Wind up clock that can be used to switch radios on and off. The
time can be set at a 10 minute interval by means of small plug-in brass mounting pins.
1929, clock factory Müller & Co. in Mühlheim an der
Donau offered various models of their radio timer "Chronoradio",
a device in the shape of a round, shiny metal alarm
clock (ad opposite). The differences were in the
switching possibilities. Both battery operated and mains
radios could be switched on and off. In 1934, they
introduced a new type that could switch bigger currents. Five different types came on the market.
Three of them in a dark red metal case and two in a
Bakelite case. The differences mainly had to do with a
12-or 24-hour display and the ability to work with
bigger currents. This unit can switch devices up to
440 Watts DC and 220 Watts