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The Answer to Ailing Copper

I don’t know how things are in your neck of the woods, but here in the Northeastern US, our old copper TELCO networks are on their way out.  This is a problem for broadcasters who still rely on POTS lines (Plain Old Telephone Service) for transmitter remote controls, studio hot lines, etc.  The vast majority of my transmitter site access is through dial up remote controls.  There are a few locations that have web based remote controls, but to be honest; the phone part of my smart phone still gets a lot of use.  There are several locations where the old copper is just failing outright and not through a lack of effort by the repair techs.  Generally, the copper pairs get wet and develop a loud hum, which makes the remote control unit either hang up or become unresponsive to touch tone commands.

The best course of action is to get some type of VOIP line installed.  Here is the rub; many transmitter sites are nowhere near a cable system.  Several times, I have contacted the cable company to see if they will provide a VOIP phone line at a certain site.  The response is usually; sure, we can do that!  However, it will cost  you (insert some ridiculous amount of money) to extend the cable to your transmitter site.

LAN extensions to the transmitter site are a useful for a number of reasons.  More and more transmitters are equipped with web interfaces as are processors, UPSs, transmitter remote controls, security cameras,  etc.  LAN extensions can also be used for backup audio in case of STL failure.  Finally,  an inexpensive ATA (Analog Telephone Adaptor) and DID line can replace a POTS line for a lot less money.  One example; voip.ms has the following plans as of this writing:

Plan type Per month per DID number (USD) Incoming call rate (USD) per minute Outgoing call rate (USD) per minute
Per minute $0.85 $0.01 (USA) $0.009
Unlimited $4.25 $0.00 $0.009
Toll Free (800) $0.99 $0.019 $0.009

Any of those plans surely beats the standard TELCO rate of $40-50 per month per line.

Design criteria for a wireless LAN system needs to take into account bandwidth, latency and reliability.  Each VOIP phone call takes anywhere from 28-87 Kbps depending on the protocol being used.  If the wireless LAN is being used for other things such as back up STL service, access to various GUI’s, etc then the total bandwidth of all those services need to be considered as well.  Do not forget ethernet broadcast traffic such as DHCP requests, ARP, SMB, etc which can also take up a fair amount of bandwidth.

For LAN extensions, I have been using a variety of equipment.  The older Moseley 900 MHz LAN links still work, but are slow in general.  The Ubiquiti gear has proven to be both inexpensive yet reliable, a rarity to be sure.  There are several links to various transmitter sites running on various types of Ubiquiti gear, usually without problem.  One simply needs to remember to log into the web interface once in a while and make sure that both ends have all the firmware updates installed.  They are cheap enough that a couple of spares can be kept on the shelf.

The following diagram shows how I replaced all of the copper pots lines at various transmitter sites with VOIP:

Diagram of LAN extensions to various transmitter sites

Diagram of LAN extensions to various transmitter sites

List of equipment:

Nomenclature Amount Use New or used
Ubiquiti Rocket M5 3 AP and station units New
Ubiquiti AirMax 5G-2090 90 degree sector antenna 1 AP point to multi-point antenna New
Ubiquiti Rocket Dish 5G-30 2 Station antennas New
Ubiquiti ETH-SP-G2 3 Lightning protection New
Trastector ALPU PTP INJ 6 Lightning protection out door units New
Cambium PTP-250 2 Point to Point link Existing/Used
Motorola Canopy 900DA PCDD 1 AP point to multi point Existing/Used
Motorola Canopy 900DA PCDD 2 Station Existing/Used
Microwave Filter #18486 diplexer 3 Diplexer 900 MHz ISM band and 944-952 STL band Existing/Used
Cisco SPA122 ATA 9 Dial tone for remote controls New

The main studio location has the gateway to the outside world. This system is on a separate subnet from the automation and office networks. From that location a point-to-multipoint system connects to the three closest transmitter sites.  This setup uses the Ubiquiti Rocket M5’s with various antenna configurations.  Then, from one FM transmitter site, there is an existing 5.8 GHz path to another set of transmitter sites.  This uses Cambium PTP-250s.

The next hop rides on the STL system, using Motorola Canopy 900 MHz radios and Microwave Filter Company #18486 dilpexers.  These are long paths and the 900 MHz systems work well enough for this purpose.  The main cost savings comes from reusing the existing STL system antennas which negates the cost of tower crews to put up new antennas and or rent on the tower for another antenna.

There is a smaller sub system many miles away that is connected to the outside world through the cable company at the AM transmitter site.  Unfortunately, due to the distances between the main studio and those three stations, there was no line of site shots to these sites available on any frequency.

When installing the 5.8 GHz systems, I made sure to use the UV rated, shielded cable, shielded RJ-45 connectors and Lightning Protection Units (LPUs).  Short cuts taken when installing this equipment eventually come back in the form of downed links and radio heads destroyed by lightning.

Regardless, I was able to eliminate seven POTS phone lines plus extended dial tone service to two sites that previously did not have it before.  In addition to that, all of the transmitter sites now have Internet access, which can be useful for other reasons.  All in all, the cost savings is about $310.00 per month or $3,720.00 per year.

