Transmitter Room Fire Reported at Sears Tower

Several years ago, I wrote about an innovative HV power supply Itelco offered for their high power UHF transmitters. The power supply used a long string of diodes and capacitors to multiply the voltage from a lower voltage power supply to the approximately 30 kV needed to operate a high power IOT amplifier. Last week, from photos I saw, it appears one of these HV supplies caught fire on the 101st floor of Sears Tower. Fortunately, there were no injuries and while other transmitter rooms on the same floor were filled with smoke and soot, there was little damage to those facilities.

According to the Chicago Tribune, the fire was reported at 1:47 a.m. last Wednesday morning.

The Itelco transmitter belongs to Univision-owned station WXFT-TV, which operates on Channel 60.