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Voltage Radio Detector Converter ·Heptode

6SA7

Widely used pentagrid oscillator-converter for superheterodyne receivers. Its multi-grid structure combines local oscillation and mixing in one tube, making it a common receiver frequency changer.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: RETMA 8R
Socket code: IO
Base pins: 8
Nominal heater: 6.3 V / 300 mA

Description

Single-ended pentagrid converter for oscillator and mixer frequency-conversion service.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: RETMA 8R
Socket code: IO
Base pins: 8
Nominal heater voltage: 6.3 V
Nominal heater current: 300 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

RETMA 8R - 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

Heptode

X-ray radiationInterelectrode capacitances

Plate resistance: 500000 Ω
Transconductance: 0.00045 S
Max plate voltage: 300 V
Max screen voltage: 100 V
Max plate dissipation: 1 W
Max screen dissipation: 1 W
Max cathode current: 14 mA

Conversion and oscillator characteristics are preserved as parameters rather than promoted as generic transconductance.

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

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

HEATER VOLTAGE (A.C. or D.C.)
6.3 V
HEATER VOLTAGE (A.C. or D.C.) 6.3 Volts
HEATER CURREN
300 mA
HEATER CURREN 0.3 Ampere
Plate to All Other Electrodes (Mnxer Qutput) ©
12 pF
Plate to All Other Electrodes (Mnxer Qutput) © 12 puf
Grid #3 to Plate © 0.13 max, uuf
0.13 pF
Grid #3 to Plate © 0.13 max, uuf
Grid #1 to Grid #3 © 0,15 max., uuf
15 pF
Grid #1 to Grid #3 © 0,15 max., uuf
Grid £1 to Plate© 0.06 max. puf
0.06 pF
Grid £1 to Plate© 0.06 max. puf
PLATE VOLTAGE 250 max, Volts
250 V
PLATE VOLTAGE 250 max, Volts
GRIDS #2 & #UI VOLTAGE 100 max. Volts
100 V
GRIDS #2 & #UI VOLTAGE 100 max. Volts
TOTAL CATHODE CURRENT 14 max, Milliamperes
14 mA
TOTAL CATHODE CURRENT 14 max, Milliamperes
Heater vVoltageD 6.3 6.3 6.3
6.3 V
Heater vVoltageD 6.3 6.3 6.3 6.3 volts
Plate voltage 100 250 100
250 V
Plate voltage 100 250 100 250 volts
Grids #£2 & i4 voltage 100 100 100
100 V
Grids #£2 & i4 voltage 100 100 100 100 Volts
Volta3 0 0 -2
-2 V
Volta3 0 0 -2 -2 Volts
Shell & Grid ¥5 Voltage 0 0 0
0 V
Shell & Grid ¥5 Voltage 0 0 0 0 Volts
Grid #1 Resistor 20000 20000 20000
20000 ohm
Grid #1 Resistor 20000 20000 20000 20000 ohms
Conversion Yranscond, 425 450 125
450 µS
Conversion Yranscond, 425 450 125 450 Micromhos
= 5 micromhos -35 -35 -35
-35 V
= 5 micromhos -35 -35 -35 -35 volts
Plate Current 3.2 3.4 3.2
3.4 mA
Plate Current 3.2 3.4 3.2 3.4 Milliamperes
Grids #2 & #4 Current 8 8 8
8 mA
Grids #2 & #4 Current 8 8 8 8 Milliamperes
Grid #1 Current 0.5 0.5 0.5
0.5 mA
Grid #1 Current 0.5 0.5 0.5 0.5 Milliampere
(not osciltating) is approximately 4500 micromhos under the following
4500 µS
(not osciltating) is approximately 4500 micromhos under the following
3 at
0 V
3 at 0 volts
2 & Fu } at
100 V
2 & Fu } at 100 volts
feedback of approximately 2 volts peak in the cathode circuit
2 V
feedback of approximately 2 volts peak in the cathode circuit.
MA X
5 mA
MA X 25/5"
grid toplate: (g3 to D) mBR. , . & . ¢ 4o ¢ « o o a ¢ o s o o o 0,
25 pF
grid toplate: (g3 to D) mBR. , . & . ¢ 4o ¢ « o o a ¢ o s o o o 0,25 puf
Oscillator grid to plate: (gL tO D) MBX. . v « o o o o o 2 o o o o » 0,
6 pF
Oscillator grid to plate: (gL tO D) MBX. . v « o o o o o 2 o o o o » 0,06 uuf
tP)e « ¢ o o ¢ o o o s o ¢ o +
3 pF
tP)e « ¢ o o ¢ o o o s o ¢ o + 3 puf.
(BC OF GC). 4 ¢ o o o o o ¢ o o oo s s s s s s o o s o
6.3 V
(BC OF GC). 4 ¢ o o o o o ¢ o o oo s s s s s s o o s o 6.3 volts
Maximum heater-cathode vOlta8g6 . . o« ¢« ¢ o « « o o o v o o ¢ « o = » o
90 V
Maximum heater-cathode vOlta8g6 . . o« ¢« ¢ o « « o o o v o o ¢ « o = » o 90 volts
Mumphtevoltageo ......‘.....'~..-;.o'_
300 V
Mumphtevoltageo ......‘.....'~..-;.o'_......300 v°lt5
Maximum grids #2 and #4 vOltAZE., . v.. v & ¢ « o o o o o « o » o o o »
100 V
Maximum grids #2 and #4 vOltAZE., . v.. v & ¢ « o o o o o « o » o o o » 100 vOlts
Maximum grids #2 and #k4 supply VOLtBEE . . v « ¢ « o « o « = &+ o « « o
300 V
Maximum grids #2 and #k4 supply VOLtBEE . . v « ¢ « o « o « = &+ o « « o 300 vOlts
Minimum negative ¢ grid #3 VOLLABEE. + o ¢ o « o o o o o o o o o o o o =
50 V
Minimum negative ¢ grid #3 VOLLABEE. + o ¢ o « o o o o o o o o o o o o =50 vOlts
Maximum positive dc grid #3 VOltBEe.v o o « o o o oo o o o o o o o «
0 V
Maximum positive dc grid #3 VOltBEe.v o o « o o o oo o o o o o o o « 0 volts
Maximum plate dissipation, . . . . P e
1 W
Maximum plate dissipation, . . . . P e 1.0 watts
Maximum grids #2 and #4 disaipe.tion.~. e s o o s 0 o s e e o e ees 1,
0 W
Maximum grids #2 and #4 disaipe.tion.~. e s o o s 0 o s e e o e ees 1,0 watts
Heater voltage, . . . . 6.3
6.3 V
Heater voltage, . . . . 6.3 6.3 volts
Heater current,
300 mA
Heater current, . . . . 300 ma
Plate voltage
100 V
Plate voltage . . . . . . 100 volts

