7492

Rugged long-life double triode with independent sections for RF and computer applications, designed for low failure rate, frequent heater switching, and stable cutoff operation.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: -
Socket code: B9A
Base pins: 9
Nominal heater: 12.6 V / 150 mA

Description

The 7492 is a nine pin, all glass construction double tricde with independent sections for use in both R,F and computor applications, The use of a gpecial rugied electrode construction manufactured by means of semi-autonatic assembly techniques contributes to a low catastrophic failure rate, The cathcde sleeve is rade of a special alloy to inhibit the growth of cathode interface resistance during long periods of operction under cut-cof'f conditions and the pure tungsten heater has been designed to withstand frequent heater switching (seec ncte), In addition the heater-cathode construction and rnnterials ensure very low levels of lezkage throughout life.

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: 12.6 V
Nominal heater current: 150 mA
Parallel heater voltage: 6.3 V
Parallel heater current: 300 mA
Series capable: Yes

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

Transconductance: 0.0055 S
Amplification factor: 60
Max plate voltage: 380 V
Max plate dissipation: 2.8 W
Max cathode current: 22 mA

Primary electrical section; identical repeated sections compressed where applicable.

Section 2

Triode

X-ray radiationInterelectrode capacitances

Transconductance: 0.0055 S
Amplification factor: 60
Max plate voltage: 380 V
Max plate dissipation: 2.8 W
Max cathode current: 22 mA

Second physical triode section; electrically identical twin section.

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

1954 STC Brimar

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

voltage 120% of nominal volue: heater-cathode voltage 240V r.m,s:
240 V
voltage 120% of nominal volue: heater-cathode voltage 240V r.m,s:
Voltage {ac or dc) 12.6 6.3 volts
6.3 V
Voltage {ac or dc) 12.6 6.3 volts
Heater negative with respect to cathode............. 100 vOlts
100 V
Heater negative with respect to cathode............. 100 vOlts
Anode current 7 10 14 mA
14 mA
Anode current 7 10 14 mA
Unbalance between anode current of sections - 3.2 mA
3.2 mA
Unbalance between anode current of sections - 3.2 mA
fnode current at V., = = 20V 10 WA
20 V
fnode current at V., = = 20V 10 WA

Other

Maximum anode dissipation (Bach SECtion) seseeessersnoeeross 2,8 watts
2.8 W
Maximum anode dissipation (Bach SECtion) seseeessersnoeeross 2,8 watts