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faroZ06

macrumors 68040
Original poster
Apr 3, 2009
3,387
1
I know that this is the iMac section, but there is no "pre-PPC" Mac section, and I figured that the Mac 512k is closer to an iMac than anything else.

Since the Mac 512k is from 1984, I'm worried about lack of radiation shielding on its computing parts. I heard that unshielded CPUs can give off harmful radiation. Do these things lack proper shielding, or was that back in the 70s?
 
You've just reminded me of a scene in Superman III where the black guy trying to enter into an office tells the security guard he needs to go in because one of the computers has a radiation leak. ;-)
 
The only radiation that CPUs give off are heat and, sometimes, depending on speed, radio waves. They don't give off anything like gamma- or X-rays. The 512s can't harm you, but they could suffer from heat damage; they really should have had a fan.
 
Yes it does but only a little bit. I think I read that you would have to spend over 2 hours a day in front of it for more than a month before you experience any radiation poisoning.
 
You know, those of us who used CRT's and CPU's from the '70's are dying off...but we are getting to that age. ;)

"I heard" doesn't constitute truth. Stop worrying about things that you need not fear. The car on pictured on your profile is faaaar more dangerous to its driver and passengers, as well as to the environment, than any computer ever developed.
 
I know that this is the iMac section, but there is no "pre-PPC" Mac section, and I figured that the Mac 512k is closer to an iMac than anything else.

Since the Mac 512k is from 1984, I'm worried about lack of radiation shielding on its computing parts. I heard that unshielded CPUs can give off harmful radiation. Do these things lack proper shielding, or was that back in the 70s?

I'm curious as to what you're planning to do with the 512. It's not as if there are enough practical applications to warrant running it much, assuming it still works. Floppies might be tough to find, too. :)
 
I'm curious as to what you're planning to do with the 512. It's not as if there are enough practical applications to warrant running it much, assuming it still works. Floppies might be tough to find, too. :)

Actually, the floppy drive is slightly broken :(

But the diskettes are not hard to find. My dad has a big collection of them, and the external USB diskette drive from my 1998 Sony VAIO works with my Mac (but not with my VAIO, ironically). I can read and write to/from diskettes.
 
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As I remember if you remove the case be careful touching things around the CRT.

There is some kind of capacitor for the CRT that can shock you with high voltage and supposedly cause harm, but I'm doubtful of that since a lot of current would also have to be involved. Static electricity from rubbing your socks on a carpet is very high voltage but still not harmful.
 
There is some kind of capacitor for the CRT that can shock you with high voltage and supposedly cause harm, but I'm doubtful of that since a lot of current would also have to be involved. Static electricity from rubbing your socks on a carpet is very high voltage but still not harmful.
I found this warning which is also applicable to the earlier all-in-one Macs.


I. Disassemble the Mac SE/30 Box

1. Caution and Warning

Before working inside the Macintosh SE/30, turn off the power and disconnect the AC power cord.
The SE/30 contains high voltage (1,500 Volts), a high-vacuum cathode ray tube (CRT) and sensitive electronic parts.

To prevent serious injury, the first thing you have to do is to discharge the CRT. Discharging the CRT before working on it lessens the chance of an electric shock.
Some later compact Macs containing CRTs have a bleeder resistor on the anode that drains the charge when the power is turned off. However, if the resistor fails, the anode may retain a charge. Thus, you must perform the discharge procedure.
Never touch the anode connector or the anode aperture, that can regain some charge even after it has been discharged.

Secondly, you must be careful not to break the fragile CRT neck. Do not pick up or handle a CRT by its neck, where the tube is the thinnest. To prevent an implosion, take every precaution against breaking the CRT. Wearing safety goggles is preferred when working with a CRT. The CRT contains a high vacuum. If cracked or broken, the CRT can implode (collapse into itself) and scatter fragments of glass.

Thirdly, precautions are required not to break IC and LSI chips on the board by electrostatic damages.

Go ahead at your own risk. Nobody can take responsibility for you.

:eek:
 
I found this warning which is also applicable to the earlier all-in-one Macs.


(snip)

Go ahead at your own risk. Nobody can take responsibility for you.

:eek:

I'm not worried about risks when the computer is open, and I'm aware of the danger of tampering with CRT components. I'm actually surprised that the static electricity on the CRT does not interfere with the computing parts on PCs.
 
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