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Decommissioning transmitters

I was at a transmitter site a few days ago scrapping a Continental 816-R1 transmitter and started thinking (always a dangerous thing) about how many of these units I have decommissioned over the years.  It turns out, quite a few:

Make/Model Year new* Year removed Station Disposition
GE BT25A 1948 1994 WPTR Donated/scrapped
Gates BC5P 1960 2004 WWLO Donated
Harris MW5A 1982 2000 WLNA Scrapped
Gates BC1T 1961 2001 WLNA Donated
Harris FM20H3 1972 2001 WYJB Scrapped
RCA BT1AR 1960 2001 WROW Donated
Harris BC1G 1972 2001 WDFL Abandoned
Harris FM20H3 1971 2005 WHUD Scrapped
BE FM30A 1988 2005 WHUD Cannibalized
Harris FM5G 1972 2008 WSPK Scrapped
Mc Martin BF3.5K 1976 2011 WCTW Scrapped
RCA BTF-10ES 1978 2011 WRKI Scrapped
Gates BC1T 1964 2011 WINE Scrapped
Continental 315F-R1 1985 2013 WVMT Donated
Collins 813F 1975 2014 WKXZ Scrapped
RCA BTA1AR 1965 2014 WCHN Scrapped
Collins 813F2 1978 2015 WKXZ Scrapped
Collins 830D-1A 1968 2014 WKXZ Scrapped
Harris FM20H3 1972 2013 WYJB Scrapped
Harris BC5HA 1973 2013 WROW Scrapped
Harris FM10H 1971 2013 WMHT-FM Scrapped
Harris FM2.5H3 1973 2015 WEXT Scrapped
Mc Martin BF3.5K 1972 2014 WSRK Scrapped
CCA FM5000G 1980 2015 WTBD Scrapped
RCA BTF1E 1972 2016 WZOZ Scrapped
QEI 695T3.5 1996 2015 WBPM Scrapped
QEI 695T5 1996 2015 WBPM Scrapped
Harris HT3.5 1997 2015 WUPE-FM Scrapped
Harris Z5CD 1997 2015 WXPK Cannibalized
Energy Onix SSA1000 2000 2015 WDHI Cannibalized
Harris MW1 1982 2016 WPUT Abandoned
Mc Martin BF1K 1982 2016 WSUL Scrapped
Mc Martin BF3.5K 1982 2016 WSUL Scrapped
Continental 816R1 1980 2016 WDBY Scrapped

*In some cases the “Year New” is a guess based on when the station went on the air.  Before you write me and say “But model XYZ transmitter wasn’t made until 19XX, I did not look at every name plate and write all the information down as I did this.

Like everything else, there is a process to this.

RCA BTA-10U AM transmitter

RCA BTA-10U AM transmitter

First of all, if the transmitter was made before 1978, the possibility of PCB capacitors and transformers exists. In the case of the GE BT25A, massive amounts of PCBs needed to be disposed of properly. According to current federal laws, ownership of PCBs and PCB contaminated items cannot be transferred. Thus, the transformer casings were cleaned out and taken to Buffalo to be buried in a PCB certified landfill.   Otherwise, most other transmitters, such as the RCA BTA-10, may have a few PCB capacitors in them and perhaps the modulation transformer.  Those items can be disposed of by calling an authorized environmental disposal company like Clean Harbors.

The rest of the transmitter is stripped of any useful parts.  Things like vacuum variable capacitors, rectifier stacks, blower motors (if they are in good condition), HV power supply contactors, unique tuning parts, whole control and metering boards, tube sockets, etc.

The remaining carcase is then disassembled and hauled off.  I got a guy that will do this for relatively little money.  He takes the transmitter back to his warehouse and cuts it up, sorts all of the various metals out, then takes it to the scrap yard.  This includes things like cutting all of the windings off of transformers and power supply chokes, sorting out the brass and copper tuning parts, etc.

