Sennheiser 500 Series Headphones User Manual


 
Cleaning the devices
30
If a problem occurs ...
EM 500
Problem Possible cause Possible solution
Receiver cannot be oper-
ated, “Locked” appears
on the display panel
Lock mode is activated Deactivate the lock mode (see page 22).
No operation indication No mains connection Check the connections of the mains unit.
No RF signal Transmitter and receiver are not on the
same channel
Set the transmitter and receiver to the same
channel. To do so, use the synchronization
function (see page 21).
Transmitter is out of range Check the squelch threshold setting
(see page 26).
Reduce the distance between transmitter and
receiving antennas.
RF signal available,
no audio signal,
MUTE” appears on the
display panel
If “TX Mute” additionally appears on the
display panel:
transmitter is muted (“MUTE”)
or
transmitter doesn’t transmit a pilot tone
Cancel the muting (see page 23).
Switch the pilot tone transmission on the trans-
mitter on (see
page 28
).
Switch the pilot tone evaluation on the receiver
off (see page 27).
Receiver’s squelch threshold is adjusted
too high
Reduce the squelch threshold (see page26).
Reposition the antennas.
Audio signal has a high
level of background noise
Transmitter sensitivity is adjusted too
low/high
Adjust the transmitter sensitivity correctly
(“Sensitivity”, see page 28).
Audio signal is distorted Transmitter sensitivity is adjusted too
high
Adjust the transmitter sensitivity correctly
(“Sensitivity”, see page 28).
Receiver’s audio output level is adjusted
too high
Reduce the audio output level
(“AF Out”, see page 27).
No access to a certain
channel
During scanning, an RF signal has been
detected on this channel and the channel
has been locked
Set the transmitter operating on this channel to
a different channel and redo the frequency
preset scan (see page 27).
During scanning, a transmitter of your
system operating on this channel has
not been switched off
Switch the transmitter off and redo the
frequency preset scan (see page 27).
None of the diversity
displays I or II appears on
the display panel
Receiver’s squelch threshold is adjusted
too high
Reduce the squelch threshold (see page26).
Transmitter’s RF signal is too weak Increase the transmission power of the
transmitter.
Reduce the distance between transmitter and
receiver.
Antennas are not connected correctly Check the antenna cables or the antennas.
During the soundcheck,
only one diversity display
(I or II) appears on the
display panel
One of the antennas is not connected
correctly
Check the antenna cable or the antenna.
Antennas are not optimally positioned Reposition the antennas.