6F6 NOS Western (misc brand)

6F6 vacuum tube

• General-purpose audio output pentode for domestic and car radios
• Originally introduced in the mid-1930s, well established before WWII
• Output power roughly comparable to the 6V6 tube
• Higher sensitivity than the 6V6, can be driven directly from the detector output
• Allowed simpler amplifier designs, especially in compact car radios
• Larger cathode and higher heater power requirement compared to the 6V6
• Tends to run hot; de-rating commonly recommended in car radio use
• Specified operating values apply to single-ended use with a 7,000 Ω anode load
• In push-pull class A operation, up to 10.5 W output with approx. 3% distortion
• Equivalent types: KT63 (beam tetrode), Type 42 (6.3 V heater), 2A5 (2.5 V heater)