wrote in message
...
On Tue, 5 May 2009 16:39:41 -0400, "Eisboch"
wrote:

In the old days, real "skill" meant determining *what* component or
components needed to be replaced using a schematic, meter and/or an
o'scope.

Much of today's modern electronic circuitry has built in diagnostics that
scream "replace me" when they go bad.


We called it "the bad part falls out smoking on the floor".
I liked working on computers when a CPU was the size of a commercial
sub-zero fridge and had 1000 cards. Since then it is "cut open the box
and plug in a new one".



I've been out of the electronics field for over 30 years, but am absolutely
amazed at the advances made since I went to school. I learned vacuum tube
theory, transistors and had a basic introduction to digital in the form of
TTL (5v) logic devices, soon after replaced by 12v CMOS mainly because TTL
just wasn't reliable. A digital display was a row of Nixie Tubes with the
proper internal elements illuminated for a display. Electronics then was
all discrete components and a piece of gear designed with them mounted on a
single layer PC board was "High Tech".

Now, a complete FM receiver and 5.1 surround sound decoder is on a single
chip that costs about 53 cents to manufacture. It's really an amazing
evolution. Soon, PC boards will lose their copper conductors, replaced by
modulated LEDs and fiber optics. The size of products will continue to
shrink and become even more powerful.

Eisboch