• Country
• Switzerland

• Manufacturer / Brand
• Hofrela, Hochfrequenzlaboratorium; Zürich, ab 1938 Grenchen

• Year
• 1943/1944

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 12078

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

• Number of Tubes
• 6

• Valves / Tubes
• ECH21 EF22 EF22 EBL21 EM4 AZ21

• Main principle
• Superheterodyne (common); ZF/IF 468 kHz

• Tuned circuits
• 6 AM circuit(s)

• Wave bands
• Broadcast, Long Wave and Short Wave.

• Power type and voltage
• Alternating Current supply (AC) / 110-250 Volt

• Loudspeaker
• Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil)

• Material
• Wooden case

• from Radiomuseum.org
• Model: 644 - Hofrela,

• Dimensions (WHD)
• 515 x 300 x 245 mm / 20.3 x 11.8 x 9.6 inch

• Price in first year of sale
• 495.00 SFr

• External source of data
• E. Erb 3-907007-36-0

• Source of data
• Radiokatalog Band 2, Ernst Erb

• Circuit diagram reference
• Thali-Schemasammlung und Tungsram-Röhrenbestückung.

• Picture reference
• Das Modell ist im «Radiokatalog» (Erb) abgebildet.

• Other Models

• Here you find 5 models, 5 with images and 5 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Hofrela, Hochfrequenzlaboratorium; Zürich, ab 1938 Grenchen