Pinouts

Over the years, I have collected many pinouts for all sorts of interfaces, connectors, jacks, etc.  These are all stored on my laptop and in my smartphone.  It is easy enough to look these things up online, however, there are occasions when the internet is not available for whatever reason.  Thus, this is my collection of pinouts, many of which have been adapted from wikipedia articles.  Many times I put things here for my own use.  However, if I have spent ten minutes looking for the USB pin out on my smart phone, someone else has done the same thing.  Most all of these images have higher resolutions available.

Enjoy!

EIA/TIA 568a and b ethernet cable standard
EIA/TIA 568a and b ethernet cable standard

Standard networking connectors for Ethernet connections. Rumor has it that only the “A” standard is accepted for government work and the “B” standard is being depreciated.

803.3af Power over Ethernet, imposed on EIA/TIA 568 a and b
803.3af Power over Ethernet, imposed on EIA/TIA 568 a and b

Power over Ethernet pinouts. More and more commonly used in VOIP phone systems, but can also be found in wireless access points and other things of that nature.

10/100 base T cross over cable
10/100 base T cross over cable

Ethernet crossover cables are useful for connecting to similar pieces of equipment together, e.g. a computer to a computer, or a switch to a switch. Many new switches have port sensing, which will automatically cross the connection if a straight through cable is used.  Others have a specific port or a switch for a specific port which will cross over the cable.  Gigabit Ethernet uses all four pairs, thus a 1000 base T crossover looks a little bit different.

10/100/1000 base T Ethernet crossover cable
10/100/1000 base T Ethernet crossover cable

This type cable is backwards compatible with 10/100 base T systems.

Registered Jack 11/14/25
Registered Jack 11/14/25

Telephone system equipment jacks.

Registered Jack (RJ) 48, commonly used on T-1 and ISDN circuits
Registered Jack (RJ) 48, commonly used on T-1 and ISDN circuits

RJ48 and 48X used on T-1 (DS-1) and ISDN connections.  Since BRI and PRI ISDN are two wire circuits, the active pins are 4/5, which is the same as an RJ11.  I have often used RJ11 jacks for ISDN and found no issues with doing so.

T-1 (DS-1, DSX-1) crossover cable
T-1 (DS-1, DSX-1) crossover cable

Crossover cable for T-1 (DS-1 or DSX-1 interface). Note, this is different from an Ethernet crossover cable, which will not work for in a DS-1 interface.  A T-1 loopback connector goes from pin 1 to pin 4 and pin 2 to pin 5 on a 8P8C connector.

RJ21 and 21X color code.
RJ21 and 21X color code.

RJ21 and 21X connectors are often found on the side of punch blocks and make for quick connections on cabling trunks.

25 pair color code
25 pair color code

The generic 25 pair color code, which is always a good thing to have.

RS-232 data pins out for various connectors
RS-232 data pins out for various connectors

RS-232 is still commonly used for data transfer in broadcast facilities. RS-485 is also used, however, that standard is often used with screw terminals or some other generic connection.

Null modems, cables and pinouts
Null modems, cables and pinouts

Null modems for connecting equipment together and testing.

Universal Serial Buss (USB) connections and pinouts
Universal Serial Buss (USB) connections and pinouts

Various USB connectors and pinouts. USB has replaced RS-232 data ports on most newer computers.

VGA connector and pinout
VGA connector and pinout

Computer graphics card pinouts.

Computer Parallel port pinout
Computer Parallel port pinout

Computer parallel port pinout, not used very much anymore, replace by mostly USB devices. Can also be used as a limited GPI/GPO interface.  Some small automation software programs use pins 10,11,12,13 and 15 for closure information and pins 1, 14, 16, and 17 for output switching, machine starts and the like.

PS2 mouse and keyboard connector
PS2 mouse and keyboard connector

PS2 mouse and keyboard connectors, again, replaced by USB but still found on older motherboards.

RJ-45 to balanced analog and digital audio
RJ-45 to balanced analog and digital audio

RJ-45 to balanced audio. This is a fairly standardized audio application for RJ-45 connectors developed by Radio Systems/Studio Hub. It is also used by Telos/Axia and Wheatstone, although often the +/- 15 VDC power is not included.

XLR connectors, old technology, still used
XLR connectors, old technology, still used

The ubiquitous XLR connector, still used for analog audio and also AES/EBU digital audio.

