Ondolina 28 nouveau modèle

• This is the first SBR radio where the tubes are not visible on the outside.
• The retail price is without the tubes.
• There are 3 models Ondolina 28 known to exist:
  • Generation 1: has a feedback¹ regulator, no volume switch, and the switch for the scale lamps is just under the lid;
  • Generation 2: has a feedback¹ regulator, has a volume switch, and initially the swith for the scale lamps is still just under the lid, then later it is on the frontpanel;
  • Nouveau modèle: has a feedback¹ regulator and volume regulator. The switch for the scale lamps is on the frontpanel, jack for a pick-up at the back.
• All generations are fed via connectors on the backpanel with a 4V and a 120V (storage) battery.
• A separate internal battery for negative grid voltage is always present, even when fed with a power supply.
• There is an alternative tubeset: HL410, 2x L410, P425.
• The radio could be used with a M30 power supply, but also with a M35 power supply when it was converted to be used with a Réseau² tubeset E430, E409 or E415, E415, B403 or B405.

¹ Feedback = reaction (regenerative principle).
² Réseau tubes: from the French word "Réseau" = powergrid. Tubes that can be heated with AC current in contrast with battery tubes that are heated with DC current.

In questo link sono elencati 733 modelli, di cui 680 con immagini e 416 con schemi.
Elenco delle radio e altri apparecchi della SBR Société Belge Radio-Electrique, Bruxelles