551 BLUE
- First year: 1931
- Base: UY-Base, 5 Pins (USA, April 1927) (Codex=Fo) Top contact with a cap
- Filament: Vf 2.5 Volts / If 1.7 Ampere / Indirect / Parallel, (AC/DC) /
- Identical to: 551 = 35 = 35/51 = 51
- Tube type: Screen-grid Tetrode RF/IF-Stage Controlling (mu)
Published by:
dido