The KT44 (and the almost identical KT45) beam tetrode on a B7 base is described for both audio use and television line output service. In the television role the valve can withstand a positive anode surge of 8,000 volts and it was television service it was mainly specified. The KT series are mainly known, however, as audio devices and it is believed that the KT44 was a four Volt type developed from the KT66. The anode connection is taken to a top cap so that the valve can withstand high peak anode voltages.
The classic envelope is 52 mm in diameter and, excluding the B7 base pins, is 130 mm tall.
References: 1043. Type KT44 was first introduced in 1939.
Absolute Maximum Operating Conditions¶
Updated February 11, 2017.