In article ,
"Michael A. Terrell" wrote:

Telamon wrote:

No I have not worked with FQPSK modulation. My work involves digital
signals mostly. I consider the environment to be mixed signal as a best
description. Telecommunications and data communications semiconductors
from low line rate to 10 G/bit is what I work on in the production test
area. All these signals need to transverse circuit boards and various
connectors and cables. Rise and fall times as fast as 18 ps and clocks
up to around 12.5 GHz. It real fun trying to measure rise and fall times
that fast and jitter on the edges and all the data eye measurements that
come into play. I design the circuit boards and specify everything else.


I worked in engineering and on the production floor when the RCB2000
was released to production. Most of the radio was on VME cards but
there were about a dozen other small boards not counting the ones in the
RF sections. About a dozen processor chips including the Aaeon PC-104
embedded controller and the PC-104 IEEE-488-2 interface board.

I know what you mean about measuring signals in that range.
Unfortunatly, some of the other techs were good at RF but couldn't
handle digital so I got stuck with troubleshooting $8,000 mixed signal
circuit boards that no one else could fix. I had to fight with our MEs
to change the paste solder because of flow problems in the oven and to
switch to Ersin solder for rework. Have you ever used .015" solder
while working under a stereo microscope? It takes steady hands.

Yes I have. I can't do it without the microscope. The smallest I have
worked with is 0402 size under 10X. We have parts that are half that
size now but I have not solder them myself.

If I'm planning to do do some soldering work I don't take my morning
coffee.

It's just a physical skill that many engineers don't have so I end up
fixing things for other people.

--
Telamon
Ventura, California