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Accidents, mistakes, mishaps and other tales

Lets get started:

Results of a deer vs automobile accident

Results of a deer vs automobile accident

It does not look like much, however, that is about $5,500.00 worth of damage. What you don’t see is the mashed oil cooler and radiator. This happened on my way from one place to another during the early morning hours. I was traveling at about 55 MPH when a deer bolted from the woods and entered the roadway from the right. I did not have time to break.

In a ditch

In a ditch

A momentary lapse of attention causes loss of $80.00. I think I was adjusting the defroster as I was driving down the road when suddenly, I felt the car tilt over to an alarming degree. You can see the tow truck getting ready to pull it out. Fortunately, there was no damage to the vehicle.

Troubles with the neighbor

Troubles with the neighbor

This is on the access road to one of our transmitter sites. The station has a legal right of way through this property, however, the neighbor seems to object. I spoke with him and showed him a copy of our deed, he has since changed plans.

One side of a balanced audio connection disconnected

One side of a balanced audio connection disconnected

This is the downside of using category cable to make audio connections. The wires are not as rugged as say Belden 8451. This was causing problems because it is at an AM studio/transmitter site.

Burned 30 amp three phase contactor

Burned 30 amp three phase contactor

Three phase, 30 amp, 240 volt contactor installed in a 480 volt system. Lasted a few years, anyway.

White face hornets nest

White face hornets nest

New tenants on one of our towers. This is a white faced (or bald faced) hornets nest. They are really paper wasps, but that difference aside, these beasts are nasty, aggressive and have a painful sting. Normally, I am a live and let live kind of person, but in this case, they gotta go.

Dummy load attached to plywood

Dummy load attached to plywood

This is at one of our AM clients site. Somebody, quite some time ago it seems, made this test load for a 1 KW AM transmitter. It is very nice, carbon ceramic resistors, 50 ohms and surprisingly little reactance. Then they attached it to this piece of plywood. As one can surmise, the load gets quite hot under full power, full modulation conditions. We remounted this in a cage type enclosure and bolted it to the cinder block wall.

Scala PR-950U cross polarized

Scala PR-950U cross polarized

The client at this station is complaining of intermittent STL drop outs and low signal strength at the receive end. Found this Scala PR-950U antenna mounted for vertical polarization, but the antenna element is horizontally mounted. We’ll call it “vorizontal.”

Ribbon cable from a Cummins 135 KW generator

Ribbon cable from a Cummins 135 KW generator

This was discovered during routine maintenance and thankfully not during a power outage. Mice got into the control box of a newish Cummins 135 KW generator and chewed through what looks like a data buss cable. The generator would not run and the cable and control board needed to be replaced.

Bulging capacitors

Bulging capacitors

There is more bulging capacitors removed from flat panels monitors.

And so on…

Transmitter site re-hab

One of the reasons for the recent lack of posts; I have been busy rehabilitating several transmitter sites for various broadcasting companies. These are mostly FM transmitter sites and vary in power from one kilowatt to twenty six kilowatts ERP.  I enjoy project work, but I have been driving hither and yon, racking up 27,000 miles on my new car since last August.

Subaru Crosstrek XV at remote transmitter site, somewhere in rural New York

Subaru Crosstrek XV at remote transmitter site, somewhere in rural New York

So, here is one transmitter site that I just finished; WFLY, Albany, New York.  Removed Collins 831F2 transmitter which was functioning as a backup and installed new Broadcast Electronics FM20S.  The Continental 816R2 is becoming a little bit long in the tooth for a main transmitter, being new in 1986.  Thus, it was time to install a new unit, and I like the Broadcast Electronics solid state and tube designs.  With the BE AM and FM solid state units, their simplicity is their beauty.  We service many BE transmitters, some are thirty years old and are still supported by the manufacturer.

WFLY transmitter building, New Scotland, NY

WFLY transmitter building, New Scotland, NY

The BE FM20S transmitter is actually two FM10S cabinets combined with one controller.  Each cabinet requires a 100 amp three phase mains connection.  This station’s TPO is 11.5 KW, so there is plenty of head room in case the owner’s ever want to install HD Radio or replace the three bay antenna with a two bay unit.

