EL85

Output pentode rated for approximately 6 W anode dissipation, suitable for mobile-equipment RF amplification to about 120 MHz or conventional audio-frequency output service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: B9A
Socket code: B9A
Base pins: 9
Nominal heater: 6.3 V / 200 mA

Description

OUTPUT PENTODE Output pentode roted for 6W anode dissipation intended for use in mobile equipment as a r.f. amplifier at frequencies L8S up (0 120Mcls or as on a.f. output valve. H EATER Vh 6.3 V r, 200 mA

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: B9A
Socket code: B9A
Base pins: 9
Nominal heater voltage: 6.3 V
Nominal heater current: 200 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

B9A - 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

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 100000 Ω
Transconductance: 0.0032 S
Max plate dissipation: 6 W
Max screen dissipation: 1 W

Published Ferranti ratings and characteristics promoted from the supplied source.

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

1961 Ferranti Technical Handbook

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

Heater Voltage
6.3 V
Heater Current
200 mA
MaximumRFApplicationFrequency
120 MHz
RFAmplifier
Application
AF output

Data set 02

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

HeaterOrFilamentVoltage
6.3 V
HeaterOrFilamentCurrent
200 mA
PlateToGridCapacitanceMax
0.2 pF
Input Capacitance
4.3 pF
Output Capacitance
5.1 pF
Plate Voltage
250 V
Screen Voltage
250 V
Plate Current
24 mA
Screen Current
4.1 mA
Grid Voltage
-13.5 V
MaximumRFApplicationFrequency
120 MHz

Other

Power Output
2.5 W
ClassA
Power Output
6.8 W
PushPull;ClassAB

Data set 03

1967 Mullard Receiving Tubes for Maintenance

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

Output pentode roted for
6
Characteristic
up (
120 a
Characteristic
gm
3.1 mA
CHARACTERISTICS
ra
100
CHARACTERISTICS

Other

Va
250 V
OPERATING CONDITIONS AS SINGLE VALVE C LASS u A "
EL8S Output pentode rated for
6 W
OPERATING CONDITIONS AS SINGLE VALVE C LASS u A "
up to
120 a
OPERATING CONDITIONS AS SINGLE VALVE C LASS u A "
Va
250 V
OPERATING CONDITIONS FOR TWO VALV ES IN CLA SS u Rn
Vg•
250 V
OPERATING CONDITIONS FOR TWO VALV ES IN CLA SS u Rn
Va
300 V
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
Vg •
175 V
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
Vg,
30 V
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
Vg J
-60 V
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
Vg1
-100 V
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
Output pentode rated for
6 W
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
up to
120 a
R.F. OPERATING CONDITIONS FOR SINGLE VALVE, CLASS He"
VaIn) max
550 V
LIMITING VALUES
Va max
300 V
LIMITING VALUES
Vg
550 V
LIMITING VALUES
Vg
300 V
LIMITING VALUES
Vg
100 V
LIMITING VALUES
Vg1 ma x . (lg1 = +
1.3 ma
LIMITING VALUES
EL8S Output pentode rated for
6
LIMITING VALUES
up to
120 a
LIMITING VALUES
I.V o " Vg
250 V
LIMITING VALUES
2.Vo = Vg 2 = 200V
200
LIMITING VALUES