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Happy Independence day, Extremist

Today is July 4th. We here in the United States like to remember this as the day when a bunch of upstart yokels from the colonies had the unmitigated gall to decide we wanted to rule ourselves.  Terrible thing, that.  It sets a bad precedent for the other subjects, some of whom may decide that they want self rule as well.  Allow that to happen and pretty soon, the whole empire will be in shambles.

So, there was a war.

It became pretty brutal in this area; loyalists and indians banded together to pillaged the countryside.  Families massacred, women shot down, children scalped, old men hung from trees, etc.  Part of the local history, although not really the stuff they teach in school these days. It happened, none the less.

Therefore, we celebrate our independence and revel in our freedoms that were so hard won.  Freedoms to do things like speak our mind, own firearms, enjoy limited government intrusion in our lives.  As human beings, we have rights to legal safeguards that ensures the legal system will not be abused.  We enjoy the freedom to travel within our own boarders unmolested.  We can worship or not worship in anyway we choose.

We are free, for example, to exchange ideas and develop technology that benefits us and others.  Free to learn about things like open source software and even help write the code.  Imagine my surprise then, to find out by visiting a website called “Linux Journal,” I am now an extremist?  I have frequented many such Linux websites, forums, subreddits, and so on over the years, all in an effort to better understand and apply the open source operating system.  I am now, apparently, on a watch list.

This is an article from ars Technica that outlines the NSA program: The NSA thinks Linux Journal is an Extremist Forum.

This is an article from the Linux Journal website: Are you an Extremist?  WARNING: If you click that link, then clearly you are.

My only conclusion to this is open source software is bad because of TEH TERRORISM!!11!!! Well, that and it appears to be eating into Microsoft’s and Apple’s market share.

LJ-Extremist-black-stamp

So, put me on a watch list and make sure you spell my name right. You can track everywhere I go.  Hell, I’ll even making entertaining for you.

Happy Fourth of July, Extremist!

The efficacy of the computer generated voice

I was just listening to the latest broadcast of severe thunderstorm and tornado warnings rolling in across WXL-37 for upstate NY:

Trouble is a brewing

Trouble is a brewing

It looks a little bit hairy to the north.  There is a lot of rumbling around to the west of us and we are prepared to head for the basement in event of a tornado in this area.

At some point in time, somebody decided that computer generated voices were exactly right for emergency communications. Never mind some of the quirks that can be encountered.  These are mostly pronunciation errors for places like Saugerties, normally spoken as Saw-ger-tees but the NOAA computer voice says S-ouw-jer-tees.  That is understood well enough, but frankly, there are other place names that go by so fast that I cannot make sense of what the computer is saying.

Another good example of this is the Coast Guard’s computer voice confusion around the word “November.”  In the military (NATO) phonetic alphabet, November is the word used to express the letter N.  For some reason, the word itself seems to be a bit of a mystery to the computer, which sometimes renders the word November as “NOVEMBER OSCAR VICTOR ECHO MIKE BRAVO ECHO ROMEO.”  For those of us who have been in the military, this makes perfect sense.  Why just say “November” when you can say much more, waste time, and confuse the unaware.  This particular computer voice is nick named “Iron Mike.”

Computer generated voices can be hit or miss.

Then there is the computer voice from Shannon VOLMET:

Even on HF Single Side Band, that voice is clearly more understandable than the NOAA voices in use today. The issue is, many broadcast stations now use the NOAA computer voice to broadcast weather alerts to their listeners.  If I were driving in my car with lots of background noise, I likely would not get most of the information being relayed by the broadcast station via EAS.  I suppose gone are the days of a professional broadcaster’s voice clearly imparting information and comforting the listeners during time of calamity.  Sigh.

The rotary phase maker

I alluded to this in an earlier post: Open Delta three phase service.  Some transmitter sites are fairly remote and three phase power is not available.  Occasionally, with lower powered radio stations, this is acceptable because those transmitters can be configured to run on single phase power.  However, almost any transmitter above five kilowatts or so will require three phase power.  This is the case at the WQBJ transmitter site in Palatine Bridge, NY.  The site is located in the middle of farm land and only has single phase service.  The nearest three phase service is several miles away and the utility company wants several hundred thousand dollars to upgrade the line.

WQBJ transmitter site electrical service

WQBJ transmitter site electrical service

The station is a class B FM with a six bay full wave spaced antenna.  Even so, the TPO is 17 KW, which makes some type of three phase service a requirement.

