Re: Square root of a negative rral value

"Glen Herrmannsfeldt" <gah@xxxxxxxxxxxxxxxx> wrote in message news:ggpfmr$nj9$1@xxxxxxxxxxx
Gary Scott wrote:

Its fairly well known in the electronics industry that component failure
is intentionally designed in (designed just good enough but not too
good). I hope they werent in that mode of thinking that early :(

For incandescent light bulbs there is a known trade off between
life and visible light output. Knowing the cost of electricity,
the cost of bulbs, and the cost to change bulbs one can find the
optimal point on the curve. For industrial use, where you pay someone
to replace bulbs that may be in hard to reach places, the optimal
point is a little different than for home use.

For other components the trade off might be less obvious.

That is entirely irrelevant.

Valves used in computers were ordinary domestic ones as well as
special quality ones. The latter had a guaranteed life of 10,000 hours
(to maintain their characteristics), and characteristics were
more consistent between valves. Of course, valves lasted much much
longer than that (10,000 hours), just as they did in domestic radios.

It should also be noted that computers were not turned on and off
repeatedly, but kept running continuously (maybe all week).
Of course, if the computing was completed the computer would be switched off
at the end of the night. They would also be switched off to carry out
component replacement such as resistors or capacitors, or to check
component values, etc.