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The Gates Air FAX-10

This is the first one of these transmitters that I have installed. This particular unit is analog only, but there is lots of room left over for an HD exciter, if need be.

GatesAir Flexiva FAX-10, 10.000 watt FM transmitter

GatesAir Flexiva FAX-10, 10.000 watt FM transmitter

The size of a 10 KW FM transmitter these days is pretty small, basically taking up the equivalent of one rack. This is a relatively small transmitter room, the old tube transmitter basically took up the entire room. With this unit, there is room to install a full power spare, if that was desired.

GatesAir Flexiva series RF modules.

GatesAir Flexiva series RF modules.

RF modules use LDMOSFET devices, each module has a power output of approximately 1,600 watts.

GatesAir Flexiva FAX10 power amp section

GatesAir Flexiva FAX10 power amp section

There are eight power amp modules and seven switching power supplies.

GatesAir FAX10 transmitter on the air

GatesAir FAX10 transmitter on the air

GatesAir FAX10 power output

GatesAir FAX10, licensed transmitter power output

One issue at this site, there is no reliable three phase power available.  There was a three phase open delta, but man, that thing scares me a little bit.  Since this is a single phase setup, I was curious to know what the current draw on each leg was at full power. I measured with my clamp on ammeter; 54.3 Amps at 120 volts, or 6516 watts per leg. Overall power draw 13,032 making the AC to RF efficiency 65.2%. VSWR calculates out to 1.21, which is not great.  I think the antenna could use a little bit of tuning love.

A case for security cameras

I little bit of local awesomeness from the Putnam County Sheriff’s Department:

A Patterson (NY) man was committed to the Putnam County Jail in lieu of bail in connection with three separate thefts of copper fixtures from cell communications towers in Patterson and Kent.

The rest can be read here: Man charged with stealing copper from cellphone tower sites

I once got into an argument with my boss about transmitter site security cameras.  His attitude was “what difference does it make, nobody will do anything about it anyway.”  Clearly, if the police have something to go on, they will take action.  I know that several E911 sites in Dutchess and Ulster counties have been victims of copper theft as well.

IP security cameras are inexpensive and fairly reliable, provided you keep them out of the direct elements.  We have dozens of old Windows XP computers floating around which, with the addition of a software package like Blue Iris, can be repurposed as a record and save system.  The advantage of Blue Iris is the record on motion. The cameras do not need to be monitored continuously; if something happens, go back and look at the stored video.

The old Windows XP boxes do not need to be connected to the outside world unless one wants to look at the security system from the studio or home.   Alternatively, if one is Linux savvy, something like Zoneminder or Xeoma look like full featured video surveillance software packages.  I have not fooled around with these yet, but perhaps when I have some spare time…

The point is, for not too much money, a full featured video surveillance system can be installed at remote transmitter sites to keep track of comings and goings.  If enough idiots get busted for stealing copper, perhaps it will stop (or at least slow down).

North Adams Tower update II

Work continues on rebuilding the North Adams tower after the collapse of March 2014.  Over last winter, a new tower was erected.  This is a fairly substantial tower.

New North Adams tower on ground

New North Adams tower on ground

North Adams new tower erected

North Adams new tower erected

In the interim, a new Shively 6810 four bay half wave spaced antenna was ordered. This antenna will be combined for two stations, WUPE-FM and WNNI using a Shively 2630-2-06 branched combiner. The 70 foot utility pole next to the building will be retained as backup facility for both stations. The Shively Antenna went up in stages.

New WUPE-FM and WNNI Shively 6810 antenna

New WUPE-FM and WNNI Shively 6810 antenna

Tower climbers rigging tower for new antenna

Tower climbers rigging tower for new antenna

Prescott Tower from Rutland Vermont was on site to do the tower work. They were the primary contractor for installing the new tower and did a really nice job of it.

New North Adams tower ice bridges to various shelters

New North Adams tower ice bridges to various shelters

Hanging the top two bays of new antenna

Hanging the top two bays of new antenna

Lift of bottom two bays and first tuning section

Lift of bottom two bays and first tuning section

Securing bottom section and bolting bays together

Securing bottom section and bolting bays together

After that, there was twenty feet of rigid line, another tuning section, then the 1 5/8 inch helax into the transmitter room. The antenna was tuned and the load looks very good. We are waiting for the electrician to finish wiring up the new racks and we will move both stations into their new home.

For the Love of Radio

One of the guys I work with is a little bit crazy. Well… actually more than one, but this one person in particular has gone out of his way to fix up a summer camp radio station.  So, the background is this; in a remote region, far, far away from thing else, a summer camp had installed a license free (allegedly FCC Part 15) radio station to cover the camp compound.   Many summers later, said camp management had some questions and concerns about the operation.  This is where our protagonist comes into the story.

