Steve Thompson wrote:
>
>
>-----Original Message-----
>From: Phil Clements <philk5pc@tyler.net>
>To: 2 <2@vc.net>; AMPS <amps@contesting.com>
To: <amps@contesting.com>
>Date: 21 August 2001 05:12
>Subject: Re: [AMPS] RJ-iAvacuum relay
>
>
>>
>>A long-time Jennings employee once told me that
>>when Friday afternoon came around at the plant, and
>>production was lagging seriously behind due to quality
>>control rejects, one would hear the phrase "glip it and
>>ship it" coming from upstairs. A little dab of glyptol was
>>placed on the area of concern, and out the door.
>
>I have a large glass bodied vacuum relay that developed a crack by one of
>the pins. The internal plating corroded and breakdown dropped to 6kV. I've
>sealed the crack with a varnish similar to glyptol. There's what appears to
>be a getter in there - will it have enough capacity to 'repair' the vacuum?.
>Does it need activating somehow?
>
Sealing the crack will prevent any further "breathing-in" of moisture,
but the getter will have been the first thing to react with the air
leaking in.
Also, a getter is not designed to have enough capacity to pump the whole
volume down from atmosphere - it is only for final clean-up of the
vacuum, so reactivating it (even if you could do it without cracking the
seals even more) won't help.
BTW, I did a calculation recently showing that a typical "vacuum" tube
(pumped to 10^-8 mm Hg) still contains around 1000,000,000 free gas
atoms!
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
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