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Old 07-30-2017, 11:25 PM
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old_tv_nut old_tv_nut is offline
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Join Date: Jul 2004
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The charge is held between the inner dag and outer dag acting as capacitor plates and the glass acting as the dielectric. Venting makes no difference, except that the charge might leak off faster due to humidity in the air.

Just discharge the tube properly before you vent it, and there won't be any charge to worry about.

REMEMBER that discharging once is not enough, because the glass dielectric can undergo electrical relaxation and restore part of the charge. To be safe, discharge once, wait 30 minutes or so and discharge again. On the other hand, relaxation is worse if the initial voltage is higher, so a 5 inch tube, which will use lower voltage, and have less total charge, is not going to have anywhere near the secondary charge that a large color CRT would have.

Edit: If the tube has been sitting around unused for months, it probably has no charge anymore, which you can verify when you get no spark on the first discharge.
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