WQBJ six bay Shively 6810 antenna

WQBJ six bay Shively 6810 antenna

The main transmitter is a Broadcast Electronics FM30B, which is now 25 years old.

WQBJ main transmitter, Broadcast Electronics FM30B

WQBJ main transmitter, Broadcast Electronics FM30B

The backup transmitter is a CSI FM20T, which is almost forty years old.

WQBJ backup transmitter, CSI FM20T

WQBJ backup transmitter, CSI FM20T

Rather than do an open delta service, which is not desirable for several reasons, both transmitters have their own rotary phase makers.  From a reliability and redundancy standpoint, this is the right way to equip this site.  The rotary phase makers are essentially a motor generator combination which takes the split phase power and generates a third phase.

WQBJ phasemaster, backup three phase converter

WQBJ Phasemaster type T, backup three phase converter

Phasemaster parallel connection diagram

Phasemaster parallel connection diagram

The phasemaster is is a 40 KVA unit and is connected to the backup CSI transmitter

WQBJ Roto Phase, main three phase rotary converter

WQBJ ARCO Roto Phase, main three phase rotary converter

The Roto Phase unit for the main transmitter is actually two 40 KVA units connected in parallel through dry core isolation transformers.  Incidentally, the Roto Phase units need to have their bearings changed every ten years or so.  This requires the units be disconnected, placed up on their end.  To get the old bearing out, the housing has to be cooled with liquid CO2.  Both units are due for new bearings soon, which should be a pleasant job indeed.

Repairing the Nautel VS2.5 transmitter

The newish Nautel VS2.5 transmitter installed at WJJR had an RF module failure. This particular model transmitter does not have slide in RF modules as other Nautel transmitters do.  To fix this transmitter, it has to be pulled out of the rack, flipped over and opened from the bottom. The module replacement is very straight forward, there are five solder pads that connect to wires carrying the input, output, power supply and bias voltages.

Nautel VS2.5 transmitter RF modules and combiner

Nautel VS2.5 transmitter RF modules and combiner

The troubleshooting guide gives good instructions on how to check the PA MOSFETS with a DVM. I found that 1/2 of the device in PA1 was bad:

Schematic Diagram, NAPA31

Schematic Diagram, NAPA31

All in all, not a very hard repair. This was under warranty, so a replacement RF pallet was sent to the station without charge. The problem is more about where the transmitter is located:

Killington Mountain, Killington, VT

Killington Mountain, Killington, VT

Killington Peak is the second tallest mountain in Vermont, topping out at 4,235 feet (1,291 meters). In the winter, one can take the chair lift to the top. In the summer, the road is drivable with a four wheel drive. In those in between months, access to the top can be very tricky at best. We had a pretty wet spring this year, so the roads up the mountain are just now becoming passable for vehicles.

Even after reaching the parking lot, there is still a 10 minute walk to the peak, another 200 or so feet up a steep, rocky trail.

Further complicating things, this transmitter is wedged into this little shack, which holds; a BE FM3.5A transmitter (defunct WJJR), a Harris HT3 transmitter (WZRT), an ERI combiner, two racks of equipment (STL’s, Exciters, remote controls, etc) a backup QEI transmitter, an Onan generator transfer switch:

Killington Peak fire tower, WJJR WZRT transmitter building

Killington Peak fire tower, WJJR WZRT transmitter building

Both stations run into this ERI half wave spaced antenna:

WJJR WZRT ERI antenna

WJJR WZRT ERI antenna

It is very tight in this transmitter room. There is a new tower on Killington Peak, which is still under construction. At some point, the plan is to move into the larger building next to the new tower.

Killington Peak tower

Killington Peak tower

On a clear day, the view from the top is spectacular. On this day, the peak was in the clouds, so not so much:

Killington Peak view

Killington Peak view

It is a great site, the HAAT is 2590 feet (790 meters) and the stations carry forever on relatively low power outputs.

Friday Funnies; GOT edition

Nothing at all to do with radio, however, those who have been watching the HBO series Game Of Thrones will get this:

Winter is coming

Winter is coming

With a tie in to current events. I do hope this gets straightened out for the sake of our European friends.

Casey Kasem, R.I.P.

Casey Kasem has gone off to the big control room in the sky.  Wildly popular DJ, Scooby Do, something about American Top 40, bla, bla, bla.  Whenever I think of Casey Kasem, I think of this:

Get Don on the phone, and where are my pictures!