Remember kids:

μ = 1/1,000,000, 10-6 or 0.000001

Microaggression: If the worst thing that happened to you is you suffered through one millionth of an aggression, you are having a pretty good day.

The 16 channel bi-directional STL

As a part of our studio build out in Walton, we had to install a high capacity STL system between the studio and transmitter site. Basically, there are five radio stations associated with this studio and the satellite dish and receivers are going to be located at the transmitter site.

The audio over IP gear is getting really sophisticated and better yet, more reliable.  For this application, we are using a Cambium networks (Motorola Canopy) PTP-250 radio set and a pair of Wheatstone IP88 blades on either site.  Since there is quite a bit of networked gear at the transmitter site, the IP88’s will live on their own VLAN.  The PTP-250’s will pass spanning tree protocol, rapid spanning tree protocol, 802.1Q and other layer two traffic.

The Wheatsone IP88A blades are the heart of the system.  Not only do they pass 16 channels of audio, we can also pass 8 logic closures bi-directionally.  This is key because we are shipping satellite audio and contact closures back from the transmitter site.  The IP88A set up is fairly easy, once the IP address is entered.  The web GUI is used for the rest of the configurations including making the connections between units.

Pair of Wheatstone IP88A AoIP interfaces

Pair of Wheatstone IP88A AoIP interfaces

The switches are managed units.  The switchports need to be set up via command line to pass VLAN traffic.  There is an appendix in the IP88 manual that outlines how to do this with various manages switches.  This is the most important step for drop out free audio.  The switchports that connect to the two radios are set up as trunk ports using either VTP or 802.1Q.

Cambium PTP-250 5.8 GHz out door units

Cambium PTP-250 5.8 GHz out door units

The PTP-250 radios were already on hand, new in box.  They are built really well and look like they should not break in a year or so.  These particular units are connectorized, therefore an external antenna was needed.  There are many such antennas, this system ended up with a RF Engineering & Energy 5150-5850 MHz dual polarized parabolic dish with RADOMES.  RADOMES are necessary to prevent ice or snow build up in the winter.

RF Engineering & Energy 5150-5850 MHz dual polarized parabolic dish with LMR400 jumpers

RF Engineering & Energy 5150-5850 MHz dual polarized parabolic dish with LMR400 jumpers

STL link dish installed

STL link dish installed

1 1/2 inch EMT going from TOC to roof

1 1/2 inch EMT going from TOC to roof

Since the path is only 3.37 miles (5.43 kilometers), I set them up with a 40 MHz wide channel.  This is a rural, small town setting.  When I looked at the 5.8 GHz band on a spectrum analyser, it looks fairly uncongested.  These are MIMO single or dual payload selectable.  I will try them as single payload units, since the path is short and the band uncongested.  This should keep the throughput high.

Studio to transmitter site LAN extension

Studio to transmitter site LAN extension

The PTP-250’s use POE injectors in mounted in the rack rooms.  CAT5e shielded cable with the proper connectors properly applied is a must for lighting protection.  The PTP-250 units came with Cambium PTP-LPU lightning protectors.  I also installed Polyphaser AL-L8XM-MA type N surge suppressors on each RF port of each PTP-250.

Engineers hate this

Apparently, this coaxial cable has a hot spot:

7/8 inch air dielectric coax with jacket melting off

7/8 inch air dielectric coax with jacket melting off

The back story:

I received a text this morning that one of our clients station “had a lot of static on it, it might be off the air.” Upon arrival, I found the Nautel VS2.5 transmitter with 0 watts forward power and an output network fault. Reset the transmitter and the forward power and reflected power increased together, triggering another output network fault. I was able to turn the transmitter power down to 100 watts, at which point it stayed on, with 50 watts reflected power.  I also noted the dehydrator running continuously and 0 PSI line pressure.

Crap.

