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Voltage Radio Detector Converter ·Pentode-Triode

6678

Combined triode-pentode used as an oscillator and mixer or frequency converter in television or VHF communications receivers.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: -
Socket code: IO
Base pins: 8
Nominal heater: 6.3 V / 450 mA

Description

Triode-pentode for VHF oscillator/mixer service in mobile communications equipment.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: IO
Base pins: 8
Nominal heater voltage: 6.3 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: 0.0085 S
Amplification factor: 40
Max plate voltage: 330 V
Max plate dissipation: 2.5 W
Max cathode current: 20 mA

Alias/co-designation of 6U8A;

Section 2

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 400000 Ω
Transconductance: 0.0052 S
Max plate voltage: 330 V
Max screen voltage: 330 V
Max plate dissipation: 3 W
Max screen dissipation: 0.55 W
Max cathode current: 20 mA

Alias/co-designation of 6U8A;

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

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Plate Resistance
5000 ohm
Transconductance
8500 µS
Amplification Factor
40

Other

Maximum Plate Voltage
330 V
Maximum Plate Dissipation
3 W
Plate Voltage
150 V
Triode section
Plate Current
18 mA
Triode section

SECTION 2

Pentode

Characteristic

Plate Resistance
400000 ohm
Transconductance
5200 µS

Other

Maximum Plate Voltage
330 V
Maximum Screen Voltage
330 V
Maximum Plate Dissipation
3 W
Maximum Screen Dissipation
0.55 W
Plate Voltage
250 V
Pentode section
Screen Voltage
110 V
Pentode section
Plate Current
10 mA
Pentode section

Data set 02

1960 RCA Industrial and Communications Types

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Heater Voltage
6.3 V
Heater Current
450 mA
EquivalentType
6U8A
RenewalUse

Data set 03

1965 Sylvania Electronic Tubes Vol3

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Heater Voltage
6.3 V
Heater Current
450 mA
EquivalentElectricalType
6U8A
Plate Voltage
100 V
Plate Current
10 mA
Transconductance
5000 uS
Amplification Factor
40

SECTION 2

Pentode

Characteristic

Plate Voltage
100 V
Screen Voltage
100 V
Plate Current
10 mA
Screen Current
3.5 mA
Transconductance
5200 uS
Plate Resistance
400000 ohm

Data set 04

1971 RCA HB3 Binder 3 of 7

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

Heater voltage
6.3 V
Nominal
Heater current
450 mA
Nominal
Maximum plate voltage
330 V
Promoted published value
Maximum plate dissipation
3 W
Promoted published value
Grid No.l to plate
0.006 mA
Direct Interelectrode Capacitances:
With heater voltage of
6 V
Characteristics, Class A I Amplifier:
Plate Supply Voltage
250 V
Characteristics, Class A I Amplifier:
Supply Voltage
110 V
Characteristics, Class A I Amplifier:
Cathode Resistor
68 ohm
Characteristics, Class A I Amplifier:
Plate Resistance (Approx.).
400000 ohm
Characteristics, Class A I Amplifier:
Plate Current
10 mA
Characteristics, Class A I Amplifier:
Grid-No.1 Voltage (Approx.)
1 V
Characteristics, Class A I Amplifier:
for plate µa
-10 V
Characteristics, Class A I Amplifier:
PLATE VOLTAGE.
330 V
Maximum Ratings, Design-Naximum Values:
SUPPLY VOLTAGE
330 V
Maximum Ratings, Design-Naximum Values:
tween
330 V
Maximum Ratings, Design-Naximum Values:
PLATE DISSIPATION
3 W
Maximum Ratings, Design-Naximum Values:
respect to cathode
200 V
Maximum Ratings, Design-Naximum Values:
much as
35 V
Maximum Ratings, Design-Naximum Values:
volts =
7.5 V
Maximum Ratings, Design-Naximum Values:
135 volts positive with respect to cathode, and al l other
135 V
Maximum Ratings, Design-Naximum Values:
With heater volts =
150 V
Maximum Ratings, Design-Naximum Values:
cathode resistor lohms) bypassed =
56 ohm
Maximum Ratings, Design-Naximum Values:
With heater volts =
250 V
Maximum Ratings, Design-Naximum Values:
2 supply volts = I
10 V
Maximum Ratings, Design-Naximum Values:

Characteristic

Plate resistance
5000 ohm
Promoted published value
Transconductance
8500 uS
Promoted published value
Amplification factor
40
Promoted published value
Voltage
20 V
Current at
0.45 V

SECTION 2

Pentode

Other

Maximum plate voltage
330 V
Promoted published value
Maximum plate dissipation
3 W
Promoted published value
Grid No.l to plate
0.006 mA
Direct Interelectrode Capacitances:
Grid-No.2 Current
3.5 mA
Characteristics, Class A I Amplifier:
PLATE VOLTAGE.
330 V
Maximum Ratings, Design-Naximum Values:
GRID-No.2 VOLTAGE - See Grid-No.a Input.
2 V
Maximum Ratings, Design-Naximum Values:
For grid-No.2 voltages up
2 V
Maximum Ratings, Design-Naximum Values:
For grid-No.2 voltages be
2 V
Maximum Ratings, Design-Naximum Values:
PLATE DISSIPATION
3 W
Maximum Ratings, Design-Naximum Values:

Characteristic

Plate resistance
400000 ohm
Promoted published value
Transconductance
5200 uS
Promoted published value