March 2012
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Generators and mice

Never a good mix, unfortunately, it usually turns out bad for the mice and sometimes the equipment.  This is a Onan GGMA 20 KW propane generator installed in a rural area, not that the location matters that much.  Mice will find what they perceive as a safe secure spot to hold up for the winter.

Onan GGMA20 propane generator

Onan GGMA20 propane generator

Unfortunately, the mice decided that the generator cooling fan was a good place to make a nest.  It probably was until the generator started, then the mice had a quick lesson in centripetal force.

Mice and generator

Mice and generator

This will require some additional maintenance in the spring time when I change to oil.  By that time, the carcases should be mostly dried out and easier to deal with.

Onan generator mice

Onan generator mice

The mice are generally a nuisance, getting into ATU’s, transmitters, electrical panels, spare parts boxes, etc.  Once in place, they begin to bread and reproduce.  The gestational period for a mouse is 21 days, which means populations rapidly increase creating further problems. If left alone, mice will chew through electrical insulation, control wires, cardboard boxes, packing material and so on.  They tend to carry diseases like hantavirus and bubonic plague.

I don’t usually agree to using poison to get rid of pests, it tends to linger in the environment and accumulate up the food chain.  However, judicious use of some type of poison is usually the only way to effectively get rid of a mouse infestation.

Wherever possible, make sure that all openings and holes into equipment and buildings are sealed up.  Do not kill snakes and other predators, who will assist in keeping the mice in check.  Employ traps and wear gloves when removing dead mice and mouse parts.  Beware of fleas.

WNAW North Adams

Originally signed on as WMNB in 1947, it is a Class C AM station on 1230 KHz, one of thousands in the country. Initially, it had a power of 250 watts, upgrading at various times to its current power of 1,000 watts.

WNAW-WUPE-FM, North Adams, Ma circa 2012

WNAW-WUPE-FM, North Adams, Ma circa 2012

What is different about this station is the studio building. It is located in it’s original place on Curran Highway on the south side of North Adams. The studio is a late Art deco design, complete with small glass atrium in the lobby.  Like many older radio stations, this installation was built on a raised floor.  The walls and doors are all well constructed for maximum sound attenuation.  The doors are large, heavy and solid wood.

WNAW news room, formerly the performance studio

WNAW news room, formerly the performance studio

Inside, the original studios are laid out with a control room, a broadcast studio and a live performance room.  At one time, the live performance room had a grand piano.  Several times per week, live music shows were broadcast on the station.  There was a large news room, a big corner office for the General Manager and sales managers.

WNAW studio monitor speakers

WNAW studio monitor speakers

WNAW studio, looking into the control room.  Back in the day, the announcer, who’s only concern was announcing, worked in a separate studio from the engineer on duty, who worked console in the control room.  The audio level limiting consisted of turning down the level on the console if the announcer started speaking loudly.  They often communicated with each other with hand signs through the windows.

WNAW lobby

WNAW lobby

At the time that WMNB was signed on, the Adams/North Adams Massachusetts area was in the heart of the north east manufacturing belt.  Sprauge had a capacitor plant in Adams, GE was making plastics in Pittsfield, There where many textile mills still in operation and so on.  The population was predominantly working middle class.

WNAW control room console

WNAW control room console

Obviously, the console has been changed since those days.  The current console is a Audio Arts R-60.  This serves as the control room for WNAW and WUPE-FM.  The programming for WUPE-FM comes from Pittsfield on a T-1 line.  From here, it is relayed to the transmitter site on a 950 MHz STL.   WNAW transmitter is located about 2/10 of a mile south of the studio building on Curran Highway.  It consists of a skirted self supporting tower with a Gates 1 solid state transmitter.

WNAW-WUPE-FM equipment racks

WNAW-WUPE-FM equipment racks

Equipment racks containing the T-1 equipment, modulation monitors and STLs.  Note the very old Moseley TRC-15 remote controls.  We have been unwiring these at the transmitter sites and disconnecting the TELCO lines.  The transmitter sites now have Sine Systems dial up remote controls.

In 1961, WMNB-FM (now WUPE-FM) signed on the air from a tower north east of down town, off of Mohawk Trail (MA route 2).  It broadcast on 100.1 MHz with an ERP of 1,000 watts using a Gates FM1B transmitter.

WNAW continues on today as a community based radio station and is well liked and supported.

The Harris Z6HD transmitter

These transmitters are good.   They seem to behave in a mostly normal manner, having a few quirks now and then. This particular unit is installed at WFAS-FM in White Plains NY.

Harrsi Z6HD transmitter, WFAS-FM, White Plains, NY

Harrsi Z6HD transmitter, WFAS-FM, White Plains, NY

I believe the reason for the installation was for the HD Radio® that was in it.  The Deathstar HD Radio® exciter is in the next rack over.  No further comment needed.

