Data set 01
1956 Western Electric Tubes
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Maximum Plate Voltage
400 V
Catalog-table value
Power - Triode ·Triode
205F
Power-output triode intended for amplifier service, using a directly heated filament and operating conditions suited to appreciable audio-frequency output. The documentation places it in power rather than small-signal triode service.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- MEDIUM4BAYONET
- Base pins
- 4
- Nominal heater
- 4.5 V / 1.6 A
Description
The Western Electric 205F is a triode listed in the supplied catalog table.
Socket description
Medium 4-contact bayonet base
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- MEDIUM4BAYONET
- Base pins
- 4
- Nominal heater voltage
- 4.5 V
- Nominal heater current
- 1.6 A
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
Terminal pinout
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
Section ratings
1 physical section, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 3700 Ω
- Transconductance
- 0.00195 S
- Amplification factor
- 7.2
- Max plate voltage
- 400 V
- Max plate dissipation
- 12.5 W
- Max cathode current
- 50 mA
Promoted fields mapped from published ratings/characteristics; additional published values preserved in parameter table.
Source-dependent data
Operating conditions by source
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 02
2026 Western Electric 200s
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
Filament Voltage
4.5 Volt
Filament Voltage 4.5 volts
Plate Current ) Eb =
350 volts
Plate Current ) Eb = 350 volts; 35 milliamperes
Power Output I Ec =
-22.5 volts
Power Output I Ec = —22.5 volts 880 milliwatts
ii voltage, A-C or D-C
4.5 volt
-...ii voltage, A-C or D-C . 4.5 volts
Filament Current
1.6 amperes
Filament Current .... 1.6 amperes
Output
2.2 uuf
Output 2.2 uuf
Plate Voltage
360 Volt
Plate Voltage 360 volts
Plate Current
50 milliamperes
Plate Current . 50 milliamperes
Plate Dissipation
12.5 watts
Plate Dissipation 12.5 watts
Filament Voltage, A-C
4.5 Volt
Filament Voltage, A-C .... 4.5 4.5 4 S 4.5 v o l t s
Plate Voltage
250 Volt
Plate Voltage 250 300 350 350 volts
Grid Voltage*
-2 Volt
Grid Voltage* - 2 2 - 1 8 -22.5 - 2 2 . 5 volts
Zero Signal Plate Current
11 milliamperes
Zero Signal Plate Current 11 . 5 30 35 35 milliamperes
Plate Resistance
5300 ohms
Plate Resistance 5300 3800 3700 3700 ohms
Amplification Factor
7.2
Amplification Factor 7.2 7.2 7.2 7.2
Total Harmonic Distortion
4.6
Total Harmonic Distortion 4.6 1.6 2.8 1.4 p e r c e n t
if the grid voltage, measured from the negative filament, is decreased by
23 volt
if the grid voltage, measured from the negative filament, is decreased by 23 volts.
Other
Maximum Signal Plate Current
12 milliamperes
Maximum Signal Plate Current . 12 30.5 36 36 milliamperes
Maximum Signal Power Output
550 watts
Maximum Signal Power Output . 550 450 880 760 milliwatts