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CHU: Time nor tide waits for no man

CHU is a HF time signal station operated by the National Research Council of Canada. It operates 24/7 and announces the hour and minute each minute of every day on frequencies 3,330, 7,850 and 14,670 KHz. This is the Canadian counter part to WWV and WWVH.  In the strictest sense of the term, it is a broadcasting station, although many would also classify it as an HF utility station as well.  Many countries had HF time signal radio stations at one time, but there are fewer now.  Back in the day before GPS, these time signals were critically important to anyone needing coordinated event timing.  We used the carrier frequency from WWVH as our frequency standard for test equipment.  WWV and WWVH also transmitted a very accurate 1 KHz tone for the same purpose.   According to the CHU web site:

Normally CHU’s emission times are accurate to 10-4 s, with carrier frequency accuracy of 5×10-12, compared to NRC’s primary clocks, which are usually within 10 microseconds and 1×10-13 compared to UTC.

Additionally, every minute between 31 and 39 seconds, CHU broadcasts FSK time code with a Bell 103 standard (2225 Hz mark, 2025 Hz space) at 300 bits/second (IRIG time code).  This could be used as a backup for GPS time clocks on automation systems, if GPS were to fail for some reason. One would have to write a little software program to decode the hex output and reset the computer clock once per minute accordingly.  That should not be too hard.  LINUX information and software can be found here.  More on CHU time code here.

CHU Ottawa, Ontario, Canada

CHU Ottawa, Ontario, Canada

In my location 3,330 KHz is audible 24/7.  That signal is transmitted with a carrier power of 3 KW into a non-directional vertical dipole antenna as is 14,670 KHz.  The 7,850 KHz signal is transmitted with a carrier power of 10 KW into the same type antenna.

Canadian Time Signal station CHU, aerial view

Canadian Time Signal station CHU, aerial view

There is some discussion of adding an additional time station transmitter in western Canada and of changing the modulation from AM to DRM or at least adding some type of DRM service.

Happy Thanksgiving Everyone

Update2: Repost from last year.

Alice’s Restaurant is a Thanksgiving tradition at most radio stations I worked at over the years, normally played around 12 noon or so.

Courtesy of YouTube, here is Arlo himself telling the story with some clips from the movie of the same name to go along with it:

A few years go some other guy, Adam something or other, that tried cash in with a Thanksgiving Song of his own, which sounds an awful lot like the Chanukah song he also did.

Update1: Jeez, there is apparently a Wikipedia article about everything.  Here is teh background on Alice’s Rest-a-raunt.

For those familiar with WKRP, here is the Turkey Drop:

Happy Thanksgiving!

Occupy Bandwidth

Or rather occupied bandwidth.  During a recent Alternative Inspection of an FM station, there was some question as to the accuracy of the modulation monitor.  Truth be told, a modulation monitor is no longer required at a radio station, so long as the station ensures that they comply with relevant FCC regulations for their service.  Many modulation monitors continue on, however, as air monitor receivers.

That is all well and good, however,  many modulation monitors are notoriously inaccurate and tend to the overly sensitive side of the equation.  If used when setting the modulation levels, this can lead to under modulation, which, as we all know leads to disaster, destruction and bad ratings….  Because the volume knob on every radio in the entire metro, Total Survey Area (TSA), or even the whole country has been broken off and listeners are unable to compensate for the low audio levels from an under modulated FM transmitter.

But anyway.

FCC 73.1560 gives the maximum FM deviation as +/- 75 KHz from the carrier, with some allowance for SCA injection levels, up to +/- 78 KHz.  This is the definition of 100 percent modulation of an FM carrier.  Thus the entire occupied bandwidth is 150 KHz, leaving a guard band of 50 KHz between signals. That is, unless IBOC is employed, then the guard band is -100 KHz which is good science no matter how one looks at it.  On a spectrum analyzer, it looks something like this:

Occupied bandwidth of analog FM broadcast transmitter

Occupied bandwidth of analog FM broadcast transmitter

This shows that the 5 second average occupied bandwidth of 90 percent of the transmitted energy is within 153 KHz, which is slightly high but within the margin of error of the measurement device.  The vertical lines represent the -10 dB signal level as referenced to the carrier.  Thus this station is in compliance with FCC rules regarding modulation in spite of the face that the analog modulation monitor shows it being 10-20 percent over.   Had it actually been 110 percent, the occupied bandwidth would have been 165 KHz and 120 percent would have read 180 KHz.

Thus, before buying the latest squash-o-matic FM processor and setting it for full tilt boogy, a good engineer may want to check the occupied bandwidth with something other than the old analog FM modulation monitor in the rack.

