A mixed light bulb looks almost identical to the shown mercury lamp, but can be connected to the voltage without a switch
A mixer lamp is a lamp that contains both a gas discharge tube filled with mercury vapor and a filament. The filament, an electrical resistor, serves as a displacement lamp for the discharge lamp so that it can be connected to the power supply without delay. The color spectrum of the fluorescent lamp is warmer than for a mercury lamp by the contribution of the filament.
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