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Dead PRAM and Mouse Speed Setting

MultiFinder

Well-known member
I remember when that happened to MF17, he was on IRC and he started "Screaming" lol, it was funny.
That's not very nice, he could have died then! :p Those little compacts sure look sweet but they have a vicious bite if you get on the wrong side of them...
Bah, I was fine. It sucks to get stung by a compact CRT, but it's not horribly bad. My arm tingled for about an hour afterwards :p

 

coius

Well-known member
discharge the CRT

http://www.biwa.ne.jp/~shamada/fullmac/repairEng.html

You can do that with a BIG screwdriver and attach a big alligator clip to the pole of the screwdrive. If you hear a LOUD CRACK, it's that you have discharged the CRT, do it 3x to make sure you have discharged the CRT. after that, the only thing you have to worry about is knocking the back of the CRT killing the tube

 

phreakout

Well-known member
Macster,

I'd be more afraid of breaking the CRT than getting jolted. Most of the harmfull energy is disspated when you turn the computer off. If you let it sit a few minutes before unplugging power, it will be safe enough to work around without getting shocked. Another thing you could do is turn the brightness/contrast setting up all the way and unplugg the Mac. This will force all the electricity in the tube to drain off.

Patrickool93, do you remember what was said by MF17 when he was zapped? [:eek:)] ]'>

73s 8)

 

iMac600

Well-known member
iMac600 grips anode cap and switches power on

:p ;)

Seriously, i've heard it's not as bad as first thought, but it can be, depending on the type of CRT.

Once I shoved a metal screwdriver in to my CRT just after it had been switched off to reconnect one of the ADB cables (ADB hub built in). Walking the thin line between life and death, let's say I successfully made the reconnection but the monitor died soon after from Analog Board failure.

 

Maniacintosh

Well-known member
I wuldn't think the shock from a Compact Mac's CRT would be that bad; the flyback transformer "only" supplies 15kV or so, compared to 30kV or more for a 15" color monitor.

 

Scott Baret

Well-known member
I use insulated pliers to pull out anode caps. I've never seen anyone else use them, they're sort of my trademark when I do CRT work.

The PRAM battery on a Classic is easy to access. If you want a challenge try an SE.

 

MacMan

Well-known member
Knocking the back off a CRT won't make it implode, but it will render it dead. A friend of mine who works in an electronics store has the job of knocking the back off the CRT's of old TVs before they get sent to the dump, so they won't implode in transit. He has to deal with CRTs which are normally 20" and above in size!

 

Big Bird

Well-known member
I don't suppose you know how to make a Network Time control panel for 68ks (was it not until OS9 that this was introduced?) that syncs the clock when you start the machine up? I guess that would be difficult though. A way to get rid of that annoying dialog on OS9 that pops up when the desktop loads telling your clock is wrong would be nice though...
Pete Resnick has written such a program, called Network Time. It is compatible with System 6.0.5 and later, through System 7.

From the author:

Network Time is a control panel program that sets the clock on your Macintosh computer to the correct time of day. To do this, Network Time contacts a time server using the Apple MacTCP network software to get the correct time of day. Network Time automatically adjusts your clock taking into consideration the time zone and the daylight savings time rules that you configure using the Network Time control panel.
Network Time requires at least a Macintosh Plus computer running system software version 6.0.5 or later (including System 7) and requires MacTCP version 1.1 or later. Network Time has full Balloon Help support. Foreign language versions of Network Time are available separately; the versions that are now either avaiable or in progress are Chinese, Dutch, French, German, Japanese, Russian, Spanish, and Swedish.

This package contains a QuickStart manual with basic instructions in TeachText format and the full Network Time manual is provided in MacWrite Pro format. The manual is also available in PostScript format in a separate archive, and a printed copy of the manual can be obtained from the author.

Network Time is a shareware program. Please send US$5 per copy or US$100 per 100 copies of Network Time, and US$5 per printed manual (along with any questions or comments) to:

Pete Resnick

1009 North Busey Avenue

Urbana, IL 61801

(217)337-1905

You can also send electronic mail via the Internet to:

resnick@cogsci.uiuc.edu.
Download it here: http://hyperarchive.lcs.mit.edu/HyperArchive/Archive/comm/inet/network-time-201.hqx

 

equill

Well-known member
Soldiers! This is an army, innit? You know. Danger. Risk. Bitey things. The remedy is to approach danger knowingly.

First know that the totally undeserved reputation of Classic monochrome AIO Compacts as marauders, killers and tax evaders is a furphy. If you crank up the brightness while the Mac is operating, and pull out the mains plug without turning the Mac off, the charge on the CRT goes pfffft! instantly. If you have an SE FDHD or later it has bleeder circuitry to achieve the same purpose after switchoff. This may not be working, however, so even leaving the Mac switched off overnight, but still plugged into the mains, will dissipate much of the charge on the CRT.

The constant injunctions about the CRT in the Service Source manuals are Apple's lawyer-talk, to protect not you, not the CRT, but Apple. When tomlee59 puts up his sticky about the amount of charge and the ways in which you can avoid being its groundpath from the CRT, you will be able to treat the compact Macs with knowledgeable respect, not fear.

You can believe that tomlee59 knows what he writes about, by practice and profession.

de

 
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