I wandered around the back of the building where the coax goes out to the tower and discovered the dripping plastic from the melted jacket.  I reached up and first checked the cable to see if it was warm (it was not).  Then I shook it and heard what I thought was water sloshing around inside.  This is the original Andrew 7/8 inch cable from when the station signed on in 1972 or so.  Very likely that further up the tower, something has chaffed through the outer jacket and shield, allowing water into the cable.

I drilled a small 5/32 inch hole at the lowest point in the cable before it enters the building.  The result was a steady stream of water, which was aided by some additional pressure from a spare N2 tank.  I let it drain while I ran down to town and got some lunch.  I came back a half an hour later, turned the transmitter on and was satisfied to see 100 watts forward power with 1 watt reflected.  I ran the transmitter up to full power for a while, then deciding discretion is the better part of valour, turned it down to half power; 820 watts which nets 8 watts reflected power.

Needless to say, the transmission line needs to be replaced as soon as possible.

Came as a stock item

So, I wore out another car and it was time to get a new one. Unexpectedly, the new car came with one of these fancy gizmos:

HD Radio as a stock item

HD Radio as a stock item

This is not the first HD radio I have owned, the Jeep Cherokee had one that I install myself. This is the first time it came with the car and I didn’t even mention it to the sales guy.

A few observations:

  • Many stations’ HD1 channels don’t sound very good, they are either shrill and tinny, or not synced with their analog counterpart.
  • There still aren’t very many station transmitting HD Radio; FM stations are either NPR affiliates or belong to a few larger corporate owners.  The AM stations are few and far between.
  • AM HD Radio still has numerous problems in the mobile listening environment.
  • Many of the HD 2/3 don’t sound very good; low audio levels, muffled modulation, low bit rate audio, etc.  The only exception that I have found so far is Vermont Public Radio’s classical format, transmitted on the HD2 of WVPS, Burlington.
  • HD2/3 channels mainly serve as “translator loophole” stations, AKA “Metro Stations”

As far as the new ownership by DTS goes; I will reserve judgement until they do something with it.

Common’ Baby

Who is that old guy standing next to Chubby Checker?

Chubby Checker and yours truly

Chubby Checker and yours truly

Hey, that’s me!

And never will you meet a nicer gentleman than Chubby Checker.

Studio Buildout, Part II

Some pictures of the studio build out in progress.

Counter top mounted

Counter top mounted

This is the counter top, mounted on a riser with the wire way cut into it. These counter tops will have AudioArts Air4 consoles installed on them.

AudioArts Air4 console with microphones

AudioArts Air4 console with microphones

Studio is taking shape. Console mounted with microphones. The rack mounted equipment goes in the Middle Atlantic rack under the counter top to the left of the console.  That rack is on casters so it rolls out to get access to the back of the equipment.  We have pretty much done away with cart pods or other counter top equipment housings.  The automation and other computers will be mounted in the rack room and extended to the studio with IP KVM extenders.

Sub Panel with manual transfer switch

Sub Panel with manual transfer switch

We installed a small Square D sub panel and manual transfer switch. This is to prevent the “Space Heater” outages, you know, when the morning show guy plugs a space heater into the same circuit as the console or computer, trips the breaker, then calls you because they are off the air. Yeah, good times.

In addition, the manual transfer switch will allow them to use a good portable generator if there is a prolonged power outage. On the bottom of the switch I installed a 30 amp twist lock input receptacle.

Since the building is older, the grounding buss was installed and wired directly to the ground at the service entrance panel.   The building sub panel for this floor is using conduit for the ground conductor back to the service entrance panel, which used to be code compliant but no longer.

5.8 GHz dish with non-penetrating roof mount

5.8 GHz dish with non-penetrating roof mount

STL/LAN extension dish installed on roof top. I used an old non-penetrating roof mount for a four foot satellite dish.  The building owner was very specific about not having anything puncture the new rubber membrane roof.  Thus, the heavy rubber mats and sand bags instead of cinder blocks.  These stations will be using a Cambium PTP-250 system for STL/TSL and LAN extension. This will haul program audio for five radio stations plus satellite backhaul and remote control. It is a relatively short path with the FM tower visible from the roof top.

