• Country
• Great Britain (UK)

• Manufacturer / Brand
• Burndept Ltd. London

• Year
• 1927/1928

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 77424

• Number of Tubes
• 4

• Valves / Tubes
• S625 PM5X L525 or LL525 PM256

• Main principle
• TRF with regeneration; 2 AF stage(s)

• Tuned circuits
• 2 AM circuit(s)

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

• Power type and voltage
• Storage and/or dry batteries / 100 or 120 or 150 or 180 & 20 & GB & 6 Volt

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

• Material
• Wooden case

• from Radiomuseum.org
• Model: Screened Four Screengrid - Burndept Ltd. London

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

• Dimensions (WHD)
• 19 x 11.5 x 13 inch / 483 x 292 x 330 mm

• Notes
• Burndept Wireless Ltd., London (from Witt Brunham of Burnham & Co.) has manufactured a few early screen grid radios under the name of "Screened". They first used the double ended valve S625 but in the next year the single ended 220SG was used. See also Bowyer-Lowe Co. Ltd. in Letchworth for such sets.
  
  This model Screened Four has a mahogany case with sloping exposed mahogany control panel and hinged fielded panel lid. The early double-ended S625 screened grid valve from Marconi-Osram (designer H.J. Round, MO Valve Co. Ltd.) is visible in the top of the cabinet after lifting the lid. At the back there is an opening which leads to terminal board with 12 posts with clamping screws: Aerial, +/- Loudspeaker, +/- GB (Grid Bias), HIgh Tension 2 (HT2 +) with possible GB values for 100 (10.5), 120 (15), 150 (22.5) and 180 (30), High Tension 1 (HT1 +) and HT-, Heater 6 V +/-, Gram and Earth. There is a sticker with the mentioned valves including the Heater Resistors and the Grid Bias for the given HT2-values.

• Net weight (2.2 lb = 1 kg)
• 9.5 kg / 20 lb 14.8 oz (20.925 lb)

• Source of data
• Radio! Radio!

• Author
• Model page created by Konrad Birkner † 12.08.2014. See "Data change" for further contributors.

• Other Models

• Here you find 93 models, 61 with images and 28 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Burndept Ltd. London