WFLY main transmitter, Broadcast Electronics FM20S

WFLY main transmitter, Broadcast Electronics FM20S

In transmitter cabinet two, above the exciter is room for HD equipment.

BE FM20S exciter housing

BE FM20S exciter housing

I also reworked the coax switches to provide easier implementation of the backup transmitter.  Basically, the main transmitter is on the main antenna, the backup transmitter is on the backup antenna.  We can move the second coax switch to test the backup into the dummy load.  We can move the first coax switch to change antenna feeds.

WFLY backup and main transmitters

WFLY backup and main transmitters

Pretty standard setup.

WFLY RF path diagram

WFLY RF path diagram

We moved the Collins 831F2 from Albany to here to replace another, dead Collins unit at WKXZ in Norwich, New York.  This transmitter is forty years old, but still runs reliably.  Of course, doing this work in the dead of winter added a degree of difficulty to the job, as the roads to both the WFLY and the WKXZ transmitter sites needed work to make them passable for a moving truck.  In the end, we used a skid steer with forks on it to get the transmitter up the final hill and into the small WKXZ transmitter building.

Collins 831F2 transmitter, WKXZ, Norwich NY

Collins 831F2 transmitter, WKXZ, Norwich NY

Collins 831F2 transmitter

Collins 831F2 transmitter

The WKXZ transmitter building interior is floor space challenged. It is located next to a former TELCO microwave site which has a guyed tower.

Drone footage of tower demolition

Watching a tower drop from a different perspective:

Looks like a World Tower Utility 80.

The IP enabled transmitter site

This is a project that we have been working on, weather permitting, for the last month. Basically, it called for installing this Nautel VS2.5 transmitter, mod monitor, remote control and audio processor:

WEXT Nautel VS2.5, Amsterdam, NY

WEXT Nautel VS2.5, Amsterdam, NY

The common thread here; each piece of new equipment has a web interface.  More and more, HTTP is being used to monitor and control transmitters, audio processors, STL’s, consoles, satellite receivers, etc.  Port 80 services (HTTP) are nice, but I think I would prefer port 443 (HTTPS).  Secure HTTP has a whole set of additional requirements, so it is understandable why manufactures do not use it.  However, it is only a matter of time until some problem arises…

Nautel VS2.5 Web AUI

Nautel VS2.5 Web AUI

Burk ARC Plus web interface

Burk ARC Plus web interface

Telos Omnia One web interface

Telos Omnia One web interface

I like the Nautel AUI, especially for any station running HD Radio.  In this setup, there are multiple control and monitoring points available via the LAN at the studio.  The Omnia One is set up to take the AES input from the Harris IP Link as the main feed and fail over to the analog output from the Inno Tuner as a backup.  The Inno is set to WMHT-FM which broadcasts the WEXT format on the HD-2 channel.

This setup is pretty slick, especially in light of the equipment it is replacing:

Harris FM2.5H3, WEXT Amsterdam, New York

Harris FM2.5H3, WEXT Amsterdam, New York

Anyone feeling Nostalgic for a Harris FM2.5H3?

No?

I didn’t think so.

Brother, could you help a pirate out?

It is not news that the FCC has its hands full with the FM pirates in the NYC area, particularly Brooklyn. On any given night, as many as thirty unlicensed signals can be heard, jammed between the commercial and non-commercial broadcasters in the FM band.

I am quite sure that other parts of the country have similar pirate problems.  I do not see the FCC getting much more funding for enforcement purposes.

John Anderson asks; perhaps a pragmatic approach?

For most engineers, this will be a non-starter.  Engineers (and other technical people) tend to see things in binary; on/off, right/wrong, black/white, legal/illegal, working/broken, etc.  It is the nature of logic and dealing everyday operating status’ of technical equipment.  A transmitter that is halfway working is broken.  There is very little grey area in the interpretation of these things, nor is there very much human element.  One cannot reason with a broken piece of equipment; it is to be either repaired or replaced.

Helping a person engaged in what is ostensibly an illegal activity, no matter how pragmatic such help might be, or how just or helpful the illegal activity may be to the community, would not be something that most radio engineers that I know would want to take part in.