5.8 GHz path to FM tower

5.8 GHz path to FM tower

It was kind of hazy when I took this picture, but if you look really close, you can see the FM tower out there on the hill top.  The path is 3.37 miles (5.43 KM).  With a 40 MHz channel width, that should net about 175 Mbps bi-directionally, which is more than enough to do what we want.  This set up will require a pair of managed switches and some VLAN configuration, which I will post separately.

No, this time we really mean it

The FCC is stepping up enforcement on pirate radio. They have released an enforcement advisory, which you can read here.

The advisory starts out like this:

WARNING: Unauthorized Radio Broadcasting is Illegal
Persons or Businesses Operating “Pirate” Broadcast Stations
Are in Violation of Federal Law and Subject to Enforcement Action

Okay, so when you stop laughing, here is what will really happen: They will go out, bust a few pirates, issue larger than normal Notices of Apparent Liability, collect none of the money from them and call it a huge success.  I doubt very much that the FCC or congress has the wherewithal to wage an all out effort against pirate broadcasting. This is the same FCC that eliminated most of its field enforcement agents and closed most of their field offices.  But that doesn’t matter either, because the NYC field office is still open and within a ten mile radius of that, there are likely a dozen or more unlicensed broadcasters.

In the mean time, if you are a licensed broadcaster, God forbid you accidentally miss a Required Monthly Test or have an unlocked tower fence.

It is like the city police force that sits on a stop sign writing tickets to otherwise law abiding motorists when the next block over, kids are out in the street openly selling bricks of heroin.  Meanwhile, the chief of police sits in his office furiously typing blistering memos saying that the sale of heroin is illegal.

Comacho 2016

I know who I am voting for:

President Dwayne Elizondo Mountain Dew Herbert Camacho

President Dwayne Elizondo Mountain Dew Herbert Camacho

If you have not watched Idiocracy yet, Netflix it (or youtube it).

Seriously, I can’t see anyone worth voting for, I suppose I will have to Johnson it again.

Studio Buildout, Part I

We are in the process of building a couple of new studios for one of our clients. This one involves a small market combo of one AM and four FM stations.  These stations were formerly located at one of the transmitter sites, two miles outside of town on top of a large hill.  That site could be difficult to get to during the winter and the building itself was not in the best of shape.  Thus, plans were made to move the studios to a better location.  Fortunately, we discovered that right in the village there are several suitable office buildings.

Any worthwhile project needs to be planned for.  The first consideration is the Studio to Transmitter Link (STL) paths.  Since this is a radio studio, it makes sense to located it where viable RF STL paths exist.  One might be surprised by the number times the issue of bad or non-existent RF STL paths has come up during these types of projects.

Studio to transmitter site LAN extension

Studio to transmitter site LAN extension

The next thing to check is the satellite path.  The plan right now is to keep the satellite dishes at the transmitter site, however, at some point in the future we can relocated the satellite dish to the roof of the studio building if desired.

AMC-8 satellite path

AMC-9 satellite path

The floor space was measured out and I drew out a floor plan:

Walton Studio floor plan

Walton Studio floor plan

Before we started work, all of the walls were painted and new carpeting installed.

Almost nothing at the old studio is worth keeping. Thus, all of the furniture, consoles, racks, STLs, and other equipment needed to be ordered.  A local kitchen company traded out the counter tops, which we picked up at their facility and delivered to the studio ourselves.

Studio counter top

Studio counter top

We will build risers for these on site then mount the consoles and such.

New Studio Equipment

New Studio Equipment

In the mean time, most of the new studio equipment has been ordered and delivered. There are still some outstanding items that have not arrived, but I am assured that those are in process and should be showing up shortly.

Used equipment racks

Used equipment racks

These equipment racks came from another market, but are in good shape.

I had a good meeting with the building owner regarding roof access, a sub panel for the racks and studios and other issues.