Re: Intermittent fault in Eizo 19" T766 CRT



"bz" <bz+ser@xxxxxxxxxxxxxxxxxxxx> wrote in message
news:Xns9A8BDA027CCDCWQAHBGMXSZHVspammote@xxxxxxxxxxxxxxxxx
E"James Sweet" <jamessweet@xxxxxxxxxxx> wrote in
90vQj.50$5X.10@trndny08:">news:90vQj.50$5X.10@trndny08:

You shouldn't have to discharge the CRT, that's only necessary if you
have to remove the anode lead, even then it usually discharges itself
through the focus divider on color monitors.

Caution: even if you discharge the CRT, if the anode lead is disconnected,
as the dielectric (glass in this case) 'relaxes from the stresses of being
charged', a charge can build back up.

I can remember drawing a nice arc many minutes after discharging the tube
the first time.

This can be a bit of a surprise, especially if you are removing the CRT to
replace it. Shocking, one might say.

Also, the comment about letting it sit for 10 minutes so all the
capacitors
will be discharged is good, assuming that there are no open bleeder
resistors, etc. But, it might NOT be good to 'bet your life' on the
bleeders doing their job. Occasionally, they do open, so your caution to
treat them as if they might be 'live' is a good one for those that want a
long life.



Yes if you disconnect the anode, you should definitely discharge it again
before you touch it, I usually leave a clip lead connecting it to the ground
strap so that doesn't happen. The zap won't hurt you, but it's enough of a
surprise to drop the thing or cut your hand open. In this case he shouldn't
have to disconnect the anode though.


.

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