Truth be told, some good might come from helping pirate broadcasters clean up their act.  Over modulation, spurious emissions, poor quality transmitters all create bigger problems for everyone else.  The moral dilemma is what type of help to offer and can this or any technical advice then be used to make bigger and better pirates.

I don’t know, but it may be time to start thinking about things like this…

HD Radio development Stasis

I have been working on an HD Radio installation these last few days.  This particular installation was manufactured by Broadcast Electronics.  Some 13 years into the HD Radio development cycle and the implementation still seems like a kluge to me.  To get some idea; to transmit a digital HD Radio with added sub-channels, the following equipment is needed:

  • HD Data importer, off the shelf computer with a sound card and specific software from iBquity.  This is used to import the audio for the HD-2 and HD-3/4 channels.  Runs on Windows (Win 7), Linked to the exporter via IP ethernet
  • HD Radio exporter, another specialized computer with a sound card.  Frames the HD Radio data and adds PID, etc.  Runs on Mandrake Linux, communicates with the exciter via data connection.
  • HD Radio exciter; like other exciters, generates RF and modulates it.
  • HD Radio transmitter; essentially an FM transmitter designed to run as a linear amplifier.

The HD Transmitter part can come in several configurations, including low level combining, high level combining or using a separate antenna for digital and analog signals.

Broadcast Electronics HD Radio transmission system

Broadcast Electronics HD Radio transmission system

None of this is news, of course.  My point is, after ten years, there does not seem to be any further development in HD Radio technology.  In the mean time, competitors are not standing still.  The mobile wireless industry has evolved several times during the same time period; 3G, 4G and LTE have been successfully deployed and widely adopted by mobile phone users.  Truly, mobile data is the real competition to terrestrial broadcasting.

The HD Radio transmission process is an overly complicated patchwork of hardware and software.  The importer in particular seems substandard.  It’s function is to run a bunch of small programs, each doing some small part of the importing process.  The web-admin used Internet Explorer, who uses Internet Explorer anymore?

Since the HD Radio inception, little or no further development seems to have taken place.  There are features, such as album art, program data, traffic data, etc but the system interface is weak, the hardware clunky, the data paths fragile, the operating system outdated, the typical installation is a compromise between cost and available floor space at the transmitter site.

HD Radio is also expensive to deploy and proprietary.  There is little compelling reason to listen to HD-1 channels because the programming is identical to the main analog channel.  HD-2, 3 and 4 channels seem to be mostly used to generate translator feeds, which again, are available with an analog radio.  This use of HD Radio actually damages uptake because, If all the HD Radio sub channels are available on FM analog frequencies, then why even bother with an HD Radio receiver?

Thus the forces at work in the development of HD Radio seem to have reached equilibrium:

Consumer apathy + expensive deployment = 16% uptake on FM and 6% uptake on AM1

The digital radio roll out has been stuck at those levels for many years.  Unless something changes, FM HD Radio will be limited to translator program origination and distribution.  AM HD Radio will go the way of AM Stereo.

1: FCC data on HD Radio deployment; 1,803 of 10,727 FM stations and 299 of 4,708 AM stations have installed HD Radio as of December 31, 2014.

Winter! Is upon us….

What better time to take the gondola to K-1? None, none at all.  We do work for the two radio stations that are on the peak of Mount Killington, near Rutland, Vermont.  In the summer, usually we can drive up there in a four wheel drive truck.  In the winter, the gondola is the way to go.  On this day, there was a 48-56 inch base, light north winds and air temperature around 10° F (-12° C) .

This is not my video, I did not have enough memory on my SIM card to film a video and I didn’t bring my expensive camera. However, this is a good example of the ride:

Not a bad way to get to a transmitter site, all things considered.

Ride up to Killington Peak

Ride up to Killington Peak

View from Killington Peak

View from Killington Peak

View from Killington Peak

Transmitter buildings on Killington Peak

View from Killington Peak

View from Killington Peak

View from Killington Peak

Tower from Killington Peak

Killington STL dishes

Killington STL dishes

ERI antenna, WZRT/WJJR Killington VT

ERI antenna, WZRT/WJJR Killington VT

The reason for the trip today; repair work on the Nautel VS2.5 transmitter. All three power supplies and the power supply summing board needed to be replaced.