The Telos NX-12 Talkshow phone system

I have worked with my Telos telephone interfaces in various studios. They are well designed and intuitively designed pieces of equipment. The Telos NX-12 is no different.  The first thing different about this telephone system is the web interface.  I have commented before on this; eventually all broadcast equipment will have some type of http interface.  For configuration and monitoring, it makes life much simpler.

Telos’ NX-12 web interface allows the users to define phone lines, call directors and studios:

Telos NX-12 http interface
Telos NX-12 http interface

The NX-12 itself is just a box residing in the rack room.  This is where all of the pots lines or the PRI-ISDN line is installed, firewire, network interface, etc.

The studio end is the call director, which is connected to the NX-12 by a cat 5 cable.  There can be up to four call directors per NX-12.

The nice thing about the NX-12 is that the hybrid can be split into completely separate units, thus one NX-12 can be used for two separate stations, each with up to six lines.  Splitting the hybrid thus requires the use of Firewire or the unit must have an AES card.

This particular unit was installed at WFAS-AM/FM in White Plains, NY.

The Problem with the Phone Company

It they don’t care all that much about traditional phone service anymore.  Through attrition, they have reduced their tech work force to about half what it was 15 years ago.  All of the infrastructure; over head cables, buried cables, office frames, switching equipment, is getting old.  Some of the cabling around here, both buried and overhead,  is the original stuff, installed 100 years ago.  Because it is expensive to replace, they don’t want to change it out, opting to simply limp along, swapping out pairs when a line or circuit goes dead.

I will be surprised if the traditional wired telephone network still exists in ten years.  Think about it, ten years ago were were just heaving a collective sign of relief that Y2K turned out to be nothing, remember that?

For the local phone giant, offering 3 in one (telephone service, internet service and cable TV) is more appealing than servicing their existing accounts, including HICAP (high capacity) data circuits like T-1, BRI&PRI ISDN, etc.  Much less so for a POTS line, which, good luck if you really need it fixed right away, we’ll be over when we get to it, just keep your paints on mister.

I’ve written about this before. A particular station for my former employer uses a T-1 circuit to relay the program from the studio to the transmitter site.  This is fairly common in larger metropolitan areas where 950 Mhz STL frequencies are not available, nor is line of site between the studio and transmitter site obtainable.

Back in 2002, when the company was in the process of aquiring said station, I recommended a 950 Mhz STL.  There was an existing STL license, fully coordinated, that came with the main station license.  Only the equipment was needed.  No, I was told by the CFO, we will do a T-1, thank you very much.  I argued my point, saying that putting our radio station exclusively in the hands of the phone company was a bad idea.  We would have problems with outages and service.  No, said the CFO, this is New York, all the radio stations do that.  Not exactly, New York is about 15 miles SOUTH of here, this is Westchester, the cables are old, a lot of them are overhead, which exposes them to lightning, vehicle damage, water, etc.  There will be service issues if we rely solely on a T-1.

No, he said, “We are using a T-1 and that is final.”  I hate to say I told you so, but… Let us examine the history between then and now:

Date of outage Date of restoration Total days
April 5, 2004 April 9, 2004 4
September 8, 2006 September 10, 2006 2
May 2, 2007 May 5, 2007 3
August 27, 2009 September 4, 2009 10
September 5, 2010 September 15, 2010 10

Fortunately, I wrote all this down in the transmitter site log.  I was able to check it yesterday, when I went to restore the station to normal operation after the latest T-1 failure.

During those periods, we have used BRI-ISDN, which is okay but it was carried the same phone cable.  It is likely to go down if there is a major cable interruption.  We have installed a second T-1 circuit, which fails when the other T-1 circuit fails.  We have used 3G wireless sprint card and streamed audio from the internet.  That didn’t sound great, but we did clear inventory.  We have moved one of the AudioVault servers to the transmitter site, and updated it once a day via shoe leather network, that sounded great, but it was difficult to do.  We have borrowed an ethernet connection from another tower site tenant onsite and streamed internet audio via wired connection, which sounds pretty good.

Still, the best thing to do would be to establish our own STL path to the transmitter and get rid of the T-1 lines.

The Problem with the Phone Company is they are not all that interested in simple copper circuits anymore.  Now, there is something called FiOS, which, it would appear is a much better profit center than ordinary copper circuits.