Todd, you have to be very careful when removing those 75TH tubes, which were the original types used in the 30K-1.
What you need are adapters that slip over the grid pins. These were made by Eimac to be used with any of these tubes that had that pin arrangement. These caps slipped over the pins and were much more sturdy than the grid pins. All my best. Dave, W3ST Secretary to the Collins Radio Association Publisher of the Collins Journal www.collinsra.com ----- Original Message ----- From: "Todd Bigelow - PS" <[EMAIL PROTECTED]> To: <amradio@mailman.qth.net> Sent: Wednesday, December 31, 2003 12:20 PM Subject: Re: [AMRadio] Need advice on storing RF power tubes > David Knepper wrote: > > >I wished that I had used spell check on my post. > > > >"attempting" and "during" > > > >In my humble opinion, the reason for the filament to shatter, break, snap, > >open, split; crack, divides, etc. or whatever occurs is physical jarring. > > > > I'd agree with this. And as Geoff pointed out, sagging over time if > stored incorrectly could be a problem too. I have an old 250TL still in > its metal shipping frame, hanging upside down but vertically, suspended > by springs. Amazing what they used for packaging back then! > > >However, I had a gentleman in New Zealand ship me two 75TH tubes for my > >30K-1 and they arrived in great shape. Think of how many "frequent-flyer > >miles" these tubes had since leaving the factory in California. > > > > Indeed. I'd be curious Dave, to hear what kind of plate cap arrangement > yours use. I broke one on the mod 5 by trying to take it out of the base > and slip it out where I could get to the cap. Someone came up with a > split-cap design held in place by two of those ring clips requiring > special pliers to remove. Just the slight amount of torque from lifting > the tube out of the socket *slightly* was enough to cause the top seal > the break. Found a pair last spring at a hamfest, after looking for a > couple of years. Also, I thought the 30K-1 used 75TLs, or was that just > 'early design' and production ended up going with the TH? > > ~ Todd KA1KAQ > > _______________________________________________ > AMRadio mailing list > AMRadio@mailman.qth.net > http://mailman.qth.net/mailman/listinfo/amradio