On this day, the transmitter had given up, throwing a main fan fault.  The fan (blower) motor had been replaced in the last six months (on a transmitter that is only five years old), so it was not that.  As it turns out, the stock fuses; 10 amp, slow blow, were just a little bit underrated for the job.  Harris released a service bulletin a few years ago calling for 15 amp slow blow fuses as replacement.  In any case, it was an easy fix and now there is a box of 15 amp slow blow fuses in the transmitter next to the fuse holders.

Harris Z6HD transmitter front RF modules

Harris Z6HD transmitter front RF modules

The modules are accessible by the front and rear of the transmitter.  These doors can be opened with the unit is on the air, since all of the high voltage is in the bottom of the transmitter where the blower is located.

Module in the middle is the IPA.  Each module has two RF amps, each RF amp has two devices (BLF-177).  The devices are field replaceable, however, on the HD models, one has to make sure that the amplifiers are still linear.  On the non-HD models (Z6CD), this is not a problem at all.  Shorted MOSFETS will be noted by a fault of one entire power supply.  Removing the bad RF module will allow the transmitter to run at somewhat reduced power.  Finding the bad module may take a bit of trial and error.

Harris Z6HD transmitter back

Harris Z6HD transmitter back

The back of the transmitter has the directional coupler, low pass filter,access to the back of the analog exciter, controller and remote control connection points.

The power supply in the bottom of the transmitter has multiple taps, each on with its own fuse.  These can be a bit of a chore to work on.  There is also a ribbon cable that goes from the controller to the power supply board.  This is directly in the path of the cooling fan and can flop around causing the conductors in the cable to break.  The result is the power supply may not come on, or may show an unbalanced power supply condition (in the case of a three phase transmitter).  Very difficult to diagnose.

Harris Z6HD transmitter, on air, WFAS-FM, White Plains, NY

Harris Z6HD transmitter, on air, WFAS-FM, White Plains, NY

Here it is, running again.

Leave Rush Alone

The man is an instigator, a pot stirrer, and a knave.  I find his show boring, predicable, uninformative and uninspired, a three hour long recitation of Republican talking points.  I agree with almost nothing he says.

That being said, the reaction to the latest Rush Limbaugh shock jock provocation seems irrational.   Gloria Allred, an attorney herself, declared he should be arrested.  Really?  You should know better than that, after all that fancy law schoolin’ and such.  The Los Angles City Council passed a resolution banning intolerable radio speech.  Called “largely symbolic” which is double speak, one wonders what symbols we should associate with such a measure.

The reason for the first amendment to the constitution is to prevent the very slippery slope of banned speech and censorship.

It is time to reacquaint people with some of the basic controls on a radio.  The first is called the “tuning knob” or on modern radios, the “seek” button.  You can press (or turn) this when you are not hearing something to your liking.  The other control know on the radio is the “volume” knob.  This can be used to turn the radio volume down or off.

As far as Rush Limbaugh is concerned, if enough people use the aformentioned radio controls, he will eventually end up on XM/Sirius, where all big DJ’s go to fade away, with the likes of Howard Stern and Oppie and Anthony.  It would be far better to allow the market to decide Rush Limbaugh’s fate, than to try and wage some type of questionable legal war on free speech.

The FCC LPFM plan

FCC moves ahead on a couple of different fronts in the LPFM battle.  Cliff notes version:

  1. The 2003 translator filing window question.  The FCC has more or less stuck with it’s plan to keep a minimum number LPFM channels available in the top 150 markets.  This also includes a 50 application limit for the country and no more than one application per market per applicant.  Where conflicts occur, translator applicants get the chance to demonstrate how their application would not preclude LPFM opportunities.
  2. Modifies (eventually eliminates) the May 1, 2009 cut of date for cross service (AM to FM) translators.
  3. The establishment of new LPFM allocations under the criteria of disregarding the third adjacent channel contours.
  4. More stringent requirements for local programming and ownership, especially as a determining factor for mutual LPFM applications.
  5. Allows LPFM stations to own translators.
  6. New class LPFM is established; the LP250.  The 250 watt LPFM stations are designed mainly for areas outside of top fifty markets or for previously licensed LP-100 stations that want to upgrade provided the minimum separation contours are met with existing stations.

The FCC has included the proposed rule changes as appendix A of FCC 12-28.  Standard FCC comment and reply windows apply.

Looks like things are moving along pretty fast.  Others have speculated at a filing window sometime later this year, I’ll not do that.

Lightning season

Here in the northeast, there are seasonal various in the types of weather phenomena encountered.  Blizzards in the winter, severe thunderstorms and the occasional tornado in the summer, at least that is the way it normally happens.  This year, we have already had two thunderstorms and a stretch of unusually warm weather.  My highly advanced personal weather prognostication technique consists of looking at trends, and the trend thus far this year is warmer with more storms.

