Annular gap (cylindrical body) electro-magnet No. 3, c..1898

Made:
1898-1900 in England
maker:
Oliver Joseph Lodge

Annular gap (cylindrical body) electro-magnet No. 3, assembled with polar gap approximately 19/16" to 1 1/4", part of Oliver Lodge’s microphone amplifier or relay, 1898 (British patent 9712 of 1898), a precursor of the moving-coil loudspeaker

Details

Category:
Radio Communication
Object Number:
1926-711
type:
electro magnet
credit:
Sir Oliver Lodge.