Heater-to-Cathode Voltage (max)Max Heater-Cathode Voltage (heater negative, DC)500V
Rectifier
Peak Inverse VoltageMaximum Peak Inverse Plate Voltage (absolute)3,850V
Voltage Drop (typical)Tube Voltage Drop (at 250 mA)21V
DC Output Current (max)Maximum DC Plate Current125mA
Peak Anode Current (surge)Maximum Peak Plate Current750mA
other
Direct Interelectrode Capacitance: Plate to Cathode and Heater (P to K+H)Direct Interelectrode Capacitance: Plate to Cathode and Heater (P to K+H)6pF
Direct Interelectrode Capacitance: Cathode to Plate and Heater (K to P+H)Direct Interelectrode Capacitance: Cathode to Plate and Heater (K to P+H)13pF
Direct Interelectrode Capacitance: Heater to Cathode (H to K)Direct Interelectrode Capacitance: Heater to Cathode (H to K)7pF
Heater
Heater VoltageHeater Voltage6.3V
Heater CurrentHeater Current1.2A
Notes
Base is 4CG (Short Intermediate Shell 6-Pin Octal). Pins 1, 3, and 8 should not be used as tie points. Pin 2 is an internal connection.
TDSL lists CV732 as a close/identical substitute and 6W4GTA as a different rating/performance substitute. 25W4GT is the series-string heater equivalent (25V).
Brans Vademecum table VIIb cross-lists 6W4 with CV732.
MIL-HDBK-213A classifies as 'Receiving full wave rectifier' and lists 6W4GTA as the other number for 6W4GT. Despite the MIL classification as 'full wave', the 6W4GT is a half-wave rectifier/damper diode.
GE Essential Characteristics lists max plate dissipation as 3.5 W for TV damper service.
The Brans damper group (table VIIb via 6AX4GT) lists many damper types in the same equivalence group including 6AX4GT, 6DE4, 6DQ4, 6U4GT, and 6W4(GT), but these have different PIV ratings and may not be direct substitutes in all circuits.
Heater-cathode voltage limits: 500 V DC (heater negative), 2300 V peak (heater negative), 100 V DC (heater positive), 300 V peak (heater positive).