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Power - Pentode (NOT beam) (over 1000V 100W) ·Pentode

ACPT8

Marconi transmitting pentode designed for high-frequency power amplification and oscillator service. Aligned screen and control grids support RF performance, with forced-air cooling specified at high dissipation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
11 V / 16 A

Description

The ACPT8 is a transmitting pentode for high-frequency power-amplifier and oscillator service, with aligned screen and control grids and forced-air cooling at high dissipation.

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
11 V
Nominal heater current
16 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

Pentode

X-ray radiationInterelectrode capacitances
Transconductance
0.0065 S
Max plate voltage
4500 V
Max screen voltage
800 V
Max plate dissipation
750 W
Max screen dissipation
100 W

Published maximum ratings and characteristics audited; remaining useful numerical data retained in TUBE_SECTION_PARAMETER.

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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Published value [1]

    750

    750 W and giving useful output down to 9 metres.

  • Published value [2]

    9

    750 W and giving useful output down to 9 metres.

  • The screen and control grids are aligned, giving high : I -<§- +

    0.059

    The screen and control grids are aligned, giving high : I -<§- +0.059

  • are only applicable for use at wavelengths down to ANODE [1]

    5

    are only applicable for use at wavelengths down to ANODE 5-374CRS: 2756

  • are only applicable for use at wavelengths down to ANODE [2]

    -374

    are only applicable for use at wavelengths down to ANODE 5-374CRS: 2756

  • are only applicable for use at wavelengths down to ANODE [3]

    2756

    are only applicable for use at wavelengths down to ANODE 5-374CRS: 2756

  • ( [1]

    1 W

    (1) HF POWER AMPLIFIER Ve 800 800

  • ( [2]

    800 W

    (1) HF POWER AMPLIFIER Ve 800 800

  • ( [3]

    800 W

    (1) HF POWER AMPLIFIER Ve 800 800

  • Ia [1]

    550 W

    Ia 550 475 380 330 mA (3) HF POWER AMPLIFIER

  • Ia [2]

    475 W

    Ia 550 475 380 330 mA (3) HF POWER AMPLIFIER

  • Ia [3]

    380 W

    Ia 550 475 380 330 mA (3) HF POWER AMPLIFIER

  • Ia [4]

    330 W

    Ia 550 475 380 330 mA (3) HF POWER AMPLIFIER

  • Ia [5]

    3 W

    Ia 550 475 380 330 mA (3) HF POWER AMPLIFIER

  • Iy [1]

    120

    Iy 120 180 160 160 mA (Anode modulated, one valve, carrier conditions,

  • Iy [2]

    180

    Iy 120 180 160 160 mA (Anode modulated, one valve, carrier conditions,

  • Iy [3]

    160

    Iy 120 180 160 160 mA (Anode modulated, one valve, carrier conditions,

  • Iy [4]

    160

    Iy 120 180 160 160 mA (Anode modulated, one valve, carrier conditions,

  • (

    2 W

    (2) HF POWER AMPLIFIER

  • ( [1]

    4 W

    (4) HF POWER AMPLIFIER (5) HF POWER AMPLIFIER

  • ( [2]

    5 W

    (4) HF POWER AMPLIFIER (5) HF POWER AMPLIFIER

  • (a) Screen voltage obtained by means of a dropping resistance of (c) At crest of audio cycle with

    100 V

    (a) Screen voltage obtained by means of a dropping resistance of (c) At crest of audio cycle with 100% modulation.

  • Published value [1]

    30000

    30,000 from anode HT supply. (d) 100% modulation.

  • Published value [2]

    100

    30,000 from anode HT supply. (d) 100% modulation.