On Fri, 15 Apr 2011 08:09:56 -0700, "William Sommerwerck"
wrote:

Extra credit: Calculate the cost of handling a zero cost repair.
That's a repair job that requires zero time and materials to fix, but
still requires, handling, paperwork, overhead, and possibly shipping.
The last time I did that, based on 200 working daze per year and an 8
hr day, I needed to charge about $100 for a zero cost fix.

We are caught in a dilemma... If stuff is made to a high quality standard,
then it won't break down very often, and won't need the repair. But -- to
some degree -- we need stuff to break down to encourage people to buy new
technology, which appears at an ever-faster rate.

The company motto is: "If this stuff worked, you wouldn't need me".
It's on all my stationary and business cards. Nobody has disagreed in
the last 30 years.

Designed obsolescence is one of the unpleasant side effects of CAD
(computah aided design). When it is possible to model the lifetime of
a product on a computah, one can easily design a product for a
specific life. For example, electrolytic capacitors can be selected
for a target lifetime based on temperature, ripple current, and
voltage rating. The life of power semiconductors can be estimated by
dissipation, temperatures, and the number of power (thermal) cycles.
If I offer a 1 year warranty, I would probably design for a 2-3 year
life. For a 5 year warranty, I would use better parts and run at
lower temperatures. Sometimes, I wonder if the bad-caps problem is
the result of manufacturers realizing that having products blow up
after some predictable time isn't a bad idea, and intentionally using
junk caps. (Everything is a conspiracy).


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558