2.
PREPARING THE TRANSMITTER
After removing the transmitter from its packaging, open the lid of the
battery compartment [4] by levering it off with a coin or a screwdriver,
as illustrated in Figure 2.1, and insert a 9V type PP3 battery, making
sure that the polarity is correct.
Close the compartment by putting the plastic lid removed earlier
back into place.
3.
SWITCHING ON AND TESTING THE BATTERY
To switch on the transmitter, move the ON/OFF switch [2] to the
intermediate position. At the same time, check that signalling lamp [3]
lights up for a short time; this means that the battery has been correctly
inserted and that is charged.
If the lamp [3] remains on, the battery is discharged and should be
immediately replaced with a new one; if the lamp does not light up,
check the polarity of the battery or replace it, since it is not longer
able to supply any energy whatsoever.
4.
PILOT TONE
The operation of this wireless microphone system is based on the
detection and identification of a specific signal, the so-called
"pilot tone", sent by the transmitter together with the carrier frequency.
The squelch circuit therefore only activates the receiver if the level of
the signal received by both aerials is higher than the threshold level
that has been set, and only if the pilot tone is detected.
This prevents rustling and other background noise generated by
unwanted signals picked up by the aerials from reaching the
broadcasting system.
5.
USING THE TRANSMITTER
After switching on the radio-microphone transmitter, make sure that
its receiver is hooked up to the signal being transmitted (refer to the
instructions of the receiver in this respect).
To enable the audio signal of the microphone capsule, move the ON/
OFF switch [2] to the "ON" position.
Adjust the sound level as required by means of the input volume
control of the mixer or amplifier to which the radio-microphone system
is connected. To mute the microphone capsule, move the switch [2]
to the intermediate position.
Once you have finished using the radio-microphone system, always
switch the transmitter off by moving the ON/OFF switch [2] to the
"OFF" position.
This will enable the battery to remain charged. If the transmitter is not
used for long periods of time, it is a good rule to remove the battery
from its compartment in order to avoid oxidising or leakage of acid
from the battery itself.
UHF WIRELESS SYSTEMS
Fig. 2.1
6.
TIPS
Following are a few tips for using the radio-microphone system to
your full satisfaction:
6.1 Always keep the efficiency of the battery inserted inside the
transmitter under control.
6.2 Always keep the squelch level of the receiver as low as possible,
compatibly with the operating conditions (operating range,
obstacles, charge of the transmitter battery).
6.3 Carry out a trial with the transmitter in the area concerned, in
order to check whether there are any skip areas. If necessary,
identify the best direction for the aerials of the receiver and
reposition it in a place that provides better reception.
6.4 During the inspection referred to under point 6.3, also check
whether there is any acoustic feedback (Larsen effect).
If there is, we recommend using one or more of the following
methods in order to eliminate it:
– positioning the loudspeakers so that they point in a different
direction;
– increasing the distance between the area where the
transmitter is being used and the closest loudspeakers;
– lowering the level of the volume of the broadcasting system.
7.
TECHNICAL SPECIFICATIONS
Carrier frequency
Pilot tone
Type of modulation
Audio-frequency response (± 3 dB)
Frequency stability
Rated deviation
RF output power
Harmonic distorsion
Dynamic range
Power supply
Power consumption
Typical operational duration (hours)
Dimensions
Weight
8.
LIST OF SPARE PARTS
CODE
DESCRIPTION
UM116
Complete microphone unit assembly
27/4384
Grilled head assembly
19/101
Switch
41/511-N
Push-button cover
27/4383-X(*)
Transmitter circuit assembly
41/479-N
Battery compartment lid
36/2129-NK
Pair of battery contact clamps
36/2130-NK
(*) Frequency.
5
UHF Range 433,05÷434,79 MHz
32,768 kHz
FM (F3E)
50÷15000 Hz
± 0,005% / 25°C
± 40 kHz at 1 sinusoidal kHz
8 mW
< 1% at rated deviation
100 dB
9V battery IEC 6LR61
< 30 mA
Ø 52 x 250 mm
210 g
6÷8