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Tube Database (7,341 tube types · 1,270 archive entries)

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Tube-number record

QB 3/500

0 archive entries

BrandPhilips
ClassTransmitting Screen-Grid Tube

Construction

Primary TypeTetrode
EnvelopeGlass
Sections1

Filament / Heater

MaterialTungsten

Absolute Maximum Ratings

Plate Voltage3000 V
Plate Dissipation350 W
Grid 2 Voltage800 V

Audio Performance

Key Features
  • No neutralizing required
  • Short wave HF amplifier
  • Low excitation power

Typical Operation

ModePlate VGm (µmhos)Rp (Ω)µPlate mA
Telegraphy (HF Amplifier)3000 V2200—7.5135 mA
Telegraphy (HF Amplifier)3000 V——7.5—
Telegraphy (HF Amplifier)3000 V——7.5—

Application Notes

Specifically designed for HF amplifier use, especially on short waves. The screen grid allows operation without neutralization. Compatible with QB 2/75 or TC 1/75 as driver stages.

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    Telegraphy (HF Amplifier)3000 V——7.5—