Shortwave Radio picks

Winradio G303i software defined radio, 7490 KHz WBCQ

Winradio G303i software defined radio, 7490 KHz WBCQ

I enjoy listening to radio, however, there seems to be a dearth of good programming on the conventional frequencies.  Somehow, personality-less robo programmed hit music and right wing talk radio just doesn’t seem to cut it anymore.  Thus, I have taken to listening to the shortwaves.  Truth be told, the availability of good programming is dwindling there as well, but good things can still be found.  Here is my list of interesting and or entertaining programs found on the shortwave:

  1. Radio Australia International – 9580 KHz mornings from 6-9am EST (11-1400 UTC).  There are a variety of good programs on this station including Asia-Pacific, Saturday Night Country and others.  Good to listen to with my morning cup of coffee.
  2. WBCQ – Several good selections here including Alan Weiner World Wide (Fridays 8-9pm), World of Radio (Glen Hauser, Thursdays 5:30-6pm), Marion’s Attic (Sunday 5-6pm), Le Show (Harry Shearer, Sundays 7-8pm) Amos n’ Andy (Tuesdays 5-5:30pm).  New 41 Meter Frequency 7490 KHz is clearer than previous frequency.  5110 KHz is hit or miss in this location, however Area 51 is worth a listen (Saturdays and Sundays 7-11pm) if reception is good.  Check their schedule on line as program time change.
  3. WWCR – 12160 KHz 12-3pm EST (17-2000 UTC) Alex Jones, entertaining if not a bit over the top, tends to rant, makes some good points when calm.  Other programs like World Wide Country Radio, The Pat Boone Show, etc are available at various times on various frequencies.
  4. CBC North – 9625 KHz Continuous Sackville feed of CBC Radio One, mostly in English, occasionally in Inuktitut or French.  Good for news from the Great White up.
  5. CFRX – 6070 KHz shortwave feed of News/Talk CFRB Toronto.  Conservative news talk programming Canadian style, some good trivia games and whatnot.
  6. WEWN – 15610 KHz Catholic Mass (8-9am Sundays) although lately they have been re-runs, which is goddamned annoying.

There are others from overseas, but many of the English broadcasting services are being scaled back or eliminated.  A few broadcasts that one is sure to come across when tuning around; The Voice of Russia (bland, predicable, promos sound like they are recorded in the bathroom), Radio Romania (meh), China Radio International (100% propaganda), Radio Havana, Cuba (campy, mildly entertaining in an absurd way), etc.

Pirate Shortwave broadcasters roam around in the 6890-6970 KHz range.  They are irregular in schedule, low power and often contain an obscure dialog or some selection of 80’s hair band music.  Still, if one has some time, they can be entertaining too.

A good source of information on shortwave broadcasts is Short-wave.info which has a pretty accurate searchable database and a great feature called “Find out what stations are broadcasting on a frequency of (fill in frequency) Now.”  That is very helpful for figuring out what a station is without waiting for station ID or if broadcasting in another language.

With winter coming and the sun spot cycle on the upswing, the HF bands should be open for business.

The 80 Amp Circuit Breaker

Just because I can, here are a few pictures of the inside of a rather expensive 80 amp DC rated circuit breaker:

80 amp DC rated circuit breaker open

80 amp DC rated circuit breaker open

What is the difference between a DC rated breaker and an AC rated breaker? Good question. Because DC is, well DC, the current is continuous. Once an arc is struck, greater separation is needed between conductors to extinguish the arc.  Using an AC breaker in a DC application can lead to an internal arc and fire.  That would be a bad outcome.

Just how did the insides get exposed, one might ask? Well, there I was working on a solar installation with said breaker placed on a horizontal surface waiting for installation when somehow it was knocked to the floor, creating a large crack in the side of it.  Angry I was because this thing set me back some fifty dollars.

80 amp DC rated circuit breaker closed

80 amp DC rated circuit breaker closed

This picture shows the breaker closed, the contacts are still under cover to the left of the exposed parts. What is cool is one can get a good idea of how a circuit breaker works.  As the current flow increases, the magnetic field around the coil increases.  When it reaches the trip point the small steel piece is pulled down, causing the mechanical assembly to unlock and open the contacts.

Old tech stuff that is taken for granted, probably has saved millions of lives since electrical use became widespread.

The CCA AM1000D

Still in use as the main transmitter after 42 years at WCKL 560 KHz, Catskill, NY.

CCA AM1000D transmitter, WCKL Catskill, NY

CCA AM1000D transmitter, WCKL Catskill, NY

The last seven years or so, it has not had much use, the station being caught in some strange LMA with Clear Channel, then sold to the Black United Fund of NY something or another. They basically had it dark, turning it on for a few days each year to as not to loose their license.  Finally, they LMA’d it to Family Broadcasting (not to be confused with Family Radio).  There are rumors of a sale, but it remains to be seen.

They have been broadcasting an eclectic, free form programming style which appears to be the work of mostly volunteers.