Weather Radar, thunderstorm line

Weather Radar, thunderstorm line

When the weather RADAR looks like this, it is too late.

To that end, it is time to go around and check all of the grounding and lightning suppression methods at various transmitter sites and studios.  I would rather spend a few minutes extra now than get called out in the middle of the night for an off air emergency related to a lightning strike.

Proper grounding of all equipment, RF cables and electrical service entrances are the minimum standard for transmitter sites.  Proper grounding means a common point grounding system connected to one ground potential.

To that end, all coaxial cables that enter the building need to have their outer shields bonded to the site grounding system at the base of the tower and the entrance of the building.  With an FM station where the antenna is mounted at the top of a tall tower, the coaxial cable outer jacket acts as in insulator along the length of the tower.  A lightning strike on the tower will induce a very high potential on the outer conductor of an ungrounded transmission line.  After entering the building, the lightning surge will find the next path to ground, which will likely be a coax switch or the transmitter cabinet.  Neither of those two outcomes is desired.

Thus, it was time to ground the transmission lines at WRKI, the FM transmitter we moved last January.

3 inch coaxial cable grounding kit

3 inch coaxial cable grounding kit

Fortunately, Andrew, Cablewave, Dielectric and others make grounding kits for various size coaxial cables. They are very easy to apply and make a solid connection between the outer conductor and the site ground.

3 inch coaxial cable grounding kit

3 inch coaxial cable grounding kit

The kit contains a copper band bonded to a ground wire, stainless steel clamp, water proofing, tape and a pair of bolts.

3 inch coaxial cable properly grounded

3 inch coaxial cable properly grounded

The concept of transmitter site grounding is pretty simple and inexpensive to implement.  Thus, it is surprising to me how many transmitter sites, especially older sites, that do not have adequate grounding.  That is an accident waiting to happen.

For more on transmitter site grounding, check Nautel’s publication (.pdf) “Recommendations for Transmitter Site Preparation.”

GPS Jamming devices: FCC says No!

The FCC has become concerned about Jamming devices for Cellphones, GPS and WiFi.  So much so, they have released Enforcement Advisory No. 2012-02, which specifies fines in excess of $100,000 per incident.

The advisory states:

In recent days, there have been various press reports about commuters using cell phone jammers to create a “quiet zone” on buses or trains. We caution consumers that it is against the law to use a cell or GPS jammer or any other type of device that blocks, jams or interferes with authorized communications, as well as to import, advertise, sell, or ship such a device. The FCC Enforcement Bureau has a zero tolerance policy in this area and will take aggressive action against violators.

I have two three thoughts:

  1. GPS jammers are increasingly being employed by those who are concerned about their privacy.  That set of people can range from truckers who don’t what their bosses to know every aspect of their journey, citizens concerned about GPS tracking devices on their vehicles, or ordinary people who don’t want the phone company tracking their every move via GPS enabled cellphones.
  2. If only the FCC were as diligent and judicious in pursuit of other interference issues in the radio frequency spectrum.  A few that immediately spring to mind; IBOC to analog adjacent channels, broadband over power line, electrical noise on the medium wave band, illegal 2 way radios on RPU frequencies, etc.  Of course, there is no money in those issues.
  3. Wasn’t the FCC about to allow Lightsquared to install high powered 4G data transmitters all over the place, thus jamming GPS anyway?  I know they nixed that plan after the general uproar over loss of GPS by things like aircraft in flight, etc.

It remains to be seen how, exactly the FCC is going to find things like this:

Small GPS jammer

Small GPS jammer

Hypothetically speaking, in a mobile operating environment while traveling down the interstate at 70 MPH with thousands of other vehicles, it would be the proverbial search for a needle in a haystack.  This would be especially true for a GPS only jamming device, which would require a very small amount of power to jam the weak satellite signals.  It presents an interesting problem for the cash strapped enforcement bureau.

Not all jamming devices are this small, however.  After doing a Google search for GPS jamming devices I notice that some of them are great big honking things, with heatsinks and fans, capable of generating large signals on every cellphone, WiFi, 3/4G and GPS frequency.   Those larger jamming devices would be very easy to locate and disable.

Perhaps if the technology wasn’t so pervasive and readily abused by certain corporate and government entities, the desire to jam it wouldn’t exist.

This is just wrong

My apologies to all those who think that translators are more than relay points, a way to fill in coverage from the main FM station they are relaying.  They are not.  I read this bit of information on this morning:

Townsquare Media bought the Albany-licensed translator from Bud Williamson’s Digital Radio Broadcasting last year for $245,000, and the signs were that it would go soft AC as “Sunny.”

