On May 3, 7:11�am, "Michael J. Coslo" wrote:
On May 3, 7:52 am, K6LHA wrote:

some snippage

A generalized statement like that indicates no experience with adverse
environments. �One can "perform" like a champ at room temperatu
re in a
residence environment but try it below freezing or in a vehicle that
has been in +118 degrees F all day (interior is MUCH hotter).

Since this has become a "can you top this" sub-thread, I'd like to add
that
the WHERE I experienced +118 F temps was at Kern County Airport #7,
Mojave, CA, the same old ex-USMC airfield where Scaled Composites is
located (maker of Space Ship 1). A 1.6 GHz R&D radio was being
flight- tested at the time with me sweating at the ground station as a
reference point for the airborne avionics. It worked and we got
data. It was the first generation of three and had lots of circuitry
that surprised me by keeping on working.
�
I haven't been involved in Mil spec testing. I was involved in Cable
Television testing, in which we cycled between extreme temps - don't
remember the exact temps, so I just used "extreme". We did immersion
tests in salt and fresh water. We did vibration testing. Neat device,
it was a sort of mini-system, we sent signals through it, and tried to
run to failure. Shake and Bake, we called it. After a month or so
without a failure, we'd give up. Some equipment was used by the Navy,
so the testing method must have meant something. note, we tested all
the models this way.

Sounds like the 'orphan' RCA Corp. division of the West coast over in
Burbank, making CATV systems, mainly repeaters for cable TV systems.
RCA bought the facility (and many people) from Collins Radio (their
effort
to expand but to little avail). Cable things had to sit outside 24/7
and endure
all that nature could bestow on it. Sometimes the cable engineers
would
come over to EASD in Van Nuys to use the environmental test equipment
there for bigger arrays.

So while mil-spec testing is great if the equipment needs it, I have
no trouble at all with accepting - and paying for - equipment that is
tested to a level of ruggedness more in line with Amateur needs.

I'll accept that. Anecdote: In 1964 I built a SW BC receiver for my
father so
he could listen to Radio Sweden on their HF BC transmissions and not
disturb me in the workshop. He died in 1975 and I put the homebuilt
on a
top shelf in the workshop then. 'Standard' construction, aluminum
chassis, no
special techniques of its time. Come the January 1994 earthquake in
nearby
Northridge and it vibrated off the 6 1/2 foot shelf to fall on the
concrete slab
floor of the workshop. Fell on one corner and did lots of damage in
bending but the six all-glass tubes all survived to test good. Tuning
capacitor jammed
shut, one IF can broken, two big tears in the speaker. Thin plywood
cabinet
useless to repair. One ceramic tube socket cracked.

Since then I've taken pains to keep small things on high shelves
secured and
bookcases screwed to studding in this wood-frame residence. If small
things are not fastenable, I've made a small "fence" around it to
limit movement. Wood-frame buildings survive better in quakes than
brick structures since they have a natural flexing under vibration.
Another caution was to keep a "fall area" free such as books falling
off cases. That's paid off in two subsequent small
earthquakes, no damage.

73, Len K6LHA