Not only did the camp owners have questions about their operation, they also had coverage issues.  Their installation consisted of a Ramsey five watt all in one FM transmitter feeding a horizontally polarized television antenna on the roof of the studio fed with RG-6 coax.  There were several coverage holes within the immediate camp complex and they were asking of a more powerful transmitter was needed.  In light of this, our man Pete did some engineering outreach.  Over the period of several months, Pete scraped together what would have been mostly back shelf backup gear, perhaps a few things destined for the dumpster and other miscellaneous items and built a small radio station for them.

Camp Radio Station equipment rack

Camp Radio Station equipment rack

What was once, no doubt, an illegal operation was brought substantially into compliance by replacing the Ramsey broadcast transmitter with a QEI 675 exciter modified by removing the power amp and connecting the IPA to the output filter.  Thus modified, it runs a maximum of 0.2 watts, which is not necessarily the output power. The antenna was changed to a home made vertically mounted dipole antenna.  The addition of a broadcast quality limiter ensures that the station is not over modulating.  A recently calibrated Belar FM modulation monitor confirms this.  Some Texar Audio Prisms juice up the sound a little bit.  A Urei console, a couple of Shure SM-58 microphones and a computer round out the operation.

Camp Radio Station console and computer

Camp Radio Station console and computer

Now, the camp radio station has the feel of a real radio station.  Kids that come here to do shows get a fairly authentic feel and appreciation for what it is like to be a DJ; selecting music, doing intros, information, weather, etc.  By looking at the sign up board, it seems that radio can still be very popular with teenagers:

Camp radio station sign up board

Camp radio station sign up board, very few openings

Thus the camp owner has perhaps saved himself some grief with the FCC.  A potential interference and intermodulation situation has been avoided.  The new equipment covers the entire camp compound and better still, does not go too far beyond the front gate, which is exactly 121.4 feet away from the antenna mast.  Best yet, a whole bunch of teenagers are interested in doing radio shows and learning about music.  There are very few venues or paths for potential new talent to enter this business and things like this should be encouraged.

Update: A few sentences were changed for clarity.

Hearing test

This was on the Wheatstone news letter a few months ago. NPR has an interesting test to see if one can hear the difference between various quality .mp3 and .wav files.  There are six cuts with three versions each; a 128 kbps .mp3, a 256 kbps .mp3 and a .wav file in no particular order.

That NPR article can be found here: How Well Can You Hear Audio Quality?

I listened to all of them and found the 128 kbps .mp3 was pretty easy to pick out.  On the newer material, it was sometimes difficult to tell the difference between the .wav file and the 256 kbps .mp3.  Keep in mind that most radio stations stream at 64-128 kbps.  Online music services like Pandora (64 kbps for free listeners, 192 kbps for subscribers), Spotify (96-160 kbps for free listeners, 320 kbps for subscribers) and Apple (256 kbps for everybody) offer slightly better quality, especially for paid subscribers.

It is too bad one cannot simulate 15 IPS analog tape.  I would bet that a well mastered recording on analog tape would stand out above anything even remotely compressed.

Others have compared streaming audio to analog FM audio and found that fairly high bit rates are needed to make the quality equal: What bitrate is needed to sound like analog FM?

One more thing to keep in mind, HD Radio runs 96-144 kbps on the main channel and 20-60 kbps on the sub channels.

Installation Check Lists

On the subject of project management; often times, we need to keep track of the small details that can derail a project, blow the budget and upset schedules. A quick check list can help to identify things that might not have been planned for. I developed a checklist mentality in the military. There, we had checklists for everything. Simple day to day things like disposing of garbage over the side, or pumping the CHT (sewage) tank to complex evolutions like entering or leaving port all had a checklist.  On the aforementioned CHT tank; the Coast Guard cutter I was on had a vacuum flush system to conserve water.  Emptying the CHT tank involved a complex set of valve openings and closings to rout compressed air into the vacuum tank and literally blow the sewage overboard.  Anyone can see the danger in such a design.  Failure to follow the exact procedure resulted in raw sewage blowing out of the nearest toilets, which were unfortunately (or perhaps humorously) in the lower level officer’s staterooms.

But I digress.

I have made a series of outlines for different project types.  These can be used as general guidelines for project planning and management.  Of course, each project is different, but these are flexible enough that they can be adapted on a project by project basis.

These are for general use, and should be adapted for your own purposes.  Don’t forget to document and label all the wire runs, etc.

Also, do not forget the transmitter site maintenance checklists: FM transmitter site maintenance list, AM transmitter site maintenance list. I have used these reliably at many different sites since I committed them to writing in late 1999.

Copper Thieves

If you are the type of person that drives around to transmitter sites and steals things; fuck you. You have no idea the problems you are causing to get a few extra dollars worth of scrap copper.

Missing copper ground buss bar

Missing copper ground buss bar

I have a feeling that most of these copper thefts can be attributed to out of town tower contractors removing old cellular equipment from towers.  Notice, only the buss bar and copper ground wire is missing.  They did not try to cut the transmission lines.  In other words, they seemed to know what they were doing.  I have noticed around here that a when a particular contractor, employed by an unnamed large company that rhymes with glint, would work at a site, things would be missing afterwards.