The translator is going on the air as a soft AC?  WHAT?  Further down in the article it goes on to say that the translator will actually be relaying an HD-2 channel from WQSH, 105.7, a station 22 miles away.  Oh, well, that makes it okay, right?

Lets start with FCC 74.1231(a), which states:

FM translators provide a means whereby the signals of AM or FM broadcast stations may be retransmitted to areas in which direct reception of such AM or FM broadcast stations is unsatisfactory due to distance or intervening terrain barriers, and a means for AM Class D stations to continue operating at night

Notice it says “FM” or “AM.”  Since we all know that FM stands for Frequency Modulation and AM stands for Amplitude Modulation, where does that leave HD Radio®, which is neither.  As a point of technicality, HD radio uses a OFDM modulation scheme.  It may seem stupid or simple to point that out, but that is the way the rules are written and HD Radio® is not AM or FM no matter which frequency band it is using.

The second point is that translators are not supposed to originate local programming.  Again, this is a simple work around.  By putting the programming on some HD2 channel from somewhere, it is legal.  They are not even trying to hide the fact that the translator is the main market signal, calling the station “Hot 99.1,” which is the frequency of W256BU, not the so called originating station, 105.7.

Blatant, blatant, blatant disregard for the intent of translator regulations and ownership regulations.  This is something that the FCC can address in its broadcast ownership review, but of course, they won’t.  This whole, wink, wink, nod, nod business is getting a little bit difficult to stomach.  The question is what can be done about it?

FCC to review Broadcast Media Ownership, again.

In the never ending drive to have one gigantic mega corporation own everything, the FCC will be reviewing the current set of regulations to make sure that they are in line with those goals.  It is very interesting what is not being said about Mitt Romney, Rush Limbaugh, Premere Radio networks, Clear Channel Communications, Bain Capital, the Republican party and the upcoming election.

The usual suspects are coming out for and against any change.

Does anyone else not see this?

I will let George take this one:

It may indeed be too late to do anything about the broadcast media ownership rules, as the lid came off Pandora’s box in 1996. Now is the time, however, to be ever vigilant against attempted censorship of New Media.




Why be a Broadcast Engineer?

That question was posed to me this afternoon by a coworker.  It is, indeed, a good question.  Certainly, broadcast engineering is more of a vocation than a career, especially where it concerns radio stations.  Why would anyone work for low wages, long hours, little or no recognition, 24/7 on call, and or unappreciative management.

Further, in this risk adverse, zero defect, micromanaged environment, what is the upside to being a radio, RF or broadcast engineer?

I suppose one would have to have some appreciation for history.  One of the reasons I cover radio history here or certain historical events is that  without knowing the roots of radio, one would be hard pressed to find today’s version of radio broadcasting even remotely interesting.  Understanding the before there was an internet, web streaming, Spotify, Youtube, Sirius/XM, television, cellular telephones, 3G, 4G, and so on, radio was mass media.  Radio was people driven, people oriented, not an automation computer programmed from afar.  People tuned in for the music but also the personality and the personal connection.

Growing up in the late sixties and seventies, radio was my link to the outside world.  As a young boy living in rural upstate New York, my mostly agricultural surroundings seemed a bit provincial.  Through radio, I was able to listen to the clear channel stations from New York City, Chicago, Detroit, Nashville, Charlotte, Pittsburgh, Washington DC, Cincinnati, etc.  The street that I grew up on did not get cable TV until 1980, prior to that, the roof top antenna received exactly two channels, when it wasn’t blown over by a storm.  The black and white TV was often broken, sometimes for over a year.  It was of not great consequence however, when nightly under my pillow, the battery powered transistor radio was employed until midnight or later.

When I got older, shortwave radio kits were built and listened to.

Through that medium, I learned about life outside of my small town.

Author, sitting in front of Atwater-Kent Model 20 regenerative receiver

Author, sitting in front of Atwater-Kent Model 20 regenerative receiver

The upside is being a part of something that can still be great, although those stations are getting harder and harder to find.  Still, there is a certain pride to a job well done, a clean transmitter room, a well tuned machine working into a properly tuned antenna.  Does anyone even appreciate that anymore?  I do.  Lou Dickey, John Dickey, Bob Pittman, Leslie Moonves, and other CEO’s may not care that transmitter site is clean and well kept.  They may, in fact question it as a waste of salary.   I appreciate it. Fellow engineers will appreciate it, too.

Starting a transmitter, especially a high powered tube transmitter, is a joy all it’s own.  Nothing against Nautel, they make fine transmitters, however, when pressing the on button, the outcome is almost assured: The transmitter will turn on.  Not so with certain tube type transmitters.  Pressing the plate on button for one of those can have many different outcomes.  There is certain thrill when it all works right, the first time.  There is a certain pride driving away from a transmitter site, listening to the radio and knowing; I caused that to happen.


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 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!