Data set 01
1950 General Electric Transmitting Types
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Maximum full-rating frequency
6 MHz
Application
Service
RF power amplifier / oscillator / audio modulator
Power - Triode ·Triode
242C
Filamentary transmitting power triode intended for RF amplification and oscillation. Manufacturer documentation provides power-service operating conditions characteristic of transmitter output or driver stages.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- J4
- Base pins
- 4
- Nominal heater
- 10 V / 3.25 A
Description
The Western Electric 242C is a triode listed in the supplied catalog table. It is an air-cooled transmitting type intended for RF power service.
Socket description
Jumbo 4-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- J4
- Base pins
- 4
- Nominal heater voltage
- 10 V
- Nominal heater current
- 3.25 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
- 3500 Ω
- Transconductance
- 0.0036 S
- Amplification factor
- 12.5
- Max plate voltage
- 1250 V
- Max plate dissipation
- 100 W
- Max cathode current
- 150 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
1956 Western Electric Tubes
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Maximum/Typical Power Output
50 W
Catalog-table value
Other
Maximum Plate Voltage
1250 V
Catalog-table value
Maximum Plate Dissipation
100 W
Catalog-table value
Data set 03
2026 Western Electric 200s
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
Filament voltage
10 volt
Filament voltage 10 volts, a.c. or d.c.
Nominal fi l a m e n t current
3.25 amperes
Nominal fi l a m e n t current 3.25 amperes
Average thermionic emission
1.5 amperes
Average thermionic emission 1.5 amperes
A m p l i fi c a t i o n factor
12.5
A m p l i fi c a t i o n factor 12.5
Plate resistance
3500 ohms
Plate resistance 3500 ohms
Grid to plate transconductance
3600 micromhos
Grid to plate transconductance .... 3600 micromhos
Direct plate voltage
1250 volt
Direct plate voltage 1250 1000 volts
Grid bias
-6 volts
Grid bias - 6 8 — 42 volts
Direct plate current
68 milliamperes
Direct plate current 68 85 milliamperes
Plate dissipation
85 watts
Plate dissipation 85 85 watts
Load impedance
8000 ohms
Load impedance 8000 7000 ohms
Undistorted output
22 watts
Undistorted output 22 12 watts
Grid bias
-8 volts
Grid bias - 8 0 — 60 volts
Plate dissipation
100 watts
Plate dissipation 100 100 watts
Load resistance plate-to-plate
7600 ohms
Load resistance plate-to-plate 7600 6000 ohms
Load resistance per tube
1900 ohms
Load resistance per tube 1900 1500 ohms
Direct plate current for carrier conditions
120 milliamperes
Direct plate current for carrier conditions.... 120 150 milliamperes
Grid bias
-9 volts
Grid bias - 9 0 — 70 volts
Direct plate current
150 milliamperes
Direct plate current 150 150 milliamperes
Grid bias
-150 volts
Grid bias —150 to —200 — 120 to —160 volts
Nominal power output
130 watts
Nominal power output 130 100 watts
Plate dissipation
57.5 watts
Plate dissipation 57.5 50 watts
Direct plate voltage
750 volt
Direct plate voltage 750 volts
Direct plate current
150 milliamperes
Direct plate current 150 milliamperes
Grid bias
-120 volts
Grid bias —120 volts
fuse or circuit breaker should remove the plate voltage if the plate current exceeds
175 volt
fuse or circuit breaker should remove the plate voltage if the plate current exceeds 175 milliamperes.
circuit, reduced plate voltage or a series resistance of
1000 volt
circuit, reduced plate voltage or a series resistance of 1000 to 5000 ohms in the plate circuit should
A
5 volt
A 5% decrease in filament voltage reduces the thermionic emission approximately 25%. Either
A resistance of
20 ohms
A resistance of 20 to 30 ohms of three watt rating is suitable.
voltages off,
30 volt
voltages off, 30% above normal voltage for 10 minutes followed by a longer period at normal voltage.
on the basis of
5
on the basis of 5% second harmonic distortion.
of the plate voltage. For complete or
100 volt
of the plate voltage. For complete or 100% modulation, the plate voltage varies from zero
fourth of the peak power output under
100 volt
fourth of the peak power output under 100% modulation. In this case, since the plate voltage
Other
Max. direct plate voltage
1250 volt
Max. direct plate voltage .... 1250 volts
Max. direct plate current
150 milliamperes
Max. direct plate current .... 150 milliamperes
Max. plate dissipation
100 watts
Max. plate dissipation .... 100 watts
Max. direct grid current
50 milliamperes
Max. direct grid current 50 milliamperes
Max. r-f grid current
5 amperes
Max. r-f grid current .... 5 amperes
Max. frequency for the above ratings
6 megacycles
Max. frequency for the above ratings .... 6 megacycles
Max. plate voltage for upper frequency limit o f
30 volt
Max. plate voltage for upper frequency limit o f 30 Mc .... 600 volts
Max. plate voltage for frequencies between
6 volt
Max. plate voltage for frequencies between 6 and 30 Mc in proportion
Approximate max. output
2 watts
Approximate max. output—2 tubes 200 165 watts