the infrared- and ultraviolet segments of the blended lamp of the Philips Biosol 11911/28 sunlamp could be used independently
Philips Biosol 11911/28 sunlamp
It was uncommon for a blended lamp to provide
individual use of its infrared- and ultraviolet
capabilities but the Philips Biosol 11911/28 sunlamp
was an exception. With this sunlamp the gas
discharge tube and the filament were indeed
mounted in the same glass bulb but their leads were
connected to a 3-pole socket. This allowed the
discharge tube to be ballasted either by the filament
in the bulb or by a separate ballast, mounted in the
base of the lamp.