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Connectors: A History of Their Technology?
dpbsmith asks: "It seems like a simple engineering problem--construct a device for easily and safely connecting several dozen wires at the same time--but the variety and creativity in their design over the years has been amazing, and, clearly there have been trends, fashions, and styles. In the fifties and sixties, virtually all connectors were roughly similar to the D-Sub design used for RS-232. A stiff, straight pin engaged a springy socket that contacted and bore against it on all sides. There were minor variations in shape and placement; the Amphenol Blue Ribbons (think Centronics), the connectors into which circuit boards engaged, but they were all variations on a theme. I was absolutely astounded the first time I saw a modular RJ-11 connector. Cheap, effective, and utterly unlike anything I'd ever seen before. Who invented these? Western Electric? Recently, we have the USB connector and the Firewire connector, obviously members of the same family (and a cheap-and-cheesy-seeming family it seems); on the other hand, my telephone and my digital camera have connectors that are very small and snap in with a positive lock that must be released with a squeeze, obviously yet another fundamentally different design. What do people know about the design, history, and engineering behind connectors over the years? Is it all hidden away, trade secrets of the connector companies, or is their a story that can be told?"
Sorry -- According to the one source no one seemed to bother with (Amphenol themselves) it is, as the coward pointed out, 'Bayonet Neill Concelman' and was named for Carl Concelman (and not Carl & Concelman).
This was an easy find:
http://www.amphenolrf.com/products/bnc.asp
- I am made of meat.
The UK AC plugs may be large, but they are safe, which is a lot more than I can say for the horrible US AC plug design. I visited the UK last year with a bunch of US multi-voltage video equipment. My British hosts were stunned at how bad the US plug design was, and how easy it would be to shock yourself as you inserted or removed one. The hot blade is exposed with AC power on it - if your finger should slip, you get zapped.
The UK plug design is plastic along the length of the blade, and only the end is metal. By the time you see the metal tip of the blades, the circuit is already broken.
"How perfectly Goddamn delightful it all is, to be sure" Charles Crumb
The USB mechanical spec calls out that the USB logo be molded on one side of the cable in such a way that you can feel it and the other side be smooth. The logo is specified to go up.
:-(
And all was good.
Until manufacturers could save $0.02 by putting their jacks on upside down or sideways. Now you have a bunch of nicely polarized cables that you can orient blindly in the mess of cables, but have no idea which way the jack is oriented.
(Yes, I have an upside down computer from a vendor that knows better and screwed me for $0.02.)
The crufty among us will remember the ultimate minimalist connector. The original ethernet (thick wire) used a large coax cable as the backbone. You connected to it by drilling a tiny hole and inserting your tap into the cable in such a way that it made contact to the core and shield without shorting anything and wiping out the whole network.
:-)
It really made 50ohm BNC look good when it came out.
And I'll take the RF and audio side. :)
1/8" stereo audio - Cute, impossible to insert incorrectly, noisy (electrically), easily broken.
1/4" audio - Big and ugly, until you get used to it. Then you get 18 hours on a modular synth and learn to love them.
RCA - What, like 100 years old or something? Classic, and easy to use.
XLR - Good idea, bulky, but positive contact, locking, and keyed. Pro shops use this for a reason.
UHF (PL-259 / SO-239) - Ancient, gives an impedance spike on the line, fucking impossible to solder with anything less than a 150 watt iron.
BNC - Beautiful. Love this one. I'm converting all RF gear in my shop to BNC, bit by bit. Power handling isn't quite up there, but you can go N for that.
N - Tough, reliable, smooth (impedance-wise), and dead simple to install once you get the hang of it.
F - KILL THIS FUCKING CONNECTOR. Yes, I know it costs you $0.03 per unit, but it's annoying and the inherent 'center conductor IS the pin' is remarkably irresponsible. I'd feel so much better if that cable TV jack on the wall was a BNC.
Hey Taco! Looks like you're using the "infinite monkeys and typewriters" scheme to generate Ask Slashdots again...
Open it up, and solder in some normal connectors...
The reason why 802.11b equip. has these funny connectors is becuase the FCC mandates that wireless equipment have "difficult to obtain" connectors.
If you don't want to solder, then go to http://www.fab-corp.com/ and see if they have what you want.
I did sound on a touring edition of a broadway show back in the early 1980s. The system supplier was Masque Sound, who did most of the shows on Broadway. The bad habits of the stagehands forced the companies to do things a bit differently -
Every single XLR cable was female - on both ends. Every XLR panel connector was male.
The reason was that the stagehands insisted on pulling cables out by the cord. Apparently, pressing the little tab was too much work. Masque found that the female XLR would be the one to break, so they used females only on cables, because they were easier to repair. They would go through and replace every female XLR on every a 32 channel mixing board.
Even more bizzarely, they used 2 prong polarized AC cords for speaker connectors. The speaker cabinets had duplex outlets on the back.
"How perfectly Goddamn delightful it all is, to be sure" Charles Crumb
Making mouse and keyboard identical was stupid.
No, what was stupid was not just running all wires to both connectors. The only difference between the two is that the keyboard clock and data are run to two pins on the keyboard (and not connected on the mouse) connector, and the same thing for the mouse. Just run all the traces to both and you can plug either in to either port.
So, here is what I know. Not everyone here knows their cables or connectors nor do they need to. Here are some simple things to help you out with.
RJ stands for Regents Jack. RJ11 is your typical 2-6 pair telephone jack. RJ45 is your typical 4-5 pair Ethernet pin jack, also gets used for DS1s.
BNC is a Barrel Node Connector. BNC gets used on test equipment, older coax cable NICs for thin or thicknet. Also DS3 twinax cable interfaces. That screw in on the back of your TV set? F-type.
Tons of pretty pictures;
http://www.cmsa.wmin.ac.uk/~alan/compo
Molex appears to have a nice connector tutorial for you to check out. I need to look this over myself;
http://www.molex.com/training/bce/gstoc.
Get yourself a Molex catalog. Every type of cable connector you can imagine. Go to their products page and browse around.
http://www.molex.com
Do not forget Amp, even though their web presence sucks (or last time I looked)
http://www.ampnetconnect.com/
Random cable interfaces, with some pictures;
http://www.peakaudio.com/CobraNet/Netw
Cable Types for 3Com Products
http://support.3com.com/infodeli/tools/
Unix Serial Port Resources: Sun Serial Port & Cables Pinouts
http://www.stokely.com/unix.serial.port.
IEC has standards, like that power plug on the back of your computer -- an IEC 320 plug.
http://www.iec.org/
Your typical U.S. three prong power plug is an NEMA-5-15P (P for plug), and the receptical is a NEMA-5-15R. Here are some charts with pretty pictures;
http://www.leviton.com/sections/techsu
http://www.quail.com/locator/nema.htm
SCSI connectors, pinouts, and protocols, and some IDE/ATA stuff too;
http://t10.org/
Do not forget about the Fiber Channel and HIPPI;
http://www.t11.org
PCI card interfaces;
http://www.pcisig.com/
EIA/TIA;
http://www.tiaonline.org/
Whoa, I just found this... standards for wiretapping?;
http://www.tiaonline.org/standards
Cisco, always a great place to look and learn. Common LAN interfaces from what I see;
http://www.cisco.com/univercd/cc/td/doc/pro
More Cisco, including V.35 and X.21 pictures;
http://www.cisco.com/univercd/cc/td/do
Arg, I had to repost this because Slashdot says, "Your comment has too few characters per line (currently 26.9)." That sucked and needs to change.
If you have more references, please let the world know. I know stuff, you know stuff. Put your stuff here.