CRTs and whatnot

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CRTs and whatnot

Okay, at the risk of sounding completely stupid, here's a question - I'm interested in doing the iMac into colour classic hack, am comfortable with electronics but live alone and am terrified of zapping myself with the CRT. What's the safest way of dealing with this - my old electronics teacher used to tell me that they were _very_ dangerous and I figured I just wouldn't work with them. Guess I should have paid a bit more attention, eh?

Semi related - have you seen this: http://thinksecret.com/news/0412expo2.html - if it's true, and small enough, it might be the way to high power G4 CCs.

I've also considered using a Wallstreet Powerbook board and an LCD screen running off the VGA output (I have two of those powerbooks), but somehow it seems a waste of a viable machine - the iMac route seems the best. Any tips would be appreciated.

Cheers

Mike

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Re: CRTs and whatnot

Obviously, you should take the normal precautions and read the FAQ for this forum which should adequately answer your concerns.

My experience is that after a goodly amount of time with no powered applied to the components, you should be fine.

Based on my experience, a sub-$500 system, while possible, is not in Apple's future. Additionally, I don't think it is in Apple's best interest. They've built a reputation of reliable hardware and software systems (okay, not counting a few OSes and a few Road Apples). There are plenty of sub-$500 systems out there that can be had, such as the iMac, that with minimal upgrades will operate at a decent clip.

IMHO, YMMV.

Jack

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I hope it's true...

... because it would be hugely successful. And it's eminently doable for less than $500. Look at the eMac, which retails for $800. Drop the CRT — which simplifies the construction and eliminates a lot of bulk and expensive componentry — and you could end up with a slim little package that hits that magic number.

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Discharge the CRT and you sho

Discharge the CRT and you should be fine. Personally, I would be more worried about the low freq / PSU caps. The high tension stuff is pritty unlikely to kill you. (But it still can)

P.S- Apprently someone died from doing a resistivity test with a digital mulitimeter, to work out there internal resistance. They stuck one probe into each hand...

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Thanks

I missed the part in the FAQ about CRTs and when I went back to look found them. The bit about bleed resistors makes me much happier - as I mentioned, I live alone and really didn't want to have my imac in cc project end with the neighbours complaining about a funny smell and talking about how I wass such a nice man.

Now, to find a semi dead iMac.

Cheers

Mike

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I suggest you wear plastic gl

I suggest you wear plastic gloves, as sweaty hands increase conductivity...

Oh bleed resistors can fail ;), so discharge it anyway...

When I dismantled my iMac's crt, I got a tingle from the power supply board...so be careful. That was probally from a lower voltage capacitor...

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I use a long hook tool to rem

I use a long hook tool to remove the anode cap and I ground the cap and tool to the CC crt ground wire that wraps around the CRT while the power is plugged into the CC but the switch is off. That way the machine has no power but is bonded to ground. Once the anode cap wire is grounded and bled off, you are reasonably safe to do about what you want to with the board. If you are still freaked out, then ground out all the pins on the flyback transformer before you do your work. I have been shocked by a CC when it was on and it hurt like a mother but it moves you away from the machine, not into it. That was my experience anyways. Biggrin

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Keep one hand behind yer back . . .

when ever you have to go near dangerous stuff. Makes it much harder to kill thyself.

dan k

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