We have all worked with screaming DJ’s, almost nothing is worse than getting yelled at for something you have little or no control over.

Pro Tip:  If you feel you are about to go off on a tirade, turn the microphone off so it does not get up loaded to the internet and played back at your funeral.

For Sale?

I am working on a project, as you might have guessed by the lack of posts.  It seems like a good opportunity to actually, you know; earn a living.  The thing is, I need some start-up capital.  Not a ton of money per se, but enough that I do not have it readily available, waiting to be spent.  Which brings me to this: I think this website is worth something.

I have put several years worth of work into this, as I have stated before, it is more a labor of love than anything else.  The sponsored ads simply cover the cost of hosting, domain name renewals, plus a little extra that perhaps I can take my family out to diner once a year or so.  I know I probably place its value at more than it is worth.  That being said, I went to one of those website valuation tools, which gave me a value of $6,600 based on traffic, domain name age and original content.  It did not take into account the extra domain names registered, etc.

So, here it is; is there anyone out there interested in buying this site?  Perhaps another contract engineer or engineering firm that is interested in a well seasoned domain name that gets 700 to 800 page views per day.  Or somebody else?

This is what is for sale:

  • engineeringradio.us (2009)
  • engineeringradio.com (2007)
  • engineeringradio.org (2010)
  • engineeringradio.net (2010)
  • engineeringradio.info (2010)

690 blog posts on various topics and over 1,000 original photographs.

Contact me off line, if you are interested.

Fifth Generation WLAN

Like all data carrying technology, WLAN, or WiFi, continues to evolve into a better, faster and more robust platform.  The IEEE wireless ethernet specification 802.11ac combines all of the past developments, plus some added features, into one specification.  Here are some of the highlights:

  • Operation on 5 GHz only.  Many more available channels in this spectrum than in 2.4 GHz
  • Increased channel bonding making wider channels carrying more data.  In the 5 GHz spectrum channels are 20 MHz wide and do not overlap.  802.11ac allows for 40, 60, 80 or even 160 MHz channels.  This is great for short distances, longer distances will be prone to greater interference over wider channels
  • Modulation schemes that allow up to 256 QAM.  A 256 QAM constellation is going to look pretty crowded unless it is on a wide channel.  Again, this would be good for short distances.
  • Increased MIMO.  Up to 8×8 MIMO (Multi In Multi Out) which can greatly improve throughput.  MIMO means multiple transmitters and antennas in the same unit.  The first number is the transmitter count the second number is the antenna count.  Thus an 8X8 system will have eight transmitters and eight antennas.  This allowed beam forming by use of phased antenna arrays, which can greatly reduce multi-path
  • MU-MIMO (Multi-User MIMO).  Basically, the access point sends the data frame only to the desired host, thus instead of acting like an ethernet hub sending the frame to every connected host, the AP is acting more like an ethernet switch.
Comparison of 802.11n to 802.11ac

Comparison of 802.11n to 802.11ac

The goal of all of these modifications is to get gigabit transfer rates over WLAN.

What does all of this have to do with radio broadcast, one might ask.  That is a good question.

There are several applications that have to do with remote broadcasting.  Many sports areas, night clubs, or other likely places to be broadcasting from have WIFI installed.  Using a laptop with an AoIP client installed not only can connect to the studio for audio delivery, the same laptop can use RDP or VNC to control the station’s automation computer as well.  This means easier integration of the remote into voice tracked or syndicated programming.

Secondly, wireless LAN bridges between studio and transmitter site can act as a STL, a backup STL, a remote control return link, bridge for a network connected transmitter,  VoIP phone link, IP security camera back haul or almost anything else that can send ethernet data.  I have found it useful to simply have a computer available at the transmitter site, even if it is only to download manuals and what not.  We have taken several old Windows XP machines and reloaded them with a Linux variant and installed them at various transmitter sites.  It saves the trouble of having to download a manual on the smart phone then page back and forth across a really small screen to read it.  As for using unlicensed WiFi to link to a transmitter site; the link between the WICC studio and transmitter site runs a 78 Mbps most days.  This is a two mile link over mostly water.  I will say, when there is fog, the link rate drops to 32 Mbps, which is still pretty good, all things considered.

Of course, office network applications; laptop, tablet, smartphone and other personal devices.

Finally, Broadcast Engineers really need to keep abreast of networking technology.  There are many, many applications for WiFi units in the broadcast industry.

