I would not be too concerned about leakage. It happens, but very very seldom.
I have tubes that are still new in box from way back in WW2 that I have used
and none have ever shown air leakage. Easiest way to determine if they are
still good is to plug them in and fire up the rig.
Ray wa7itz
________________________________
From: Amps <amps-bounces@contesting.com> on behalf of Chris Pedder
<chris.g3vbl@gmail.com>
Sent: Saturday, May 6, 2017 8:11 AM
To: Amps@contesting.com
Subject: [Amps] PL172 (8295)
For the last 37 years my Hallicrafter HT33A has been sitting on the floor
in the garage with an 8295A (Ceramic) fitted. I have a pair of 'new in the
box' PL172s one of whose boxes is still sealed. Packing date was 6/67 so
that's almost 50 years.
I suspect that the glass seals will have leaked but is there anyone with
experience of these tubes after such a long period of time. If I were to
construct a hi-pot device, what sort of values should I expect from a
'good' tube? Thanks.
Chris G3VBL
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
Amps Reflector - Contesting.com Ham Radio Mailing
Lists<http://lists.contesting.com/mailman/listinfo/amps>
lists.contesting.com
Welcome to the Amplifier mailing list! This list is intended for the exchange
of information on HAM RADIO Amplifiers related topics ONLY. Our goal is to keep
...
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|