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7X7 Vacuum Tube New and Used

- Description
- Specifications
The 7X7 is a duo-diode triode vacuum tube designed for AM detection, automatic volume control (AVC), and audio voltage amplification stages in superheterodyne radio receivers. Featuring a 6.3V filament rating with a 300mA current draw, it utilizes an 8-pin lock-in (loctal) base in a glass envelope construction. Manufactured by companies including Sylvania, Philco, RCA, and GE, this tube was widely used in mid-century receiver chassis requiring combined detector and triode audio amplification functions.
Tube Type: Duo-Diode Triode
Base Type: Loctal / Lock-In (8-pin)
Envelope Style: Glass T-9
Filament Voltage: 6.3 V AC/DC
Filament Current: 0.3 A (300 mA)
Maximum Plate Voltage: 250 V (Triode)
Plate Dissipation: 1.0 W (Triode)
Amplification Factor (µ): 16
Transconductance: 1,900 µmhos
Primary Function: AM signal detection, AVC rectification, and audio voltage amplifier stage
Condition Options: New Old Stock (NOS) or Tested Used