Small piece of SDPB history tumbles

Small piece of SDPB history tumbles After the AM radio tower toppled, bystanders get a closer look at the structure that once stood 285 feet tall. by M. Jill Sundstrom With the aid of nylon ropes, an axe and gravity, a piece of South Dakota Public Broadcasting history has tumbled to the ground.

No longer needed for AM radio broadcasting, the SDPB tower north of the former Vermillion Golf Course was taken down Oct. 14.

�Sioux Falls Tower Specialists, our primary tower contractor, rigged it so it could be dropped safely,� said Don Forseth, technical services coordinator for SDPB. �They tied ropes to half of the guy wires, and when they were cut, the remaining wires pulled the structure down, with the help of gravity.�

The 285-foot tower was one of two built in 1950-51 when the radio station was moved from The University of South Dakota campus to the site north of the golf course. But since 1994, there has been no AM radio station, for a variety of reasons, Forseth said. An accident on Dec. 20, 1992, in which a vehicle struck one of the guy wires of the other tower, causing it to collapse, played a big role in the ultimate decision to surrender the AM license.

�We had been agonizing over the fate of the AM station for a long time, especially after the accident,� he said. �With two towers, we made the best use of our signal, but we weren�t able to cover a significant population in South Dakota with the pattern and power that KUSD was allowed to operate on.�

As technology grew, interference increased and FM radio was becoming more popular.

�After talking with a consultant, we were told if we stayed on that frequency, there wasn�t much chance to increase our power or pattern,� Forseth said. �They didn�t think it was worth spending the money and time to investigate other channels because the AM band was essentially full.�

Still, SDPB had spent a fair amount of time and money already, rebuilding the physical portion of the transmitter and towers.

�We had replaced two antenna tuning units, along with a phasing unit,� Forseth said. �In late 1992 we were just getting ready for the next budget cycle to do more work, then the accident happened.�

Because the driver of the vehicle that clipped the guy wire had little insurance, �there wasn�t enough money to put the tower back up and do the work that was necessary to make it like new again,� Forseth said. �We ran on less power for awhile, which further reduced our coverage area. But by 1994, we decided to turn the AM station off and surrender our license to the FCC.�

The insurance money was then used to upgrade the SDPB FM signal in Aberdeen, Huron and Pierre.

Since then, the remaining tower has been maintained and options for its use were studied.

But its age, the fact that it was constructed with brittle steel and its location made it undesirable for future use.

�It would have cost too much to take it down piece by piece,� Forseth said. �So we decided to drop it as an educational exercise for our engineering staff.�

The tower will eventually be dismantled for scrap.

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