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KBIC-TV was one of the first UHF TV stations on the air in Los Angeles. The station was started by John Poole (1917-2003), then owner of KBIG-AM on Catalina Island. What became KBIC-TV first went on the air as an Amateur/Experimental station on Signal Hill (near Long Beach, CA), using an Army surplus transmitter. After licensing as a commercial station on Channel 22, the transmitter site was moved to Mt. Wilson, and a new General Electric TT-25-A transmitter was purchased. The transmitter was housed in a three story building. On the first floor was FM station KFMV-FM (Int. Ladies Garment Workers Union), power distribution and water coolers were on the second floor, and the KBIC-TV transmitter was on the third floor. There's also an attic that has windows facing south for microwave equipment. Note: Thanks to Steve Grimm and Tom Anderson for providing addition information on the call letters and building details.As far as I can determine, KBIC-TV never carried any programming material other than test patterns. In the earliest days, they actively solicited reception reports, and made arrangements to provide low cost, Army surplus, UHF converters to hams and other interested parties. After some time, the final amplifiers were sold to a station in Walla Walla Washington. They were operated there until that station went dark. The 100-watt exciter was retained by KBIC-TV and was used for testing. The amplifiers were returned to Mt. Wilson where they were stored for several years. The transmitter was then reassembled (after a thorough cleaning to remove the snake skins and rat dropping from Walla Walla!). Once back on the air KBIC-TV was sold, and became KIIX-TV, later KPOL-TV and finally, KWHY-TV.
I hope you find the following pictures (circa 1962-63) interesting.
Front view of the GE TT-25-A water cooled UHF TV transmitter. The cabinet at the left of the picture is the visual amplifier, the center unit is the 100-watt exciter, and the right cabinet is the aural amplifier. The small door in the front of each amplifier is access to the klystron for tuning. The klystron was tuned using a 7/8" open-end wrench. This adjustment actually changed the length of the tube. A joke associated with the tuning process was... you needed to be sure and adjust all the rods to the same length, less the tube become so crooked it couldn't be removed. The knobs near the top of the transmitter are used to adjust the current to the focus coils. You adjusted these for minimum body current, while at the same time, not getting the beam so sharp, that it could burn through the collector. As you adjusted the beam focus, you could actually hear the water cooling the collector begin to boil! The high voltage power transformers were located outside the transmitter building. The interconnecting high current, high-voltage, cables were very expensive!
(12.5 kw)
Many of the indicator lamps had individual step-down transformers, which were operated directly from the controlled circuit. The transmitter start and stop controls were large red and green buttons. You felt as if you were starting something more like a big printing press, rather than a TV transmitter. The actual power switching was done by three GE "contacters" (located on the lower floor). When the contacters operated, they made a very satisfying "clunk".
Also located on the lower floor were the radiators and air handlers for
the water cooling system.
This photo is from the aural end of the transmitter, and show the GE video monitor, and transmitter remote control panel. If you look closely, you'll see a waveform monitor just below the picture monitor. This was driven from a diode detector (1N21A) at the output of the visual amplifier. This signal also included a chopper for determining modulation. The chopper was a vibrating reed relay.
The klystrons were shipped in round metal containers. It took about half a day to "dress" the tube, and among other tools, required a chain hoist.
The same tube can be used in either visual, or aural amplifier. In
an emergency, you could run both the visual and aural signals through
a single tube.
To some, a water cooled transmitter has two significant advantages, first, its quiet and second, the transmitter stays much cleaner.
As with so many things there are sometimes unintended consequences... and
you get the inside of the transmitter washed when a cooling hose breaks!
Power was determined by measuring the temperature difference between
the water entering and leaving the dummy load.
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This photo shows a fully dressed klystron in its installation cart. To install
the tube in the transmitter, you rolled this cart to the rear of the
amplifier, and rolled the tube off the cart and into the amplifier cabinet.
The GE transmitter was water cooled. This photo shows the two air handlers
for the water cooling radiators. The square box in the foreground is the
water storage tank. The system was filled with distilled water.
Water cooled dummy load for testing the transmitter.
