Paul Thurst – Page 54 – Engineering Radio

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 pillage 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, nonetheless.

Therefore, we celebrate our independence and revel in our freedoms that were so hard won. Freedoms to do things like speak our minds, own firearms, and enjoy limited government intrusion in our lives. As human beings, we have rights to legal safeguards that ensure the legal system will not be abused. We enjoy the freedom to travel within our own borders unmolested. We can worship or not worship in any way 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 appears to be eating into Microsoft’s and Apple’s market share.

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 make 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:

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 un-aware? 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 times 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 farmland 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

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

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

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

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 straightforward, 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

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:

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 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 (STLs, Exciters, remote controls, etc) a backup QEI transmitter, an Onan generator transfer switch:

Killington Peak fire tower, WJJR WZRT transmitter building

Both stations run into this ERI half-wave spaced 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.

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

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