Re: CRT static charge


Dave Peterson
 

OMG, that's so funny. I totally forgot about that. As soon as my eyes landed on that bit about old TVs my brain jumped back to 1970 and the crackle that accompanied twisting the power/volume knob on the TV flooded back into my mind. Thanks for that old memory! Oh yeah! CRTs! It's been a long while. Perhaps that's part of the nostalgia and joy of old oscilloscopes.
Dave

On Monday, December 7, 2020, 10:44:27 AM PST, Eric <ericsp@gmail.com> wrote:

IMHO that is very normal and a product of the accelerating voltage in the CRT. If it was arcing out of the tube there would be no vacuum left in the tube and  the tube would be bad. All my 7000 series scopes do it and the old tube TV’s used to do it. I used to check the high voltage section of a tv by just running the back of my hand over the the tube about and inch off the face, no dissemble needed. If the hairs on my arm stood up the HV section of the TV was good.

Eric
-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of Dave Peterson via groups.io
Sent: Monday, December 7, 2020 1:36 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] CRT static charge

Thanks Raymond. I figured when dealing with voltages with a "k" suffix it's probably wise to be safer than sorry-er.

Dave
    On Monday, December 7, 2020, 10:32:23 AM PST, Raymond Domp Frank <hewpatek@gmail.com> wrote:

On Mon, Dec  7, 2020 at 07:29 PM, Dave Peterson wrote:


Is this normal?

Could it be an indication of anything untoward?
Short answer to your two questions: Yes, it is, and No, it isn't.

Raymond

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