Sennheiser Set 820 Notice D'emploi page 27

Connecting the transmitter (charging unit)
The rear of the transmitter is
fitted with two audio inputs:
A socket (LINE) for connection
to the LINE OUT socket or the
headphone socket on your TV,
and a microphone socket (MIC).
Plug in one end of the connecting cable to the LINE OUT socket or the
headphone socket on your TV, and the other end to the LINE socket on the
transmitter.
If your TV does not have a headphone or RCA socket, you can use an
external microphone which is described in the section "Accessories".
Only use one of the two audio inputs on the transmitter (MIC or LINE).
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