During the late 1940's and early 1950's much of television engineering was in what may be termed the 'experimental' stage. Most VHF transmitters were limited to about 5 KW peak visual power and about half that power for the aural. The General Electric Company built one of the first really 'large' high band amplifers that would take the 5 KW of an early RCA, Federal or GE TT-6 and bring it up to a full 50 KW peak visual and 26.5 KW FM for the aural. This amplifier was very popular and this basic design was in use until GE retired from the transmitter field in the late 1960's. Only the tubes and a number of parts were updated. The TT-35 series (of which this amplifier with a TT-6 driver would make) stayed in the field for many years. Notable stations used the TT-35 package. WHAS-TV and KSL-TV are but two of those notable stations. (KRNT-TV, now KCCI, was another...)

Description from: http://louise.hallikainen.org/BroadcastHistory/index.php/GeneralElectric Manual from my collection, courtesy of KCCI engineers Ken Drewes and Al Snyder; scan by Stan Adams. 20-megabyte file.