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Power - TV Vertical Output ·Triode-Triode

20EW7

Dissimilar dual triode for television vertical oscillator and amplifier.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
-
Base pins
-
Nominal heater
20.5 V / 300 mA

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
20.5 V
Nominal heater current
300 mA
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

2 physical sections, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
8750 Ω
Transconductance
0.002 S
Amplification factor
17.5
Max plate voltage
330 V
Max plate dissipation
1.5 W

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
800 Ω
Transconductance
0.0075 S
Amplification factor
6
Max plate voltage
330 V
Max plate dissipation
10 W

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 01

1970 Sylvania Technical Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Plate Voltage

    250 V

  • Grid Bias

    -11 V

  • Plate Current

    5.5 mA

SECTION 2

Triode

Characteristics

  • Plate Voltage

    150 V

  • Grid Bias

    -17.5 V

  • Plate Current

    45 mA