WVAL transmitters and phasor are shown.
Transmitters and phasor for WHMH. In our Aug. 1 issue, Mark Persons and Mark Mueller gave you the technical details of the story “Four AM Stations Sharing One Site” (radioworld.com, keyword Mueller). The one thing it was missing? Visuals.
Now here is the accompanying artwork, previously left off, to help you get a better understanding of the project. Thanks to all who wrote in asking where the pictures were.
Mark Persons writes:
A new transmitter building was designed and constructed with the goal to expand from two stations to four stations. Transmitters and phasors from the two existing stations were moved from the original building to the new building and then the old structure was torn down.
More equipment was installed over the next few years for the additional two stations. The new building has a station in each of its four quadrants. This was done to better organize what was going on and to avoid confusion. A wise move because mixing it up in a building intended for less would have been a kluge.
RF and control wiring between the phasors and the antenna coupling networks were run through ports in the transmitter building’s concrete floor. This kept the installation very neat. No RF straps or other cables run across the floor. The rest of the cables are routed overhead. What a relief to be “trip hazard free” in the transmitter building.
A local handyman was employed full time to keep chipping away at the work under the direction station owners and myself. This saved a lot of money. In the end, I am extremely pleased that the facility turned out as well as it did. Mark Mueller is justifiably proud of his design and tuning on this amazing project.
One of the photos shows Mark using a high-voltage glove to adjust one of the many pass/reject filters. I first met Mark when he came to Minnesota to tune a five-tower directional antenna on 650 kHz, which I built from the ground up back in 1983. That one required constructing the phasor and antenna coupling networks with open-panel design from a schematic diagram and parts.
Yes, a phasor does not need to be purchased … it can be built locally, as were some sections of this four-station system.
Mark Persons, WØMH, is certified by the Society of Broadcast Engineers and has more than 30 years of experience as an engineer. He has written numerous articles for industry publications over the years. His website is www.mwpersons.com.
Gary Hoppe is on top of the world at WXYG and WMIN.The Hoppes: Herb, Val and Gary.
A high-voltage glove on a hot capacitor. Mark Mueller admires a tuning building.
Mueller tunes WXYG. Mark Persons stands by an entrance to the transmitter building.
Seven towers, one site. Sunrise at Sauk Rapids.