ORIGINAL MESSAGE:
At 07:08 AM 1/28/2006, John E. Cleeve wrote:
>Bill,
>I suggest you download from the CQ archives, and read the Bill Orr
>article, for it states, that the tube pin sleeves, are soldered with
>60/40 solder, during manufacture, to ensure the stability of the glass
>envelope to tungsten lead out wire seal. The melting point of the
>60/40 solder is close to, but below that, which would damage the
>stability of the glass/wire seal, if you use a higher melting point
>silver solder, you may destroy the integrity of the seal, and ruin an
>otherwise reclaimable tube.....regards, John. G3JVC.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
That's very interesting. So the 60/40 solder is used as a sort of
thermal fuse to protect the glass/wire seal? Time to change to
ceramic tubes, pronto.
In fact, the GS-35b I ordered arrived today and I got my first look
at one. No pins at all and doesn't even need a socket, just a hole in
the chassis. Way to go Svetlana! :-)
73, Bill W6WRT
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|