Sennheiser IS 150 Instructions For Use Manual page 17

Level control of the transmitter
Adjust the volume of your hi-fi system or television set to a middle position.
The TI 150 / TI 300 transmitter features an automatic modulation control
which prevents overmodulation.
Putting the receiver into operation
Insert the BA 151 accuplug into compartment
Take special note of the instructions on accuplug
operation on pages 20/21 of this manual!
(NB: The BA 151 accuplug must be charged for 24 hours before first use!)
Switching on the receiver
Use control to switch on the receiver and adjust the volume. An efficient
volume compression system avoids the necessity of frequent volume adjustments.
It reproduces quiet sounds slightly louder and loud sounds slightly quieter.
Adjusting your hi-fi system
Read the instruction manual of your hi-fi system or television set to find out
whether the volume control also works for the headphone socket, or whether
this socket has a separate volume control. The manual will also tell you how
to turn off the main loudspeakers.
in the receiver.
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