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1A4P Vacuum Tube New and Used

- Description
- Specifications
The 1A4P is a 4-pin sharp-cutoff pentode designed for radio frequency (RF) and intermediate frequency (IF) amplifier service in battery-operated radio receivers. It features a top grid cap for high-frequency isolation and operates on a 2.0V direct filament supply. RCA, Sylvania, GE, and Philco manufactured the 1A4P to RETMA specifications using ST-12 glass envelopes. It is functionally identical to the earlier 1A4, with the "P" designation indicating a later glass bulb style and production refinement.
Tube Function: Sharp-Cutoff RF/IF Pentode
Base Design: 4-Pin Standard with Top Cap (Control Grid)
Glass Shape: ST-12
Filament Power: 2.0 Volts DC
Filament Draw: 0.06 Amps
Maximum Plate Voltage: 180 Volts
Maximum Screen Grid Voltage: 67.5 Volts
Signal Strength (Mutual Conductance): 750 micromhos
Cathode Heating Method: Direct (Filament)