*** The Ampliphase Ancestry ***
The BTA-50G Ampliphase
The BTA-50G was released in 1955, the first unit shipped to WINS, New York, on 28th December 1955, and went into service shortly afterwards. The unit was extensively described in the August 1955 issue of RCA's "Broadcast News", pages 54 - 59.
One notable feature in the article is "Fig 5" as shown below, which shows the inside of the exciter cabinet.
The June 1957 issue of "Broadcast News" also carried a feature on the 50G, but the pictures in that article show the later style modulator, and the drive regulator has mysteriously appeared in the bottom of the cabinets.
The transmitter also featured Mercury Arc rectifiers for all the high voltage supplies, of 2.5Kv, 5Kv and 15Kv. The rectifier cabinet housed no less than 18 such tubes, all fed from their own, highly insulated filament transformers, as shown in the diagram below.
Note also the heater panel on the rear of the door consisting of 4R41 to 4R47, to keep the ambient temperature high enough for the tubes to operate.
If you can shine any light on any version of ampliphase please feel free to contact me. In particular I would appreciate handbooks and photographs for the five and ten.
I really appreciate all feedback to these pages. Thanks!
My email address is: "ampliphase [at] radio [dot] fm" or use the feedback form on the left menu.