
I resurrected my old PM 7600 a few weeks ago after five years in the basement, boxed. Replacing the PRAM battery is essential. I found the battery at Radio Shack for something like $10...pricey but the voltage has to very close to 3.6v as Grant says. Good luck getting the machine working...surprising how well and how long they will function.
If it is like most of the other unibody Macs, you need to remove the two Torx screws deep inside the top handle. I think there must be at least two more. They can also be removed with the proper Torx driver, or fudged with a near-fitting American-sized Allen (hexagon) driver, as they are only into plastic.
The two case halves are press-fit together (not a hydraulic-press tight -- the screws draw them together). The challenge is to coax them apart without gouging the plastic. Don't even think about using a screwdriver -- it will definitely gouge the plastic. Aftermarket vendors used to supply a 3 inch wide Bulldog clamp to insert in the crack between the halves and squeeze open. A wide putty knife may be useful, but go easy.
The extremely delicate neck of the CRT must be treated with special care. There is a slender capillary tube there, used to remove the last traces of gas from the tube. Break that off while pulling at connectors and your CRT is instantly landfill.
Also, it is possible for the CRT to store over 10,000 Volts for decades. The CRT bottle itself, the Big Red Wire, and the Flyback transformer may store this Voltage. Connect that through your Heart, (e.g., Hand-to-Hand) and it can literally stop your heart.
Thanks Grant, good safety pointers, googled some excellent PDF manuals on the color classic, mother board slides out easily like a PCI card (very innovative feature for the times) by removing a cover on the back so you do not have to crack the case, pram battery cover tricky to remove but manual showed exactly how.
Keep up the good work
I disassembled the color classic and thoroughly clean out all the dust, all components are working perfectly except the hard drive is dead besides original owner wanted to keep it. It boots the tools floppy disk perfectly but I need a hard drive to load the OS. It had a "Conner CP30085E 85MB 3.5in SCSI 50PIN". Do you know of a source where I can find this drive or another drive at a reasonable price that would work. I did find one at d-c-p.com but very pricey at $249. Also is has OS 7.1 floppy disks is there a later system that would work.
Something like this will be fine for you:
The Colour Classic can be upgraded up to OS 7.6.