• Country
• Belgium

• Manufacturer / Brand
• SBR Société Belge Radio-Electrique, Bruxelles

• Year
• 1930

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 167522

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

• Number of Tubes
• 5

• Valves / Tubes
• A441N A442 A425 A415 B443

• Number of Transistors

• Semiconductors
• Tr.Gl.=Metal-rectif. Metal-rectifier

• Main principle
• Superheterodyne (common); 2 AF stage(s)

• Tuned circuits
• 5 AM circuit(s)

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

• Power type and voltage
• Alternating Current supply (AC) / 110; 130; 220 Volt

• Loudspeaker
• Magnetic loudspeaker (reed) generic. / Ø 25 cm = 9.8 inch

• Material
• Wooden case

• from Radiomuseum.org
• Model: Super Ondolina 552 [AC] - SBR Société Belge Radio-

• Shape
• Tablemodel, high profile (upright - NOT Cathedral nor decorative).

• Dimensions (WHD)
• 390 x 530 x 310 mm / 15.4 x 20.9 x 12.2 inch

• Notes
• • Internally, the radio is divided into 2 sections: the radio in the bottom half and the power supply in the top half of the housing.
  • In case of the batteries version, the power supply section is left empty to make room for the (storage) batteries. This version has a control voltmeter with a push button on the left side for the filaments.
  • The AC mains version has an "Oxymétal"¹ rectifier. There is a rheostat, a push button and a voltmeter on the primary side of the mains transformer to compensate for voltage changes and a current regulator to keep the filament current constant.
  • The DC mains 110V version and the DC mains 220V version have an internal resistor block to adjust to the mains voltage and a rheostat with a push button and a voltmeter to compensate for voltage changes; also a current regulator to keep the filament current constant.
  • There is a tone control on the backside.
  • There is an alternative tubeset from Dario: R81 , R78 , R81 , R76 , R79.
  • All versions of this radio still need an internal 15V negative grid voltage battery ("C" battery).
  • This radio was delivered with a loop antenna 552.
  • The soffit lamp on the back of the power supply is a current regulator.

  ¹ "Oxymétal" (copper oxyd) rectifier.

  User instruction for tuning:

  • The left scale and its button determines the oscillator frequency also dependend on the position of the band switch at center panel. This oscillator frequency defines the received frequency.
  • The right scale and its button tunes the loop-antenna. This circuit is not very selective.
  • The sequence for finding a broadcast is 1) set the volume to maximum; 2) tune the oscillator to receive a carrier with sound; 3) tune the antenna to maximize the sound level; 4) reduce volume to acceptable level.  

  User instruction for tube filament stabilisation: There are 2 trimmers on the backpanel of the radio chassis. The right one (VR2 on schematic) is to bring the total filament current through the barretter up to 0,6A to have it functioning correctly. The left one (VR1) is to bring the voltage drop in the barretter within its limits defined by the manufacturer.

  Attention: Never remove a tube from its socket while the radio is working! This will overload the other filaments. The barretter system only works with a full tube complement.

• Price in first year of sale
• 3,500.00 BFr

• Author
• Model page created by Georges Van Campenhout † 28.4.22. See "Data change" for further contributors.

• Other Models

• Here you find 718 models, 666 with images and 393 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from SBR Société Belge Radio-Electrique, Bruxelles