July 2013 – Engineering Radio

Happiness is: An AM directional array at licensed values

Last week I did some repair work at WDDY in Albany NY. It seems the sample line on one of the towers was melted in half by a lightning strike. This station uses sample loops up on the tower for its directional antenna monitoring system.

As it happened, the sample line in question was on the reference tower, which makes everything else meaningless. Before the meltdown, there were several years’ worth of maintenance logs that showed the previous values for current ratio and phase relationship.

With the transmitter turned off and locked out, I removed the damaged section of the line from the base of the tower to the RF choke coil in the tuning house. Where the sample line came off of the base of the tower, there was a UHF-type connector that had been improperly applied. Using spare parts, I fixed that connector, then spliced the line into place. Upon power-up, the transmitter and antenna readings returned to their previous values, which were slightly out of tolerance.

Thus, some phasor tuning was needed. There are not too many people left that can properly tune an AM phasor. All of the control interact with each other; moving the power or phase to one tower will likely affect all of the other towers and possibly the reflected power on the transmitter. This phasor was made in the 1970s by Multronics with what looks like all RCA parts. Multronics, I think, was John Mullaney who is more known for the folded unipole antenna. In any case, after a good few hours of careful hand cranking and a run out to the reference tower to move a coil tap, here are the results:

Not bad for a day’s work.

Clove Mountain

We take care of a non-broadcast radio site on Clove Mountain, NY. This is a fairly prominent terrain feature and has something else interesting next to the tower site. This old fire tower:

That is an Aermotor LS-60 fire tower, constructed in 1932. For an eighty-year-old structure, it is a remarkably good shape. In New York State, fire towers were used for spotting up until 1990, although I believe the last season this one was used was 1988.

Clove mountain is about 1,400 feet above sea level and 800 to 1000 feet above the surrounding terrain. From the top, on a clear day, the view was approximately 30-45 miles depending on terrain obstacles. A forest ranger would be constantly scanning the area looking for signs of fire. If he saw something, there was a range finder that would give the range and azimuth. He would then reference a map and call the fire department responsible for that location. The fire tower was equipped with electric and a wired telephone.

This picture was taken on a cloudy day, thus the view is somewhat restricted.

It would be nice if this were preserved and not allowed to deteriorate any further. Several of these sites have been placed on the National Register of Historic Places.

Below the tower is this ranger cabin. Presumably, during the busy season, somebody stayed up here 24/7. There was electricity and a refrigerator, but no running water. Off to the side is a bedroom. Over the years, people have broken into the fire tower and this cabin and smashed things for no reason. It would be nice to preserve all of this for future generations to see, but it is likely these pictures will have to do.

New Studio Project, Part II

The finished product:

This is the finished product from an earlier post. Currently, it is the studio for WAJZ in Albany, but that is not permanent. The SAS studio goes together fairly quickly, as most of the trunking between the TOC and studio is done over the SAS data channel.

The studio monitors (Tanoy Reveal) are set on little posts under the computer screens. I like this setup as the DJs are less likely to rock the house if they decide to crank up the volume on their favorite tune. I am also kind of digging the lack of a tabletop equipment pod. That takes up a lot of countertop space and always seems to be in the way. There are two CD players racks mounted below the counter (lower left), which are almost never used.

WDST, Woodstock, New York

WDST is a well-known radio station in Woodstock, NY. Formatically, I would call it Adult Album Alternative (AAA) and it is one of my favorite stations to listen to. We also do the engineering work for this station. While I was there last week, I snapped a few pictures of the studios:

All of the studio use Audioarts R-60 consoles, which are in good condition considering their age. Lots of guest microphones and the windows look out into a performance venue.

WDST music library, located in hallway outside of studio — WDST music library, located in the hallway outside of the studio

The music library is extensive.

The production room, another R-60 console. I don’t know where the microphone disappeared to, perhaps it was borrowed by the morning show.

Technical Operation Center (TOC). WDST uses NextGen from RCS for music storage, playback and automation. Other equipment includes ISDN, POTS phone, Distribution Amps, Limiters, streaming computer, STL, etc.

WDST transmitter, Broadcast Electronics FM5C

The transmitter site is on Hallihan hill, across the street from the old ATT long lines site. The station uses a Broadcast Electronics FM5C transmitter.

Forward power, almost five whole kilowatts of flame throwing power.

WDST antenna, Hallihan Hill, Kingston, NY

The antenna is a Shively 6810 2-bay half wave spaced.