Characteristic

Plate Resistance (Approx.) 0.5 0.8 0.5
0.8 ohm
Plate Resistance (Approx.) 0.5 0.8 0.5 0.8 Megohm

Data set 02

1950 Sylvania

Published operating points and test conditions from this source.

SECTION 1

Heptode

Application

Primary application
Pentagrid frequency converter

Data set 03

1953 RFT Rundfunk Technik

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

HeaterVoltageNominal
6.3 V
Nominal
HeaterCurrentNominal
300 mA
Nominal
Maximum Plate Voltage
300 V
Maximum Screen Voltage
100 V
Maximum Plate Dissipation
1 W

Characteristic

Transconductance
450 µS
Typical
Plate Resistance
1000000 ohm
Typical

Data set 04

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

Heater voltage
6.3 V
Heater current
300 mA
Plate voltage
300 V
Typical operating conditions
Plate current
3.33.53.33.5 mA
Typical operating conditions

Data set 05

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

Heptode

Other

Plate Voltage
250 V
Converter
Screen Voltage
100 V
Converter

Characteristic

Plate Resistance
1 Mohm
Converter
Conversion Transconductance
450 uS
Converter
Oscillator Amplification Factor
14
Oscillator
Oscillator Transconductance
4500 uS
Oscillator

Data set 06

1971 RCA HB3 Binder 5 of 7

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristics

Voltage
6.3 V
Published datasheet value; multiple values represent separate source-table limits or conditions.
Current
300 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid 83 to Al l Other Et ect codes lR-F Input) 9.5~ — published value 1
83
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid 83 to Al l Other Et ect codes lR-F Input) 9.5~ — published value 2
9.5
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid NI to Al l — published value 1
7
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid NI to Al l — published value 2
8
Published datasheet value; multiple values represent separate source-table limits or conditions.
Electrodes except Cathode
4.4
Published datasheet value; multiple values represent separate source-table limits or conditions.
Cathode h Grid aM5
5
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid 81 to Cathode — published value 1
81
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid 81 to Cathode — published value 2
26
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid #I to Cathode 6 Grid #5 — published value 1
6 pF
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid #I to Cathode 6 Grid #5 — published value 2
5 pF
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid #I to Cathode 6 Grid #5 — published value 3
3 pF
Published datasheet value; multiple values represent separate source-table limits or conditions.
Electrodes except Grid kl
5 pF
Published datasheet value; multiple values represent separate source-table limits or conditions.
Cathode and Grid 4'5 to Al l Other — published value 1
4
Published datasheet value; multiple values represent separate source-table limits or conditions.
Cathode and Grid 4'5 to Al l Other — published value 2
5
Published datasheet value; multiple values represent separate source-table limits or conditions.
El ect codes except Grid 1M1 — published value 1
1 pF
Published datasheet value; multiple values represent separate source-table limits or conditions.
El ect codes except Grid 1M1 — published value 2
14 pF
Published datasheet value; multiple values represent separate source-table limits or conditions.
f6SA7,Shell,Grid #5 — published value 1
5
Published datasheet value; multiple values represent separate source-table limits or conditions.
f6SA7,Shell,Grid #5 — published value 2
8
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 2 -Heater
2
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 3 -Plate
3
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 4 -Grids #2 d #4 — published value 1
4
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 4 -Grids #2 d #4 — published value 2
2
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 4 -Grids #2 d #4 — published value 3
4
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 5 -Grid #1 — published value 1
5
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 5 -Grid #1 — published value 2
1
Published datasheet value; multiple values represent separate source-table limits or conditions.
Ping 6SA7,Cathode — published value 1
6
Published datasheet value; multiple values represent separate source-table limits or conditions.
Ping 6SA7,Cathode — published value 2
0
Published datasheet value; multiple values represent separate source-table limits or conditions.
6SA7-GT/G,Cathode h
6
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid #5
5
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 7 -Heater
7
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 8 -Grid #3 — published value 1
8
Published datasheet value; multiple values represent separate source-table limits or conditions.
Pin 8 -Grid #3 — published value 2
3
Published datasheet value; multiple values represent separate source-table limits or conditions.

Other

Grid JFS to Plate — published value 1
0.13 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid JFS to Plate — published value 2
0.5 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid ~lS to Grid NI — published value 1
0 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid ~lS to Grid NI — published value 2
15 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid ~lS to Grid NI — published value 3
0.4 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid kl to Plate — published value 1
0.06 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.
Grid kl to Plate — published value 2
0.2 mA
Published datasheet value; multiple values represent separate source-table limits or conditions.