2 Safety Notes
The units (receiver and power supply unit) correspond
to all required directives of the EU and are therefore
WARNING The power supply unit is supplied with
hazardous mains voltage (230 V~).
Leave servicing to skilled personnel
only. Inexpert handling may cause an
electric shock hazard.
Please observe the following items in any case:
The units are suitable for indoor use only. Protect
them against dripping water and splash water, high
air humidity, and heat (admissible ambient tempera-
ture range 0 – 40 °C).
Do not operate the receiver and immediately discon-
nect the power supply unit from the mains
1. in case of visible damage to the units or to the
2. if a defect might have occurred after a unit was
dropped or suffered a similar accident,
3. if malfunctions occur.
In any case the units must be repaired by skilled per-
A damaged mains cable of the power supply unit
must be replaced by the manufacturer or skilled per-
Never pull the mains cable for disconnecting the
mains plug of the power supply unit from the socket,
always seize the plug.
For cleaning only use a dry, soft cloth; never use
water or chemicals.
No guarantee claims for the units and no liability for
any resulting personal damage or material damage
will be accepted if the units are used for other pur-
poses than originally intended, if they are not cor-
rectly connected, operated, or not repaired in an
If the units are to be put out of operation de -
finitively, take them to a local recycling plant
for a disposal which is not harmful to the envi-
Defective rechargeable batteries do not belong in the
household rubbish; always take them to a special
waste disposal (e. g. collecting container at your
3 Applications and Accessories
Together with two matching transmitters from JTS, the
dual multifrequency receiver US-903DC PRO / 2 makes
up a wireless audio transmission system. The wireless
transmission of music or speech to the audio system
ensures the musicianʼs freedom of movement during
the performance. The transmission range depends on
the local conditions and can reach to a maximum of
The receiver operates with "diversity" technique:
The transmission signal is received by two antennas
placed at a distance from each other. The electronic
system selects the signal of the better quality and
pass es it on to the inputs of the receiving units.
For the reception four transmission groups (A – D)
with 16 transmission channels each are available,
i. e. altogether 64 factory-set transmission channels.
These channels in the UHF range of 740 – 764 MHz
can be selected as desired.
The unit is supplied with four rechargeable nickel
metal hydride batteries (1300 mAh) which can be used
for power supply of two transmitters and which can be
conveniently charged via the integrated charging unit.
The following transmitters from the product range
of JTS can be used together with the receiver
US-903DC PRO / 2:
MH-8800G / 2 order no. 25.2950
dynamic hand-held microphone with integrated multi -
PT-920BG / 2 order no. 25.2960
multifrequency pocket transmitter with Lavalier micro-
To increase the range and the interference immunity,
two antenna amplifiers UB-900 / 2 (order no. 15.0750)
available as accessories can be used instead of the
antennas supplied. The amplifiers are supplied with
power via the antenna jacks of the receiver.
When using several receivers in the audio system, the
antenna splitter UA-900 (order no. 15.0610) can be
used. It will also supply the power for a maximum of
4 Rack Mounting
The US-903DC PRO / 2 is provided as a table top unit
or for installation into a rack for units with a width of
482 mm (19"). For the rack installation unscrew the
four feet and screw the two supplied mounting brack-
ets (12) with two screws each to the front at the left
and right sides of the housing.