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7495

Rugged all-glass beam tetrode for VHF amplifier and driver applications, with construction emphasizing low catastrophic failure rate, heater-switching endurance, and low heater-cathode leakage.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: B9A
Base pins: 9
Nominal heater: 6 V / 750 mA

Description

The 7495 is a nine pin all glass construction hean tetrcde for use in V.H.F. amplifier and driver applications. The use of a special rug;ed clectrode constructicn namufactured by means of semi-automatic assembly techniques contributes to a low catastrophic failure rate. The cathode sleeve is made of a special alloy to inhi®it the growth of cathode interface resistance during long periods of operation under cut~cff conditions and the pure tungsten heater has been desigmed to withstend frequent heater switching (see note). In gddition, the heater cathode construction and materials ensure very low levels of leskage. The glass base and envelope strain patterns are tightly controlled

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: 6 V
Nominal heater current: 750 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

1 physical section, each with unique specifications.

Section 1

Beam Power

X-ray radiationInterelectrode capacitances

Transconductance: 0.007 S
Amplification factor: 16
Max plate voltage: 300 V
Max screen voltage: 250 V
Max plate dissipation: 12 W
Max screen dissipation: 2 W

Primary electrical section; identical repeated sections compressed where applicable.

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

Beam Power

Characteristic

noninal value: heater-cathode voltage 240V r.o.s: applied voltages
240 V
noninal value: heater-cathode voltage 240V r.o.s: applied voltages
Voltage (ac or dec) 6.0 volts
6 V
Voltage (ac or dec) 6.0 volts
Current 0.75 amps
750 mA
Current 0.75 amps
Heater negative with respect to cathode eevcsvoresae. 100 vOlts
100 V
Heater negative with respect to cathode eevcsvoresae. 100 vOlts
Heater positive with respect to cathode .sveecvsessssss 100 volts
100 V
Heater positive with respect to cathode .sveecvsessssss 100 volts
Moximum anode dissipation .ooseescocccossscenccocscssoses 12 Watts
12 W
Moximum anode dissipation .ooseescocccossscenccocscssoses 12 Watts
Anode current 33 45 57 mA
57 mA
Anode current 33 45 57 mA
Sereen current - - 7.0 mA
7 mA
Sereen current - - 7.0 mA
Mutual conductance 5.6 7.0 9.0 mA/V
9 mA
Mutual conductance 5.6 7.0 9.0 mA/V
Anode current at V,g1 = -15V 15 mA
15 mA
Anode current at V,g1 = -15V 15 mA

Other

Maximum anode voltage (T,50) wececcaooesocnccoscassnasans 500 volts
500 V
Maximum anode voltage (T,50) wececcaooesocnccoscassnasans 500 volts
Maximum anode VOLtagE seecescevasscssesesncscnacansncsose 300 VOlts
300 V
Maximum anode VOLtagE seecescevasscssesesncscnacansncsose 300 VOlts
Maximum screen voltage (IgZ“O) teoseessscassascsasessesss 500 vOlts
500 V
Maximum screen voltage (IgZ“O) teoseessscassascsasessesss 500 vOlts
Maximum screen VOLtafe sseessescoscosasocscnasacsanaonas . 250 volts
250 V
Maximum screen VOLtafe sseessescoscosasocscnasacsanaonas . 250 volts