Ampera
6S4A
Triode · IHT · 9-pin Noval · 1965
“Russian medium-mu.”
Low-mu triode with excellent linearity for driver and line stages
Datasheet ↗SPICE
GAIN FACTOR0
PLATE IMPEDANCE0Ω
TRANSCONDUCTANCE0mA/V
Cgk0pF
Cgp0pF
Cpk0pF
GAIN6%
POWER21%
DRIVE99%
LINEARITY95%
TYPICAL OPERATING POINT
EXECUTIVE SUMMARY
The 6S4A is a indirectly-heated triode from Russian, introduced around 1965. It provides a gain factor (μ) of 6 with 600Ω plate resistance. Commonly used in driver applications. Russian medium-mu.
APPLICATIONS
Push-pull outputHeadphone output
Generic triode driver stage
• Headphone amp
HISTORY
Introduced1965ManufacturerRussianEquivalentsNone
Late ProductionSPECIFICATIONS
Heater Voltage6.3V
Heater Current1.2A
Max Plate Voltage250V
Max Power8.5W
Sensitivity10 mA/V
Gain Factor6
Internal Impedance600Ω
Pinout9-pin Noval
Era1965
RarityCommon
Input Capacitance4pF
Miller Capacitance1.5pF
Output Capacitance2.5pF