Perhaps it is just a coincidence. I have never been able to catch anyone pinching things. However, if this is you, and I catch you, you can rest assured that I will block you in with my car, then walk down the road and call the police.

The Voltair

I have put off writing anything about this for several reasons. First of all, there is a lot of secrecy surrounding the use of the Voltair magic machine. No one will admit to it, however, I have had several off the record conversations with various engineers.  All of this is hush-hush, unofficially off the record and on the QT, so no names, call letters or cities of license can be disclosed.

The general gist of these conversations is this; the Voltair seems to be increasing ratings in some cases and but not others.  It is sometimes too early to tell whether the increased ratings are a one time anomaly or something more permanent.  In one case, an AC station saw 30% increase in numbers, while a certain talk station saw next to nothing.  Results are mixed.

In the credit where credit is due department; the Telos Marketing campaign is has been effective.  Again, from a variety of different sources; Program Directors, Market Managers and Sales Managers are “beside themselves,” or “giddy”  when the UPS truck delivers the Voltair to the front door.  In one case, requiring that “I (the market engineer) drop everything” to get it installed as quickly as possible and “acting like it is God’s gift to radio.”  It looks like all those trade publication ads are paying off, $15,000 at a time.

Voltair PPM encoder enhancing device, in the wild

Voltair PPM encoder enhancing device, in the wild

One interesting thing about the Voltair, you can program simulated listening environments such as sporting events, restaurants, kitchens, vehicles, etc.  This allows the user to see how their program material is being decoded by a PPM survey device in those types of environments.  For example, if you are a sports station, having your program material decode well at sporting events or restaurants and bars might be important.

Of course, we have all seen the confidence display:

Voltair PPM encoder enhancer "confidence display"

Voltair PPM encoder enhancer “confidence display”

So, what does this mean?  Perhaps there is an inherent flaw in the Nielsen PPM encoding technology?  In the past, PPM has been blamed for the demise of the Smooth Jazz format.  I always had the notion that Smooth Jazz was responsible for the demise of the Smooth Jazz format.  However, if PPM is indeed causing certain program material to disappear from the airwaves, then it would be a case of the tail wagging the dog.  If PPM requires that station owner’s purchase a $15,000 in order to get credit for their TSL and cume, then there is a pretty big problem with the technical aspects of the system.

Of course, there are others that say there is no “Voltair effect.”  The Voltair machine is simply a fancy and expensive gizmo that looks good but does not really do anything.

Nielson Audio is having a Webinar on July 21 to address some of the questions regarding the Voltair and PPM encoding for subscribers only.  It will be interesting to see what the outcome is.

Cost saving measures

Excerpt of a memo from a few years ago, during the great recession:

(Redacted) has implemented a consumables reduction program.  All consumables; copy paper, toner, note pads, pens, pencils, paper towels, garbage bags, paper plates, plastic flatware, toilet paper, and so forth must be reduced by 25%.  (Redacted) is spending far to much on such material which is impacting our financial performance.

The Management

My contribution to the effort:

new consumable reduction program

new consumable reduction program

I wouldn’t want the CEO to miss his bonus this year…

Night of nights, 2015

Every year, the Maritime Radio Historical Society celebrates the closing of the last commercial Morse code radio station, which happened at 0001 UTC, July 13, 1999.  They do this by re-manning the watch for a few hours in honor of all those who so diligently listened for distress signals on 500 KHz and other frequencies continuously for over 90 years.  Your humble author was one of those, who in the late 1980’s and early 1990’s strained to hear, through the static crashes and OTHR, the simple, yet effective combination of SOS sent in Morse code.

Fortunately, after the closure of KPH, the National Parks Service took over the land and preserved the buildings and antenna fields intact.  Today, a dedicated group of volunteers maintain these facilities as a working museum.  This is the earliest history of radio technology and from this, sprang Amateur Radio, then Broadcast Radio services.

So, if you have the opportunity on July 12 (Sunday, starting at 8 pm, EDT), tune around to some of the frequencies listed below and see how ship to shore communications was handled:

KPH KFS KSM WLO KLB NMC NMW Ship transmit
426 426 488 472 448 425, 454, 468,480,512
500 500 500 500 500 500
2055.5
4247 4343 4184
6477.5 6383 6276
8642 8438.3 8658 8582.5 8574 8368
12808.5 12695.5 12993 12992 12552
17016.8 17026 16914 16968.5 17220.5 16736
22477 22280.5

These are duplex frequencies, meaning; the ship transmits on one frequency and listens on to the shore station on another and vice versa.

Those medium frequencies do not carry that far during daylight, however the high frequencies should be heard across the world.

In addition to that, there are youtube videos to watch:

There are more videos on youtube, if one is so inclined.

Those old RCA transmitter look like they are in excellent condition. Somebody has spent a lot of time restoring those units.

Hopefully, one of these years, I will get a chance to head out to San Fransisco during the middle of July and see this in person. It would be nice for my children to see what their old man used to do in what seems like a different lifetime.