Sharp-Cutoff Pentode
The 8425A / 6AU6A Vacuum tube is a miniature type used in compact radio equipment as an RF amplifier
especially in high-frequency, wide-band applications. The 8425A tube is intended for various
industrial applications. It is also used as a limiter tube in FM
equipment. This tube requires a miniature 7-contact socket and may be mounted in any position.
Electrical Data:
Heater Voltage ................................ 6.3 V
Heater Current ................................ 0.3 A
Heater Warm-up Time ........................... 11 s
Maximum Heater-Cathode Voltage:
Heater Positive with Respect to Cathode
DC Component ............................ 100 V
Total DC and Peak ....................... 200 V
Heater Negative with Respect to Cathode
Total DC and Peak ....................... 200 V
Preferred Substitutes: ......................... 6136, 6AU6A, 6HS6
Substitutes: ................................... 6AG5, 6AH6, 6BA6,
6BC5, 6CE5, 6CG6, 6HR6, 6AH6.