MPX over IP

In the progression from Circuit Switched Data to Packet Switched Data, I can think of many different applications for something like this:

FMC01 MPX to IP CODEC

FMC01 MPX to IP CODEC

The FMC01 MPX to IP encoder can be used for multi-point distribution (multi frequency or same frequency network) of FM Composite audio, or as a backup solution over a LAN bridge, LAN extension, or public network.  I can think of several advantages of using this for a backup when composite analog STL’s are in use.  There are many compelling reasons to extend the LAN to the transmitter site these days; Transmitter control and monitoring, security cameras, office phone system extensions, internet access, backup audio, etc.  I would think, any type of critical infrastructure (e.g. STL) over a wireless IP LAN extension should be over a licensed system.  In the United States, the 3.6 GHz WLAN (802.11y) requires coordination and licensing, however, the way the rules are set up, the license process is greatly simplified over FCC Part 74 or 101 applications.

Another similar CODEC is the Sigmacom Broadcast EtherMPX.

Sigmacom Broadcast EtherMPX CODEC

Sigmacom Broadcast EtherMPX CODEC

Features include:
• Transparent Analog or Digital MPX (MPX over AES), or two discrete L/R channels (analog or AES).
• Built-in MPX SFN support with PTP sync (up to 6.000km in basic version). No GPS receivers!
• Unicast or Multicast operation to feed unlimited number of FM transmitters with MPX from one encoder.
• Linear uncompressed PCM 24-bit audio.
• Very low audio latency: 2,5mS in MPX mode.
• Perfect match with Sigmacom DDS-30 Exciter with Digital MPX input.
• Can be used with high quality 802.11a/n Ethernet links.
• DC coupled, balanced Analog inputs & outputs with -130dBc noise floor.
• No modulation overshoots due compression or AC capacitor coupling.
• Decoder provides simultaneously Analog & Digital output for transmitter redundancy.
• Aux RS232 serial transparent link, Studio to Transmitter.
• Auto switchover to Analog input when Digital signal is lost.
• Centralized remote control & management software

One last thought; separating the CODEC from the radio seems to be a good idea. It allows for greater flexibility and redundancy. Using an MPX type STL allows sensitive air chain processing equipment to be installed at the studio instead of the transmitter site.

Well, crap

Radio Shack Store, Courtesy of Wikipedia

Radio Shack Store, Courtesy of Wikipedia

Radio Shack (AKA, RadioShack, The Shack, Tandy Corporation, Realistic, Optimus, etc) appears to be filing for Bankruptcy if the Wall Street Journal and Reuters is to be believed.  I see the words “private equity firm” in the article, that does not bode well.

Radio Shack of late has become a glorified cell phone store.  It used to be one could get some emergency repair parts, an FM antenna or a CB radio as the need arose.  As a young lad, it was fun to poke around and look at the various radio kits and other assorted fun things.  My first shortwave radio was a kit from Radio Shack; assembly finished just in time to hear the Vatican Radio’s announcement that Pope Paul IV had died.

What happened to Radio Shack is fairly typical; what was once a niche market for hobbyists and experimenters tried to go main stream and lost their core customers.  There are still plenty of electronics hobbyists out there, look at the Amateur Radio community as an example.  Yet, that market was abandoned for the more lucrative general consumer electronics market.  Unfortunately, Radio Shack never produced high quality stuff, so their reputation in the consumer electronics market was not that great.  Thus, not being known for anything, they slowly slipped into irrelevance.

Don’t try this at home, kids

Happy New Year, and stuff.

I found this interesting little video on Youtube recently:

That has to be a fairly high powered AM radio station to have that effect. According to the video, this is in Ukraine.

Other than generating RF burns to the hands, there is also the issue of exposure to non-ionizing radiation causing body tissue heating. Then there is the potential broadband RF interference from the arcing plant matter. This can cause interference to STL’s and other receivers.