TubeDatabase
  • Tubes
  • Testers
  • Companies
  • Submit
  • About

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

Other (3,257 tube types), Pre (2,314 tube types), Power (1,030 tube types), Rectifier (740 tube types)
DisclaimerSubmit a tube

Tube-number record

HL.21/DD

0 archive entries

BrandMazda
ClassBattery Double Diode Triode
Base5-pin

Construction

Primary TypeMulti-section
EnvelopeMetallised
SectionsTriode and two independent diodes

Filament / Heater

Absolute Maximum Ratings

Plate Voltage150 V

Audio Performance

Key Features
  • Double diode triode for battery operated receivers
  • Independent sections
  • Metallised bulb

Typical Operation

ModePlate VGm (µmhos)Rp (Ω)µPlate mA
Triode Section100 V15002100032—

Application Notes

Detection, automatic volume control, and audio frequency amplification. Diode at Pin 2 for AVC, Diode at Pin 5 for detection. AVC delay voltage approximately 1.0V.

Datasheets

Datasheet: HL21DD.pdf

Download PDF
Loading datasheet...

Datasheets courtesy of Frank Philipse via Frank's Electron Tube Data Sheets.

Filters

0 tubes found

Manufacturers

Brands

    0 results