[Milsurplus] How Much Vacuum in "Vacuum Tubes?"

[D C *Mac* Macdonald]

I'd imagine it was cost effective to rebuild TV CRTs in
those days.  All that would basically need to be done
would be to remove the old electron gun portion,
replace it with a new one with good emission, and
evacuate the glass envelope!

Mac - K2GKK/5




----Original Message Follows----
From: "Jim Klotz" <jklotz77 at verizon.net>
To: <milsurplus at mailman.qth.net>
Subject: Re: [Milsurplus] How Much Vacuum in "Vacuum Tubes?"
Date: Wed, 28 Mar 2007 18:01:36 -0700

Jim, all

My dad used to work in the Sylvania Electric Products warehouse in Seattle. 
When I was a teenager (early 1960's) I worked with my dad in the summers. 
Two of the interesting things I did there were: 1. To let air into returned 
TV picture tubes in preparation for shipping.  There was a special wrench 
used the break off the center locating pin of the tube plug which revealed 
the glass seal.  Tapping the seal cracked it and you could hear the air go 
in.  Those tubes were shipped off to be refurbished but I don't know where. 
It was also interesting to me that the picture tube boxes had a "heavy 
corner which was always turned into the middle of a stack of boxes on a 
pallet.  made the stacks quite stable.  And 2. paste various other brand 
labels on Sylvania picture tubes and their boxes.  I remember specifically 
putting Sears and Zenith labels on.  I don't know if this is true, but I was 
told at the time that each CRT manufacturing company made certain types of 
tubes and these were rebranded for other companies when they used a tube of 
a type they didn't make in one of their products.

Cheers,
- Jim Klotz