• Country
• Great Britain (UK)

• Manufacturer / Brand
• Columbia Graphophone Co.; London

• Year
• 1929

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 221582

Click on the schematic thumbnail to request the schematic as a free document.

• Number of Tubes
• 6

• Valves / Tubes
• PM12 PM12 PM12 L210 P625 U5

• Main principle
• TRF without regeneration; 1 AF stage(s); Anode bend detection

• Tuned circuits
• 4 AM circuit(s)

• Wave bands
• Broadcast (MW) and Long Wave.

• Power type and voltage
• Alternating Current supply (AC)

• Loudspeaker
• - This model requires external speaker(s).

• Material
• Wooden case

• from Radiomuseum.org
• Model: 304 - Columbia Graphophone Co.;

• Shape
• Tablemodel, Box - most often with Lid (NOT slant panel).

• Notes
• The filaments of the first four valves in this radio are supplied from a metal rectifier. This supply is filtered by two high value (2000 µF) electrolytic capacitors and a choke. Provision is made for the use of a pentode in the output stage if desired.

• Mentioned in
• Wireless World 19/2/30 P197

• Author
• Model page created by Stuart Irwin. See "Data change" for further contributors.

• Other Models

• Here you find 51 models, 28 with images and 23 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Columbia Graphophone Co.; London