Lectrosonics UDR700, Инструкция по эксплуатации

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Encrypted Digital Wireless System
The insulated flexible galvanized steel cable antenna
supplied with the transmitter is cut to 1/4 wavelength of
the center of the frequency block (the frequency range)
of the transmitter. It is removable via an SMA connec­
tor. The SMA connector is a 50 Ohm RF port which can
also be connected directly to test equipment. Replace­
ment antennas are available in pre-cut lengths for
specific frequency blocks, or as a kit with instructions to
cut the antenna for any frequency block. Replacement
antenna is part AMM(xx) where “xx” indicates the
frequency block, i.e.. AMM27 for block 27. (See Acces­
sories Master Catalog, or visit www.lectrosonics.com.)
Adjustable Low Frequency Roll-Off Control
An 18 dB per octave Low Frequency Roll-off Control is
provided in the audio section, with the -3 dB point
adjustable from 35 Hz to 150 Hz. The actual roll-off
frequency will vary according to the low frequency
response of the mic capsule being used.
. .
Low Frequency Roll-off Adjustment
The low frequency roll-off control is used to reduce the
undesirable effects of very low frequency audio, such as
those produced by air conditioning systems, automobile
traffic and other sources. Excessive low frequency
content in the audio input can cause overload of the
program audio in recording applications. In sound
reinforcement systems, excessive low frequency
content can cause excessive power amplifier drain or
even damage to loudspeaker systems. A common
example is wind blowing across a microphone, causing
very high levels of low frequency audio (wind noise). By
rotating the roll-off control clockwise, the hinge point of
the roll-off is increased to reduce the level of low
frequencies. In low noise situations, such as a motion
picture production set indoors where environmental
noise is minimal, the control can be rotated counter­
clockwise to permit low frequency audio to be captured.
The Belt Clip
The belt clip may be removed for special applications by
removing the Belt Clip Attachement Screw.
WARNING: USE ONLY THE SCREW THAT IS
SUPPLIED.
The circuitry is tightly packed into this unit. A longer
screw will permanently damage the transmitter! Use
only Lectrosonics PN:28528 which is a Phillips head, 4­
40 x 3/16", FL100 screw.
UM700 Battery Installation
The transmitter is powered by a standard alkaline or
lithium 9 volt battery. Use alkaline or lithium batteries
for longest life. Standard zinc-carbon batteries marked
“heavy-duty” or “long-lasting” are not adequate. Ni­
cad or NiMH rechargeable batteries provide 1.5 hours
of operation, or less, and will run down quite abruptly.
Unless it is cold, alkaline batteries provide over 4.0
hours of operation. Lithium batteries can be used to
provide up to 7.5 hours. Care should be taken not to
leave a fully discharged lithium battery in the transmit­
ter, as swelling of the battery can make it difficult to
remove from the compartment. The battery status
circuitry is designed for the voltage drop over the life of
alkaline batteries.
To open the battery compartment, press outward on
the cover door in the direction of the arrow as shown in
the drawing. Only firm, sliding pressure is needed to
open and close the battery door. Swing the door open
and take note of the polarity marked inside showing the
location of the positive (+) and negative (-) terminals.
You can see the large and small contact holes inside
the battery compartment with the door open.
Insert the battery correctly and close the cover by
pressing the door closed and across, reversing the
opening procedure illustrated above. If the battery is
inserted incorrectly, the door will not close. Do not
force the door closed.
Swing the
door open
Press outward on the
battery door in this
direction
,
.
Belt Clip Attachment Screw location
Rio Rancho, NM 15