Current record mode: basic


530 of 655 records      previous / next

Marconi-Osram Radio Valve Type MPT4, by Marconi Company, London, Late 1920s

Inventory Number: 84752

84752-1t 84752-2t

Date: Late 1920s

Maker Details: Signed by Marconi-Osram Valve Co. Ltd.

Inscription: "Marconi / Valve / B.V.A." printed on sticker attached to exterior surface of bulb. "MADE IN ENGLAND / T / MPT / 4 / PATENTED" printed on top exterior surface of bulb. "MOV CO LTD" printed on underside of base.

Size: 130 mm in overall length (including base pins)

Materials: Glass, plastic?, steel, assorted metals.


Marconi-Osram Radio Valve (or Tube) Type MPT4 with mostly silvered glass balloon envelope, polished black plastic? base and five steel base pins. Cathode is a flattened tube and the two inner grids are shaped to have a central bulge and then flatten towards the support rods. Grid three is a open wire helix near to the anode cylinder and far away from the inner grids.

530 of 655 records      previous / next

Record mode: Basic | Medium Images | Large Images | Documents (3)