We recently put an LPTV on the air in Brookfield, Connecticut. WXGN-LD signed on on Friday, September 6th.
This is UHF station with a 15 KW ERP (the limit for LPTV). This station has an elliptically polarized antenna with 4.5 KW in the vertical polarization.
The transmitter is made by a Spanish company called TRedess
TRedess 4th series 4 amplifier UHF transmitter capable of 3 KW on ATSC 1.0GUI is easy to navigate and understandDielectric six-pole full-service mask filter
This has been installed in a former Sprint cell building. The wire ladders are left over from them. Still, it makes a convenient place for the mask filter, which is up and out of the way.
Standard work table and two chairsMaking spectrum mask measurements
I also swept the antenna and filter.
This station is associated with these folks: XGN Network LLC
Over the last several months, I have been helping out in a small way with WFUV’s new transmitter installation. George Evans, CE for WFUV, and Bill Weeks of Wolftron Electronics did most of the work. This project’s location is unique; the transmitter is in an equipment shelter on top of the Montefiore Medical Center in the Bronx. That complicated the removal of the old transmitters and installation of the new transmitters.
WFUV tower atop the Montefiore Medical Center
This is the top of the Montefiore Medical Center in the Bronx. The building has 28 floors. To access the transmitter, one needs to go up another flight of stairs to the roof. Go outside onto the roof and take two more flights of stairs to the transmitter shelter just below the tower. Those stairs can be seen as a thin wispy thing on the left of the elevator building.
WFUV tower, close up
At the top of the tower, the two-bay Shively antenna is for WVBN 103.9 Mhz. WFUV 90.7 MHz is the six-bay Shively just below that.
BE FMi 703 (FM-10S)
These are the transmitters being replaced. There are two of them running combined for a TPO of 14.2 KW (including the -14 dBc HD subcarriers). They are about 20 years old.
The before picture; combined BE FMi 703 transmitters
As you can see, there is little room to work in this space. The old transmitters needed to be removed from the room, hosted down two stories to the main rooftop, wheeled around to the door, and then lowered another flight of stairs to the 28th to the elevator.
It makes me tired just thinking about it.
BE FMi 703 (less RF modules and power supplies) being lowered to the rooftop level
Out with the old, in with the new.
GatesAir FAX15K being hoisted from the roof up to the transmitter shelter
The GatesAir FAX15Ks made the trip up safely. Able Rigging from New Jersey did all of the moving into and out of the shelter. The two transmitter chassis, all of the boxes containing the exciters, RF modules, power supplies plus a 25 KW dummy load, and the cut-up for scrap Myat variable T antenna combiner were removed in one go.
The after picture; GatesAir FAX15K transmitters, two cabinet version
The FAX15K’s are in the shorter cabinets (requires two) because the taller cabinet would not fit in the elevator.
FAX15K with back doors removed, power block, combiner, directional coupler, and RF output flange.3-inch coax switch and RF plumbing
The output of each transmitter goes to a 3-inch coax switch. The bottom port of the switch goes to the Shively filter (thence to the antenna), and the top port goes to the 20 KW dummy load.
3-inch coax switchBill Weeks routing control wiring to coax switchWFUV CE George Evans, heading to the job site“How many more times do I have to climb these stairs today?”But the view is great! Mid and upper Manhattan in the distanceYour author is about to tell a sea story…
This is another SAS console installation for WHUD licensed to Peekskill, NY.
Rack Room wiring, 32KD router for WHUD and WSPKSierra Automated Systems 32KD routerSAS Gear; RIO BravoEthernet patch panel and trunk wiring to rack roomNetwork Switch and mic preampsRubicon Console, Studio Technologies FurnitureJust prior to going on the air
One of our clients needs to move to another transmitter site because their lease is expiring at the old site. We have been working on this for several months now. One of the nice features of this project is the panel antenna.
Kathrein 754154 spec sheet
This is installed in a 2-bay 3-around configuration. I don’t see this particular model in the Kathrein catalog anymore, but there are other cross-polarized panel antennas available from them.
Colocated tower
There are many existing services on this tower including two full-power FM stations, a translator, a VHF TV station, numerous cell carriers, etc. Once the installation is done we will have to check carefully for intermodulation.
Honda Track Machine
Winter in the Northeast; there was just enough snow and slush on the access road that the truck could not make it to the top of the hill. This track machine works great. We have added a Polaris Ranger 900 to our inventory (not this machine) for winter access to several of the more difficult transmitter sites. While I do enjoy the occasional walk in the snow, the key word here is occasional.
AAT branch combiner inputs
The three stations are combined into the panel antenna with this rather nice American Amplifier Technologies C-IR-3-3-30K-N branch combiner.
AAT branch combiner output side
The input filters needed a slight adjustment to compensate for the difference between the test load they were tuned to and the actual antenna load they will be running into
Touching up input filters
Two of the transmitters are Broadcast Electronics STX-10 units. We have had good service from the STX-10 which was installed on Mount Beacon a few years ago.
Pair of BE STX-10 transmitters
We are waiting for the Comrex Bric Link III to come back from the factory after their firmware update. They are to be used for the STL. Once they are returned, we should be good to go for site turn-up.