About the whole Net Neutrality thing

The Internet

The Internet

I suppose it comes down to asking the question; who owns the internet?  For that, there is no easy answer.  In order to clarify the question a little more, just what exactly is the internet?  So this is from wikipedia:

The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite (TCP/IP) to link several billion devices worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless, and optical networking technologies

That sums up the technical aspect fairly well. Thus, TCP/IP protocol stack seems to be intricate in the design and operation of the internet. The internet protocol suit was developed by ARPA (now DARPA or the Defense Advanced Research Projects Agency) as a way to link computers together across multiple OS’s and network types. It works very well. TCP/IP and related protocols are open source and are maintained by the IETF or Internet Engineering Task Force which is a standards organization.

Thus far, it looks like the software that runs the internet was developed with tax payer money, therefore, by way of reason, we paid for it, we own it.

However, this does not consider the physical infrastructure that makes the connection; the cables, routers and data centers that make the whole thing work. That infrastructure was installed and maintained by corporations, AKA “big data.” Companies with names like ATT, Verizon, Cogent, Sprint/Softbank, Century Quest, Global Crossings/Level Three, and NTT/Vireo. This is known as the information infrastructure. Again from Wikipedia, which sums the term up nicely as:

An information infrastructure is defined as a shared, evolving, open, standardized, and heterogeneous installed base of the people, processes, procedures, tools, facilities, and technology which supports the creation, use, transport, storage, and destruction of information.

The ownership of the physical infrastructure is a little more dicey because the US government has subsidized with tens or perhaps hundreds of billions of dollars of tax payer money. See also: Universal Service Fund.  It is difficult to nail down the exact figure because there so are many different programs, most having to do with broadband deployment.

To muddy the waters a little bit further, there is the Title I or Title II question.  Under telecommunications act of 1996, Title I services are defined as informational, which means optional.  Title II services are defined as telecommunications, or common carrier e.g. things like the PSTN (public switched telephone network or POTS).  It becomes a question of being a regulated monopoly or an unregulated monopoly.  Naturally, corporations shun regulations, so they desire strongly to be classified as Title I unless subsides are available then they like Title II.

In light of Verizon‘s (and others) desire to dump the old copper PSTN network in favor of fiber to premises (AKA FiOS) do they not also become Title II providers by default?  VoIP telephone service, whether through FiOS or the cable company is becoming the default in many places.  The Internet, like other utility services has gone beyond “informational” classification to the needed and necessary to do business category.

Cable and other wired networks, which own “natural monopolies” of broadband facilities either need to be regulated as such or loose their monopoly status through unregulated competition.  There are other ways to deliver broadband internet to business and residential customers.

The Shively 6710 Antenna

Shively 6710-1 FM antenna

Shively 6710-1 FM antenna

Perhaps that is one Shively Antenna that you haven’t heard of. They were an odd-ball combination of a horizontally polarized antenna with an adjustable vertical element. This design allowed the station to adjust the ratio of horizontal to vertical power from a range of 1:1 to about 4:1 (H:V).  Why would this be a desirable feature?

Back in the early days of FM broadcasting, almost all stations had horizontally polarized antennas.  This system worked remarkably well, stations could broadcast at moderate power levels over fairly long, line of sight (or mostly line of sight) paths.  Most FM receivers were stationary units installed in people’s homes often with outdoor antennas.

It was not until the late 1960′s and early 1970′s that FM radio receivers became a stock option in most low and mid cost automobiles.  It was then that a slight problem with FM broadcasting was discovered;  car antennas are vertically polarized.  People driving around in their new machines found that the FM reception was not all that great.  Stations began adding a vertical component to their signal to help improve the mobile reception situation.

I found this Shively Brochure in a file cabinet drawer at the WFLY transmitter site.  This model antenna was ordered and installed by that station in 1970.  It had a 3:1 horizontal to vertical ratio.  Why not install a fully circularly polarized antenna?  Because often that necessitated installing a new, more powerful transmitter.   Every watt of power take from the horizontal plane and added to the vertical plane reduced the ERP by that much and had to be made up with more transmitter power output.  Often times, the ratio of H:V power would be adjusted to take up whatever headroom there was in the transmitter and the station would run that way until the next transmitter replacement cycle.

It is a strange looking piece of kit, a sort of make do until the situation could be fully rectified.  I think this antenna was in service until 1986 or 87 when it was replaced with a circularly polarized ERI.