- Item type
- Object
- Provenance
- Presented by the Marconi Corporation.
- Primary inscriptions
- "OSRAM / G.E.C. / MADE IN / ENGLAND / R.4" stamped on one side of exterior surface of bulb. "VALVE / WIRELESS RECEIVING NO. R.4 / PATT. NO.4411 / A.7953" stamped on other side of exterior surface of bulb.
- Object type
- Radio valve
- Dimensions
- Height: 90mm Width: 80mm Depth: 50mm
- Inventory No
- 59017
- Accession Number
- 2004-9/196
Description
Osram-GEC Soft Triode Radio Valve Type R4, with bulb-shaped glass exterior, brass fittings and a teak? mounting. With cylindrical anode threaded by helical grid with an interior single-strand wire filament, made of tungsten. In use filament would burn brightly similarly to a light bulb.
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