OT: PC Motherboard with a vacuum tube

From: William Donzelli <aw288_at_osfn.org>
Date: Sat Sep 7 23:05:01 2002

> That reminds me of when I purchased my Tektronix 531 'scope a few
> years ago, back around 1982. The seller had just "repaired" it, and
> somehow had the fillaments connected to the B+ supply. One can
> imagine what things looked like when the scope's B+ relay clicked on;
> all of the tubes were glowing white for a very brief period of
> time---the 'scope was shut off rather quickly. I only had to replace
> one or two tubes, from what I recall.

One thing is certain, however - you severly damaged every one of those
tubes. Whacking the filaments with a huge pulse, even for a very short
amount of time, will almost always reduce the emmission of tubes
(exceptions being tubes with pure tungsten filaments). If you want, take
some junk tubes and zap them on a tube tester - you will see a marked
decrease in the emmission.

> Let's see a PC motherboard,
> with all of those microscopic components, survive something like that,
> and be repaired in a very short period of time! That won't happen;
> hence, one could say that older, and well evolved, technology is
> superior to newer technology in terms of long-term durability and
> repairability.

Tubes more reliable than transistors/ICs? Wow, that is alternative...

William Donzelli
aw288_at_osfn.org
Received on Sat Sep 07 2002 - 23:05:01 BST