The station was first licensed in 1970, thus this is the original transmitter:

CCA AM 1000D name plate, WCKL Catskill, NY

CCA AM 1000D name plate, WCKL Catskill, NY

Towers are 446 feet tall, which works out to 90 degrees at 560 KHz.

WCKL 560 KHz antenna array

WCKL 560 KHz antenna array

The station is licensed to Catskill, but the transmitter site is located in Hudson, across the river. With the current ownership situation in flux, I would characterize the operation as “tenuous.”

The transmitter itself is a pretty simple high level modulation tube type transmitter.  It uses 4-400 tubes, like the RCA-BT1AR transmitters and is build around a similar design, which makes sense as they were designed and built by former RCA engineers.  One of the CCA principles, Bernie Wise, still makes Energy Onix transmitters about 10 miles away in Valatie, NY.

Parts are fairly generic and still available.  Things like the modulation transformer may be harder to come by, however, Goodrich Electronics, Harbach Electronics, Energy Onix and others will be able to steer one in the right direction. I’d put up a schematic if I could find one.

I find these older tube type transmitters often sing with modulation, especially the higher frequencies.  That sound and the soft sound of the blower moving air is the sound of radio, at least to me.

Trends in Terrestrial Broadcasting

I thought I’d take a few moment to explore the current trends and development in Terrestrial Broadcasting, AKA AM, FM, TV and Shortwave.

Clear Channel Communications RIFs employees

We are all aware of the “reduction in force” or RIF (a term used by the US armed forces in the mid 1990’s), as it is called by Clear Channel Broadcasting.  One could also call it the iUnheartEmployees program.  Small and medium market stations bore the brunt of these reductions, although major markets were not immune either.  According to Clear Channel, this will  “deliver a much better product to listeners than we have in the past.”  Also, they plan to “generate higher ratings for our advertisers and marketing partners and give our best people bigger roles.”  Of course, the definition of “much better product,” is subjective and depends on one’s point of view.

In addition to that, the Brand Management Teams indicate the inception of nationwide network radio or at least nationwide radio format standardization, which is almost the same thing.  This trend will further eliminate the need for local program directors, local news, local anything.  With greater commitments to the iHeartRadio and the hiring of Bob Pittman as CEO, expect more in the way of new media, internet distribution and so on, possibly at the expense of terrestrial radio transmission.

Clear Channel owns approximately 850 of the nation’s 11,293 commercial AM and FM radio stations.

Cumulus-Citadel merger

We are also aware of the Cumulus-Citadel deal, which leaves one less large company on the field and greatly improves Cumulus’s major market presence.  In addition to several radio stations, Cumulus also acquires what used to be ABC radio networks and satellite distribution system.  Prior to the merger, Citadel had several satellite radio formats ranging from Top 40/CHR to 24/7 Comedy.  There is no word on how the merger will change those formats and what Cumulus plans to do with them.  I would speculate that similar to Clear Channel, national type formats are in the works for Cumulus as well.

Cumulus Media owns approximately 570 of the nation’s commercial AM and FM radio stations.

National Public Radio NPR

The third large group of radio stations is more like a collective than commonly owned group.  Stations or groups of stations are owned by regional group owners and form mini-networks, for example, Northeast Public Radio.  The flagship station for Northeast Public Radio is WAMC, however, they own 11 radio stations and 12 translators.  This is fairly typical of NPR affiliates.

NPR stations act in concert with the CPB (Corporation for Public Broadcasting) and NPR to form a powerful media presence.  Most stations carry some local programming, however, NPR staples such as Morning Edition, All Things Considered and Weekend Edition are almost universally heard on every NPR affiliate.

Technically speaking, NPR stations make up the single biggest block of HD Radio users, almost all of which where licensed and installed under by grants from the CPB.  NPR labs has done extensive work testing and attempting to improve HD Radio, taking over for iBquity’s own in house engineers.  NPR is also exploring ways to use new media distribution networks, moving towards a more IP based distribution model over terrestrial radio.

NPR is funded by member stations, the CPB and by corporate sponsorships.  The largest ever was from the estate of Joan Krock (McDonalds Corporation), which lead to the Steve Inskeep/Morning Edition story about how great it was to work at McDonalds.  There is/have been several efforts to defund the CPB in recent years.  With the economy going the way it is and all, the congressional moves to defund may win, which would be a crippling blow to NPR.

NPR affiliates number approximately 850 of the 3,572 non-commercial FM radio stations and about 50 AM stations in the US.

Other broadcast groups such as CBS, Entercom, Emmis, etc

Those companies will likely follow whatever Clear Channel and Cumulus are doing, as those companies are driving marketplace trends and competition, or lack thereof.

