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Old 10-02-2015, 12:18 PM
Electronic M's Avatar
Electronic M Electronic M is offline
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You should get an HV probe to use it to discharge the CRT, and confirm HV reg is adjusted properly once you get it going. If you use an HV probe, the CRT second anode should not 'recover' any voltage, and you get to see that it has discharged to a safe voltage. Just clip the ground lead of the probe to the chassis, hold probe by user handle stick the tip on it's far end under the HV suction cup or to the plate at the base of the HV rect tube if more convenient, and watch the needle jump and fade back to zero.

Honestly, if you are wearing rubber soled shoes and not touching any metal that leads back to the chassis you could touch the HV lead with the set off and it would not be much worse than a static shock from shuffling your feet across the carpet and grabbing a door knob.....If you change that situation to holding the handle of a large insulated screw driver with the metal tip touching the HV you should feel nothing since there is far too much insulation for current to flow thru you even if the ground jumper were to fall off.

If the CRT has not lit for you there probably is no or very little HV.

I can understand being a bit squeamish after a jolt, I've had enough of them to know (99% were reconnecting the lead after the screw driver discharge and bounce back, which I learned to avoid by leaving the CRT's HV connector grounded until reconnect), but your irrational fear of the unknown is just being a big freaking chicken....Unless you have a bad heart condition or the like.

If you get shocked from the yoke somehow (I say somehow cause the only time it happened to me I could not figure out how) with the set on, you will then not worry about small HV jolts.....I've never had my reflexes hard triggered by the HV (sure I'd consciously pull back in a controlled way), but the yoke....without trying everything in my way was smashed out of it including some wires. Yoke voltages and 120VAC are the two things I work with that I'm thoughtfully cautious around.....Now that I have an HV meter I just discharge and stop worrying.

If you are truly dedicated to/focused on working on something (as any experienced auto mechanic will tell you) you will not notice or care as much about small pain. When I was starting out soldering I often would cause my self small burns and not notice until minutes or hours later. I've given my hands small cuts while working on some things and not noticed until long after.

MAN UP!
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Old 10-02-2015, 12:31 PM
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Jon A. Jon A. is offline
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Quote:
Originally Posted by Electronic M View Post
Honestly, if you are wearing rubber soled shoes and not touching any metal that leads back to the chassis you could touch the HV lead with the set off and it would not be much worse than a static shock from shuffling your feet across the carpet and grabbing a door knob.....
Sounds like what happened to me after I aired a bad CRT in a console that had been running shortly before. Back then I had no HV probe. I got a small bite when reaching for a piece of glass dangling from the remains of the evac stem.

Anyway, no pain, no gain.
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Old 10-02-2015, 01:27 PM
MRX37 MRX37 is offline
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Quote:
Originally Posted by Electronic M View Post
You should get an HV probe to use it to discharge the CRT, and confirm HV reg is adjusted properly once you get it going. If you use an HV probe, the CRT second anode should not 'recover' any voltage, and you get to see that it has discharged to a safe voltage. Just clip the ground lead of the probe to the chassis, hold probe by user handle stick the tip on it's far end under the HV suction cup or to the plate at the base of the HV rect tube if more convenient, and watch the needle jump and fade back to zero.
I might pick one up, when I can afford to do so. Right now I can't even afford a thermistor much less an HV probe.

And the rest of your post was unnecessary. You're talking to a guy who recently wrestled with the exhaust system on his truck for 12 hours before the damn parts would line up. I'm no stranger to working on vehicles, or the various injuries resulting from it. Any stripes that I needed to earn, buddy I earned them years ago and there's nothing cowardly about not wanting to risk 15 KV traveling through your body.
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Old 10-02-2015, 03:05 PM
Electronic M's Avatar
Electronic M Electronic M is offline
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Originally Posted by MRX37 View Post
there's nothing cowardly about not wanting to risk 15 KV traveling through your body.
In my book there is, especially given the method your scarred of. The screw driver method was a safe and common technique among service techs for decades....I've even seen SS sets that have warnings not to use that method because the SS HV system was not built to take it. I've done the screw driver bit dozens upon dozens of times before and after I got an HV probe (surprisingly easy to miss-place for a 1' long stick). I've never been shocked doing it, even when the ground clip lead has slipped off the driver mid way through....Hell I've even used wood handled drivers once or twice. Only jolts I've taken are from anode recovery when reassembling (eventually realized that leaving the jug clipped to ground prevents even that), and once or twice forgetting to discharge the HV before removing the suction cup....That don't feel good, but I've gotten bit MUCH worse by 120VAC.

If you work on CRT TVs as a habit you WILL get bit by the HV or MEANER voltages/waveforms eventually, just a matter of time. And it's only spooky until it stops being an unknown experience.....Then it becomes more of a minor nuisance....Like dropping a heavy set on your foot or stubbing your toe (only the pain don't last nearly as long...5sec to 5 min tops), you cuss a bit and move on unphased.
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Last edited by Electronic M; 10-02-2015 at 03:21 PM.
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