Bucket Trucks and Landing Craft

Hopefully that title is descriptive enough:

ATT bucket trucks, , mobilized via landing craft to Pleasure Beach

ATT bucket trucks, , mobilized via landing craft to Pleasure Beach

We loaded a couple of ATT bucket trucks on a landing craft and waged an assault on Pleasure Beach.  This is to finalize the repair work from Hurricane Sandy last year.  The other factor is the construction taking place on the Island.  The City of Bridgeport is constructing a park, which involves extensive repairs and renovations to the buildings.  Construction vehicles driving under the old lines have ripped them down several times, thus repairing the lines on the new utility poles was necessary.

ATT truck offloading

ATT truck offloading

ATT truck offloading

ATT truck offloading

ATT is the LEC for the Bridgeport area, something they don’t do in most other parts of the country, from what I am told.

Landing Craft Challenger

Landing Craft Challenger

It took approximately four hours to complete this work and reload the trucks back on the landing craft.  The boat itself looks like a slightly modified LCM (Landing Craft, Mechanized), which were produced from 1943 onward.  This is an LCM-8.

WICC towers

WICC towers

WICC towers almost in line, I was about one second too late with this shot. This would be “down the bore” of the daytime pattern into downtown Bridgeport.

WICC towers

WICC towers

Another shot of the WICC towers. These were designed to hold up a horizontal T top wire antenna strung between the two of them.  At some point in the early thirties, somebody realized that the tower itself could be excited as a vertical radiator and the antenna configuration was changed. Up until the mid 1970’s there was a horizontal wire which supported third wire element hanging between the two towers, making it a three tower directional array.  This was removed and it was then that the current phasor and two tower DA-2 system was installed.

All in a day’s work.

Goodbye, ISDN

The imminent demise of ISDN has been talked about for some time.  There now appears to be a date attached which makes it semi-sort of official.  As of May 18, 2013, Verizon will no longer accept orders for new ISDN lines.  They will also not make any changes to existing lines and will start charging more for the service.

Taking the place of ISDN will be a variety of Ethernet/IP based audio transmission methods.  As technology evolves, this makes sense.  The quality of ISDN and the bidirectional nature was a vast improvement over the old system  5/7/10/15 KHz point to point analog lines.  The one downside, ISDN equipment was expensive and the service was expensive to install and operate.

High speed internet is available in almost every business and venue.  Many times, there is no cost to access it and equipment is relatively inexpensive.  Depending on the equipment, CODEC, and speed, it can sound almost as good as ISDN.  For those opposed to using the public network due to reliability issues, there is always frame relay.

Time moves on, so buy your IP CODECS now.

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.

T-1 outage

One of our stations relies on a T-1 (DS-1) to relay audio from the studio to the transmitter site (STL).  This station started as a piece of paper, no format, no staff, no real estate, no studio equipment.  There was a transmitter and an antenna installed on a leased tower site.

That being said, corners were forcibly cut.  Instead of installing a microwave STL system, a T-1 was ordered because we had a T-1 multiplexor.  Fast forward several years… The station is now successful, making a decent amount of money and having a popular format.

The station has two T-1 circuits on different cables with an automatic switcher.   Yesterday afternoon, the inevitable happened, both T-1s went out, along with most of the other TELCO circuits in the surrounding area.  A construction crew cut two 3600 pair cables a mile down the road.  The TELCO is racing to restore the service to all of the tenants on that tower by rigging a temporary aerial cable.

TELCO trucks, courtesy of <a href=Now the mad scramble ensues with conflicting requirements from the wacky program director.  Screw it, I grabbed one of the AudioVault express machines and took it to the transmitter site.  They are back on the air with a radio station in a box playing music until the T-1 gets fixed.

This site has had numerous problems since we have owned it.  In the 5 years since we launched the format, there have been six T-1 outages longer than 24 hours.  For back up, we have tried an ISDN line, a 3G wireless card in a computer, and a second T-1 circuit.  None of these have proved reliable as most circuit outages involved a cable cut, and multiple circuits were effected.

The real solution is a microwave STL, either a conventional 950 mHz system, or a 2.4 or 5.8 gHz last mile system.  Either would work better than what we have now.  Station ownership, they don’t want to hear it.

Update: This took until Friday, September 4th to repair, for a total outage of 9 days, 2 hours and 26 minutes.  During that time, the station remained on the air with the AudioVault server at the transmitter site and the program director updating it twice per day with voice tracks and commercials.

Axiom


A pessimist sees the glass as half empty. An optimist sees the glass as half full. The engineer sees the glass as twice the size it needs to be.

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
~1st amendment to the United States Constitution

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
~Benjamin Franklin

The individual has always had to struggle to keep from being overwhelmed by the tribe. To be your own man is hard business. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
~Rudyard Kipling

Everyone has the right to freedom of opinion and expression; this right includes the freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers
~Universal Declaration Of Human Rights, Article 19

...radio was discovered, and not invented, and that these frequencies and principles were always in existence long before man was aware of them. Therefore, no one owns them. They are there as free as sunlight, which is a higher frequency form of the same energy.
~Alan Weiner

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