Just encountered something really interesting with the 12LP4. This tube is a rebuilt tube rebuilt by national video corp in Chicago. When I powered the set on in complete darkness I got a extremely dim picture for a second then it disappeared. After taking a closer look at the face of the CRT I could barely see some damage on the phosphor in the center of the CRT face. looks like a bit of the phosphor was sucked off when the tube was relieved of its vacuum when it was rebuilt? Not noticeable in normal light just when I can see the filament from the CRT glowing inside the neck when looking through the screen. Did rebuilders usually cut the neck off with the vacuum still present inside of the tube? I have no other possible explanations for this. 
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Admiral C322C2 Regent (Restoring)
RCA CTC-7 Pensbury (Restored)
RCA CTC-5 Westcott (Restored)
CRA CTC--4 Director 21 (Restoring)
Last edited by SwizzyMan; 09-24-2015 at 07:08 PM.
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