Ampera
D3A
Pentode · IHT · 8-pin Special · 1958
“German Postamt legend.”
Small-signal pentode for low-noise voltage amplification
Datasheet ↗SPICE
GAIN FACTOR0
PLATE IMPEDANCE0kΩ
TRANSCONDUCTANCE0mA/V
GAIN75%
POWER11%
DRIVE96%
LINEARITY63%
EXECUTIVE SUMMARY
The D3A is a indirectly-heated pentode from Siemens·Telefunken, introduced around 1958. It provides a gain factor (μ) of 75 with 4500Ω plate resistance. Commonly used in preamp / driver applications. German Postamt legend.
APPLICATIONS
Voltage amplifier
Generic pentode preamp / driver stage
HISTORY
Introduced1958ManufacturerSiemens·TelefunkenEquivalentsNone
Golden AgeSPECIFICATIONS
Heater Voltage20V
Heater Current0.1A
Max Plate Voltage250V
Max Power4.2W
Sensitivity16.5 mA/V
Gain Factor75
Internal Impedance4.5kΩ
Pinout8-pin Special
Era1958
RaritySought-after