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Old March 8th 19, 11:04 PM posted to alt.windows7.general
Bill in Co[_3_]
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Posts: 303
Default Esata - Sata query

J. P. Gilliver (John) wrote:
In message , Bill in Co
writes:
Paul wrote:
Bill in Co wrote:

That is one weird looking connector. It will be interesting to see if


I think the one on my Portégé laptop is the one shown above the one
labelled laptop.

this ever becomes mainstream. I think I'd prefer separate connectors,
but maybe I'm being conservative and old fashioned. I think the eSata


You are not alone, whatever!

ones were a bit (slightly) flimsy at it is, however.

The original ESATA intention was metal to metal contact
and a 5000 cycle rating. The same rating as USB metal connectors.

The internal SATA connector system, is plastic and
the rating is 50 cycles. Although my tests in the
Test machine (swapping drives all the time), is now
many times over that figure. Those connector ratings
are probably a "guaranteed minimum", but I don't know
what "mis-mated" conditions they apply to test that
out.

The usage of metal barrels or surfaces for capture,
makes a big difference to the spec number.

Paul


In retrospect, I misspoke, and was thinking of the SATA connector found
on the internal SATA drive, which I thought was a bit flimsy. The eSATA
connector on the end of the cable I've got looks rugged enough. Sorry!


I remember back in the days of 25-way D connectors and the DIN 41612
family, there were three classes (I can't remember whether class 1 or 3
was best), which were mainly to do with how much gold plating was on the
pins, rather than mechanical type of wear. The cheapest - about 50p for
a D-25 - was "gold flashing", i. e. there was gold there, but really
only to protect the pins from corrosion in storage while they were
waiting to be assembled onto something and used; they were really
intended for things that were plugged in and left in place, and rated at
something like 3 to 5 insertions. Class 2 was IIRR about 0.5 to 1 micron
of gold, and intended for things like circuit cards that would be
replaced or moved around from time to time, and rated for a few tens of
insertions. The most expensive - about 5 pounds for a D-25 - were 5
microns gold, intended for things being reconnected often; I think they
were at a few hundred insertions.

(For D types, there was also whether the pins were "formed" - made out
of thin sheet brass, thus hollow [these worked better than you'd
expect!], or "turned".)

I don't _remember_ anything about the plastic housings having different
number-of-mating-cycles qualities.


It never even occurred to me that the depth of the gold plating was such a
controlled quantity in terms of those classes and the number of "rated
insertions". Or that the lightest coating was only intended to protect
against corrosion while in storage, and only while in storage, and nothing
more. Interesting.


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