931 Beckman Electrometer Tetrode Sylvania 1229 Type 32 Derivative Vacuum Tube

This is an original 931 Beckman Electrometer Tetrode replacement tube originally a Sylvania 1229 derivative based on the Type 32 vacuum tube and selected for lowest grid current with additional shielding added. This is a rare, hard to find, classic four pin tube. It is useful in many older instruments, special circuits, VTVMs, old time receivers, transmitters and transcievers. Useful for antique radio, instrument restoration projects or to set up a private vacuum tube museum.

---

HISTORICAL TECHNICAL COLLECTIBLE Features: • 931 Beckman Electrometer Tube • MFG: Sylvania - 1229 Tetrode Derivative • Low grid current selection • Electrometer instrument applications • Filament: 2 V, 60 mA • Plate: 180 VDCmax • Base: 4-pin • Discontinued Collectible Tube • High quality Made in USA Notes: • Unused • Price: $20 • One available • Without box • S/H included within continental US

---

• Only one item available unless otherwise indicated • Click the credit card pictures left to order • • E-Mails always answered unless return e-mail is blocked