7GS7

Combined triode-pentode for oscillator, mixer, frequency-converter, RF, or IF service in television, communications, or mobile receivers.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: -
Socket code: B9A
Base pins: 9
Nominal heater: 7 V / 450 mA

Description

Medium-mu triode and sharp-cutoff pentode frequency changer for VHF television tuners.

Socket description

Small-button Noval 9-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: B9A
Base pins: 9
Nominal heater voltage: 7 V
Nominal heater current: 450 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: 5000 Ω
Transconductance: 0.0055 S
Amplification factor: 17
Max plate voltage: 250 V
Max plate dissipation: 2 W
Max cathode current: 15 mA

Published ratings/characteristics promoted from supplied source; additional conditions retained in parameter table.

Section 2

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 435000 Ω
Transconductance: 0.012 S
Max plate voltage: 250 V
Max screen voltage: 150 V
Max plate dissipation: 2 W
Max screen dissipation: 0.5 W
Max cathode current: 18 mA

Published ratings/characteristics promoted from supplied source; additional conditions retained 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 01

1964 RMA EIA

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Heater Voltage
7 V
Heater Current
450 mA
Plate Voltage
100 V
Plate Current
14 mA
Transconductance
5500 uS
Amplification Factor
17
Plate Resistance
5000 ohm
Application
VHF frequency changer

SECTION 2

Pentode

Characteristic

Plate Voltage
150 V
Screen Voltage
150 V
Plate Current
10 mA
Transconductance
12000 uS
PlateResistanceMinimum
435000 ohm
Application
VHF mixer

Data set 02

1975 RCA RC30

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

Peak Heater-Cathode Voltage
200 V
AbsoluteValue
Average Heater-Cathode Voltage
100 V
AbsoluteValue

Characteristic

Typical Plate Voltage
100 V
ClassA;TriodeUnit
Typical Plate Current
14 mA
ClassA;TriodeUnit

SECTION 2

Pentode

Characteristic

Typical Plate Voltage
170 V
ClassA;PentodeUnit
Typical Screen Voltage
150 V
ClassA;PentodeUnit
Typical Plate Current
10 mA
ClassA;PentodeUnit
Typical Screen Current
3.3 mA
ClassA;PentodeUnit
Conversion Transconductance
4500 uS
FrequencyChanger