I have about ten 813 tubes, mostly hamfest specials, actually, they are ALL ham fest specials.
When I built the 813 rig, I picked 2 and plugged them in, been using those same tubes for 15 years. At one point, I went through my collection, plugging in one tube at a time, and they all worked well. I think there are 2 different kinds, ones with graphite plates, and a few with metal plates? Over all the years of using tubes, I had one 75th loose its filament, and one 4d32 has a piece of metal floating around in it (but it works), and I have an 811 with no plate cap. The 75th was the only one that ever failed, although I have got some bad tubes at fests (4-400, 4cx250b). The Russian 811 tubes all have loose bases and I don't use them. Brett > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of ronnie.hull > Sent: Tuesday, January 31, 2006 1:17 PM > To: Discussion of AM Radio > Subject: Re: [AMRadio] 813 question > > > I have certainly never heard of that, but I'm no expert. > However, I have a box > full of 813's that are ww2 vintage and NONE of them have loose bases. > > R > > > ---------- Original Message ----------- > From: charles free <[EMAIL PROTECTED]> > To: [email protected] > Sent: Tue, 31 Jan 2006 07:12:56 -0800 (PST) > 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 > > > > __________________________________________________ > > Do You Yahoo!? > > Tired of spam? Yahoo! Mail has the best spam protection around > > http://mail.yahoo.com > > ______________________________________________________________ > > AMRadio mailing list > > Home: http://mailman.qth.net/mailman/listinfo/amradio > > Help: http://mailman.qth.net/mmfaq.html > > Post: mailto:[email protected] > > AMfone Website: http://www.amfone.net > > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb > ------- End of Original Message ------- > > ______________________________________________________________ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:[email protected] > AMfone Website: http://www.amfone.net > AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb >
