I asked on the Tube Collector Assc list and got this response from Lane Upton, who is a retired engineer from Eimac and one of the knowledgeable people around regarding the manufacturing of transmitting tubes:
"The leakage/breakage of metal to glass seals is primarily due to thermal or mechanical stress. There should be no reason for tubes just lying around to have any seal problems." Lane Upton 73, Mark W1EOF > -----Original Message----- > From: charles free [mailto:[EMAIL PROTECTED] > Sent: Tuesday, January 31, 2006 10:13 AM > To: [email protected] > Subject: [AMRadio] 813 question > > > Hello all, > > I have a buddy who insists that if I don't get my old > 813's out of the "future project" box and fire the > filaments up on them now and then, the base seals will > eventually deteriorate. I guess he is talking about > the adhesive that secures the base to the bulb. I > don't see how the glass envelope where the leads pass > through the glass could be affected by lack of use, > but maybe one of you folks has experience with this. > Anybody heard of this one before? > > W4MEC, Charlie in NC <SNIP> -- Internal Virus Database is out-of-date. Checked by AVG Free Edition. Version: 7.1.375 / Virus Database: 267.14.22/239 - Release Date: 1/24/06
