[Milsurplus] Re: British Army Radio During WWII

[Don Davis]

I don't want to beat a dead horse - but I will anyhow.

No.  Comm'l parts have nothing to do with MIL-SPEC parts.  By definition,
all MIL-Spec parts are part types that have been previously qualified and
have to pass lot tests (Group B = life testing of samples from each lot,
Group C = burn-in testing for lots, Group D = radiation / other
environmental lot screening) and certain 100% testing (Group A = 100%
screening parameters).  This is why the gov't pays $200 for toilet seats in
aircraft - they're all tested, and built to a certain spec.  Have to meet
certain construction rqmts as well, so parts used in modern mil gear doesn't
look exactly like your Kenwood or Yaesu (some do, some don't).  Plastics,
for example , are usually avoided in MIL-SPEC parts.

There was a move a while back to use COTS (commercial off-the-shelf) parts
in certain non-critical applications.  Problem was the gov't still wanted
the parts to meet MIL-SPEC ultimate performance, but didn't want to pay for
it.  Neither did the vendors.

The closest we have to Comm'l are some of the DESC spec sheets now coming on
line.  Takes a QML vendor's parts & writes a screening spec around it.  Same
as comm'l part, but more $ due to screening.

MIL-SPECS are constantly updated, and most of the parts that we know & love
are long gone.  New construction is nearly 100% surface mount.

73s

Don   AD6PB  - A guy who buys a ton of Hi-Rel parts for a living.

> --- James C Whartenby <antqradio@juno.com> wrote:
> > Greetings William and the group
> >
> > It is interesting to note that commercial components
> > available today meet
> > or exceed mil standards.  I have been out of this
> > field for several years
> > so I am not positive about the revisions to
> > specifications.  But I
> > believe the present component quality is so high
> > that there have not been
> > many revs to the mil specifications for components
> > like resistors,
> > capacitors and inductive components.
> >