I remember those little rolls well, as well as working on those old Tek room-heaters. The CRT's had the most wonderfully sharp traces, though - especially the 547 :)
Steve, W1ES/4 -----Original Message----- >From: Garey Barrell <[email protected]> >Sent: Jan 2, 2012 10:26 PM >To: Don Cunningham <[email protected]> >Cc: richard radke <[email protected]>, [email protected] >Subject: Re: [Drakelist] L4B Oddity > >Don - > >There seems to be a lot of confusion over 'silver solder' and 'silver-bearing >solder'. > >Silver solder melts at around 1300 degree F, and is typically applied with a >small torch. It's >primarily used for jewelry and other tasks needing a 'hard' solder. I doubt >if the glass metal >seals around the filament pins of the 3-500Z would withstand that heat without >fracturing. I could >be wrong... > >Silver-bearing solder melts at around 700 degrees F, and is applied using our >more familiar >soldering irons. This solder is used for soldering parts that have >metalization 'flashed' onto >ceramic or other insulator, such as SMD parts and the famous Tektronix ceramic >tie strips used in >their scopes. Plain Lead/Tin 63/37% solder will 'leach' the silver out of the >flashed metalization, >loosening and finally breaking the bond. This is why Tek included small rolls >of silver-bearing >solder inside their products. > >73, Garey - K4OAH >Glen Allen, VA > >Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line >and TR-4/C Service Supplement CDs ><www.k4oah.com> > >Don Cunningham wrote: >> On the first question, I have heard of the solder melting out of the pins on >> the filaments of both >> the 3-500Z and the 3-400's. If that has happened to your tube, you might be >> able to just >> re-solder it and be okay. Some have said to silver solder it, but it seems >> to me that silver >> solder requires an awful lot of heat and I would be careful doing that. >> >> Second question: I wouldn't think that was a good idea, but then I'm no >> expert, so hope Evan is >> out there, hi. >> 73, >> Don, WB5HAK >> >> > >_______________________________________________ >Drakelist mailing list >[email protected] >http://mailman.zerobeat.net/mailman/listinfo/drakelist _______________________________________________ Drakelist mailing list [email protected] http://mailman.zerobeat.net/mailman/listinfo/drakelist