Voice of America, US government

In a somewhat surprising development, the Broadcasting Board of Governors, who oversees the operations of the Voice of America would like to repeal some parts (.pdf) of the 1948 Smith-Mundt act, which prohibits them from broadcasting domestically.  Does this mean that the VOA will become a government broadcaster like the BBC and CBC?  I don’t rightly know.  The BBG is also proposing to greatly curtail HF (AKA Shortwave) transmissions, favoring a combination of Satellite to FM and IP network delivery methods.  The BBG is also proposing defederalizing the VOA (AKA privatization).  Perhaps one of the current large broadcasters, e.g. Clear Channel or Cumulus will be interested in purchasing the VOA brand name.

With the repeal of the Smith-Mundt act, does this open the door for some form of domestic shortwave service?  I have commented several times on the ability of HF radio to cover large distances with moderate power levels.  The 1,000 watt non-directional CFRX on 6070 KHz is good example of this.  Most hours of the day, it is listenable at my location, some 300 miles distant from the transmitter.  I enjoy listening to Toronto news and talk as much as any other.  Lower frequencies and moderate power levels would be an interesting experiment.

What does the future hold for broadcast technical people?

RF vs IP distribution

RF vs IP distribution

All of this points to more consolidation of engineering staffs, centralized NOCs (Network Operations Centers) and more emphasis on computer/IT skill sets verses the legacy AM/FM transmitter and analog audio skill sets most broadcast engineers have.  The old days of the RF guru are coming to a close.

Most new transmitters have some sort of web interface, which allows complete remote monitoring and supervision.  If a transmitter does not have that, remote control units can be web enabled.  These transmitters are modular, with the modules being removed and returned to the factory for repair.  That innovation greatly reduces the amount of training and experience required to maintain transmitters, almost anyone can remove a module and ship it somewhere.  That, in turn, leads to a more consolidated technical staff with field engineers being dispatched to specific sites to take care of outages as needed, which is the model that the cellphone companies and wireless service providers use.

Further, as evidenced in this discussion on the radio-info board, many of the older engineers are becoming tired of underfunded, neglected physical plants.  The idea that a contract engineer is someone you call only when you go off the air has been around for quite some time.  As time goes on, fewer and fewer are willing to accept that type of work.

The future looks like radio station technical staffs will be mostly computer related technicians and engineers that take care of problems remotely from a NOC.  If a physical presence is needed, a field technician can be dispatched.  These people will most likely be contractors.

Smaller groups and the mom and pops that are left will have to get on board with the reality that fewer and fewer contractors will be willing or able to trouble shoot a tube amplifier and replace there transmitters with newer solid state units.  Manufacturers, if they are on the ball, will want to offer some type of monitoring service for those type customers, again, dispatching a field technician as needed to effect repairs.

Either way, computer and networking skills are a good thing to have and are transportable to other sectors, should one find oneself an unemployed broadcast engineer.

National EAS test results

Mixed, at least in my neck of the woods.  I was stationed at a LP-1 station which was monitoring a PEP station directly.  On my end, the test went fine without intervention. Please excuse the cellphone video, I am used to my good camera, which I left at home.

Many others in the New York area had problems.  Stations with newer SAGE (Blue front) CAP capable EAS ENDECS had issues, even the ones that were also monitoring the PEP stations directly.

Many of those stations broadcast the header tones and about 10 seconds of audio.  The audio abruptly stops and is followed by twenty seconds of dead air followed by the EOM.  I can speculate that the SAGE EAS units should be checked for proper configuration and be tested back to back while receiving duplicate messages from different sources spaced apart by ten seconds.

Several stations downstream from the LP-1 stations did not receive anything at all.  Others received the alert tones but no audio, some had high levels of background noise, thirty seconds of static, audio cut off, etc.  All in all, most would look at this and say “Thank God it wasn’t a real emergency.”  Silver lining: For all those that are concerned that the federal government will attempt to diabolically take over the entire broadcast spectrum and say evil things; Doh! foiled again.

Tower take down video

Since the inception of youtube, I’ve watched hundreds of these tower collapse videos. I don’t know why, it interests me. This video is of the Coast Guard LORAN C tower in Port Clarence, Alaska. For what it’s worth, Port Clarence looks like a forlorn place, I am inclined to think my duty on Guam was rather nice in comparison.

This was filmed from six separate camera locations, including one at the base. It demonstrates how most towers fall within 1/3 of their constructed height. In this demolition, all three guy points are cut at the same time, removing the equalizing forces simultaneously. This would be the same situation as a catastrophic failure of a load bearing tower member.

The best parts of this video are the camera view of the tower base, around 1:04-1:19 and the side view where the camera almost gets hit by a tower section, 2:02-2:13.

I love physics.

Corporate controlled media?

I don’t know, what do you think (starts about 1:10)?

It is utterly amazing that all those news copy writers came up with the same story lead in, across multiple networks and cities.  This is one of those canned news items that stations pick up when they don’t have other news to fill a segment.  Seems to be a slow news day.

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

Free counters!