Ampera
KT61
Tetrode · IHT · Octal · 1940
“British beam tetrode. Smooth, refined.”
Beam power tetrode rated at 10W for high-power output stages
GAIN FACTOR0
PLATE IMPEDANCE0kΩ
TRANSCONDUCTANCE0mA/V
Cgk0pF
Cgp0pF
Cpk0pF
GAIN27%
POWER25%
DRIVE97%
LINEARITY87%
EXECUTIVE SUMMARY
The KT61 is a indirectly-heated beam tetrode from GEC·MOV, introduced around 1940. It provides a gain factor (μ) of 27 with 2750Ω plate resistance. Commonly used in power (se) applications. British beam tetrode. Smooth, refined.
HISTORY
Introduced1940ManufacturerGEC·MOVEquivalents6P25, CV1853
Pre-WarSPECIFICATIONS
Heater Voltage6.3V
Heater Current0.7A
Max Plate Voltage275V
Max Power10W
Sensitivity10.5 mA/V
Gain Factor27
Internal Impedance2.8kΩ
PinoutOctal
Era1940
RaritySought-after
Input Capacitance9pF
Miller Capacitance0.3pF
Output Capacitance8.5pF
SPICE model not yet available. Loadline calculator requires calibrated Koren parameters.