On 18 May 2014 02:51:57 GMT, "DoN. Nichols"
wrote:

On 2014-05-17, Larry Jaques wrote:
On Fri, 16 May 2014 12:30:55 -0400, "Michael A. Terrell"
wrote:


Tom Gardner wrote:

I had a huge struggle with soldering a couple of DB-9 connectors, my

[ ... ]

BTW, it isn't a DB-9, it is a DE-9. The second letter is the shell
size. The common 25 pin shell is a 'B'. The SVGA monitor plug is a
HDE-15.

http://en.wikipedia.org/wiki/D-subminiature

Interesting! Even when I was buying them for computers/cables I
built, they were always listed as DB-9s.

The people who know what they are doing will recognize them
anyway, knowing that there is no such thing as a DB-9, and the use of
the common wrong name makes those who don't know satisfied that they got
what they asked for.

The letter sequence is weird, BTW. Assuming the two rows of
individual pins, they are "DA-15", "DB-25", "DC-37" "DD-50" (really three
rows) and finally "DE-9".

The 9-pin size was an afterthought, and you can't back up to a
letter before 'A' unlike being able to back up '1' to '0' (or even minus
numbers at need). :-)

I don't know for sure who originated the series, but the first
ones I remember were made by Canon, and had white Nylon insulators,
which happily melted as you were soldering, so if you weren't quick
enough at it, you wind up with the pin at an angle as the Nylon hardens
again. :-)

Enjoy,
DoN.
I used the 50 pin version on one rig in R&D. Over my career, I moved
from massive quantities of H-9 hose (pneumatic instruments) to poly
tubing to direct wired, to 37 pin Amphenol connectors (with the crimp
insert pins) to the 50 pin D connectors. Then finally to networked
connections.

The Amphenol connectors came on my first cart rig, where I could roll
carts with different capabilities in and out to the main line. The D
connectors were much easier to use, because we used them on ribbon
cable. I also had a few failures on the Amphenols due to faulty
insertion or removal techniques. My last rig in that style had about
1000 individual wire terminations in the main cabinet. I'd land the
ribbon cables on a breakout board, cross wire to the computer I/O
boards. Made it easy to add and modify instrumentation.

The networked rigs were a quantum leap forward. I was able to make
location independent carts which could be used (or not) anywhere in
the pilot plant, and no long runs of signal wiring anywhere other than
the coax or optic fiber network.

There was talk of wireless when I retired, but I concluded that was a
bad idea in the chemical industry. Maybe I was just too old
fashioned, but the thought of someone interfering with a potentially
dangerous process with a cell phone or appliance, or intentionally by
some other means made me very nervous.

Pete Keillor