QY4500A

Forced-air-cooled directly heated VHF power tetrode for Class-C RF amplification or oscillation and Class-B television service. Designed for substantial broadcast-frequency output.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: -
Base pins: -
Nominal heater: 5 V / 13.5 A

Description

The Mullard QY4500A is a forced-air-cooled directly heated VHF power tetrode for Class C RF amplification/oscillation and Class B television service.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: -
Base pins: -
Nominal heater voltage: 5 V
Nominal heater current: 13.5 A
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

Tetrode

X-ray radiationInterelectrode capacitances

Transconductance: 0.005 S
Max plate voltage: 4000 V
Max screen voltage: 500 V
Max plate dissipation: 500 W

Forced-air-cooled directly heated VHF power tetrode for Class C RF amplification/oscillation and Class B television service.

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

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristics

Heater/Filament Voltage
5 V
Heater/Filament Current
13.5 A
Transconductance
5000 uS
RepresentativeSpecifiedOperatingPoint
Input Capacitance
12.8 pF
Output Capacitance
5.6 pF
Plate-Grid Capacitance
0.05 pF

Other

Maximum Operating Frequency
220 MHz
FullOrSpecifiedRatings
Maximum Plate Voltage
4000 V
Maximum Screen Voltage
500 V
Maximum Plate Dissipation
500 W
RF Output Power
930 W
RepresentativePublishedOperatingPoint
RF Output Power
630 W
RepresentativePublishedOperatingPoint
Television Peak Output Power
1200 W
RepresentativePublishedOperatingPoint
Plate Voltage
4000 V
ClassC; 110MHz
Plate Current
315 mA
ClassC; 110MHz
RF Output Power
930 W
ClassC; 110MHz
Plate Voltage
3000 V
ClassC; 186MHz
RF Output Power
630 W
ClassC; 186MHz
Television Output Power
1200 W
ClassB; PushPull; Television; 220MHz