Tube filiment voltage ???

[Magnus Danielson]

From: terry michaels <104065.2340 at compuserve.com>
Subject: Re: Tube filiment voltage ???
Date: Mon, 3 Jan 2000 20:58:00 -0500

> The initial development of the vacuum tube for use as an audio amplifier
> was done by the Bell Telephone company around 1913.  With extensive lab and
> field testing of large numbers of tubes, and a great number of design
> changes, the lifetime of telephone repeater tubes was around 70,000 hours
> by the early '20s. They later developed vacuum tubes for intercontinental
> submarine telephone cables that would operate more than 15 years without
> failure.  The failure modes of these tubes, and the design changes done to
> extend tube lifetime, are detailed in a number of textbook and periodical
> sources.  I can try to put together a sourcelist if anyone is interested in
> researching this further.

Ah. At least I would be interested to read something more on that. The
reliability literature that I have does not cover tubes, so I am kind of
missing that.

BTW. What book should I be sure to pick up for a good reference on tube
parameters?

Cheers,
Magnus