On Thu, 16 Oct 2014 02:36:44 -0500, Lostgallifreyan
wrote:

Jeff Liebermann wrote in
:

All too
often, the radio would be fully functional, but the system would be
down because the BITE was complaining about something spurious.
Someone suggested a second BITE to monitor the first.

The devil drives a fine wedge.

I am the devil, or at least some of my friends and customers think I
am. (The difference between a friend and a customer is the customers
pay me, while the friends do not).

What I do in this case is let the thing
pass with a warning to the user. What they make of it is up to them, but it
is ALWAYS best to have the machine surrender control if in doubt, because the
alternative is to ALWAYS leave a person wondering exactly where something
first appeard to go wrong, simple because it did NOT appear. A dumb human can
usually do more than a smart but broken machine.

That would not work for this situation. The end user was the USCG
(United States Coast Guard). Average age of the users is about 17 or
18 years old. Specifications were to not let anyone make a decision
beyond looking for a red light on top of the PCB, and replace whatever
lights up red. I looked back at my troubleshooting abilities (mostly
automotive) when I was their age, and decided that it was the best
philosophy.

Somewhat later, I visited the USCG depot level repair shop on Treasure
Island in the middle of San Francisco Bay. The techs there were
better qualified, but still mystified if replacing a board did not
magically solve a problem. During the tour of the facility, I was
shown the "bone pile", which was a rather large collection of radios
used for spare parts. I did some quick math and estimated that it
contained about 2% of the radios we sold to the USCG.

The BITE boards were not totally wasted. I showed them how to use
them as a troubleshooting and testing aid for bench testing. With
some help, I was able to diagnose about 15 radios and fix 10 of them
using the BITE boards, which demonstrated that they were not a total
wasted. Every test bench soon had a set of BITE boards.

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