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L I M I T I N G /

C O M P R E S S I O N

Rear Panel Controls and Connections     3

1. DC INPUT - Connect the supplied AC Adapter to this
connector.  Secure AC Adapter DC cable with the
adjacent rear panel strain relief.

2. POWER ON/OFF Switch - Set this switch to the ‘ON’
position to operate the FMC 1000.

3. RF OUTPUT - This is the modulator output.

4. LIMITING/COMPRESSION SWITCH - This switch
selects the operation of the limiter.  Select the proper,
or desired, setting according to the following criteria:

“OFF” - For audio sources with limiting and/or compres-
sion already applied.  This setting bypasses the limiting
circuitry of the FMC 1000.  With the audio source
connected, adjust the INPUT LEVEL control to a setting
at or just below the point where the (OVER) MODULA-
TION indicators light on audio peaks.

“L” - For most types of audio sources and listening
environments.  This setting provides automatic limiting
on audio peaks to prevent loud bursts and to avoid
over modulation conditions which can cause distorted
audio at the receiver.  With the audio source con-
nected, (for example, the output of a public address
amplifier with a person speaking at a normal level into
the microphone), adjust the INPUT LEVEL control to a
setting at the point where the (OVER) MODULATION
indicators light on audio peaks.

“C+L” - For audio sources that contain relatively low
audio levels combined with relatively high audio levels
as might be encountered when the audio output from a
public address amplifier contains audio from multiple
microphones with different persons speaking.   This
setting provides automatic increasing of the low level
audio passages combined with limiting on voice peaks.
This type of audio processing can sometimes aid
intelligibility for a person receiving the signal while
located in a relatively noisy audio environment.  With
the audio source connected, and the weaker audio
levels active, adjust the INPUT LEVEL control to a
setting at or just below the point where the (OVER)
MODULATION indicators light on audio peaks.

5. LEFT AUDIO INPUT - Connect monaural audio input
signals to the appropriate unbalanced or balanced
LEFT AUDIO INPUT connector.  For monaural input,
program the FMC 1000 to display ‘MONO’.  See Item 5;
'TUNE 

 / 

 Buttons' in the ‘Front Panel Controls and

Indicators' section of this manual.

For stereo input, connect an unbalanced line level left
channel stereo audio signal to the phono connector or
connect a balanced line level left channel stereo audio
signal to the 3-pin female XLR connector.  The unbal-
anced phono style input and the XLR balanced input
on a given input (Left or Right) are each always active,
so audio will be fed from whichever input is being used.
Do not attempt to connect signals to both the
unbalanced and balanced connectors on a given
input (Left or Right).
  All inputs can be considered high
impedance (>20K Ohm).  The shield connection at pin
1 of the XLR connector can be conveniently connected
to ground (GROUND LIFT = ‘OFF’) or lifted from ground
(GROUND LIFT = ‘ON’) to eliminate hum or noise as
required.  For stereo input, program the FMC 1000 to
display ‘STEREO’.  See ‘Front Panel Controls and
Indicators: See Item 5;  'TUNE 

 / 

 Buttons' in the

‘Front Panel Controls and Indicators' section of this
manual.

6. GROUND LIFT Switch - Set to the ‘OFF’ position to
connect pin 1 of both LEFT and RIGHT XLR connectors
to ground.  Set to the ‘ON’ position to disconnect both
XLR connectors from ground.

7. RIGHT AUDIO INPUT -  For stereo input, connect an
unbalanced line level right channel stereo audio signal
to the phono connector or connect a balanced line
level right channel stereo audio signal to the 3-pin
female XLR connector.  Never connect signals to both
the unbalanced and balanced connectors on a given
input (Left or Right).    The shield connection at pin 1 of
the XLR connector can be conveniently connected to
ground (GROUND LIFT = ‘OFF’) or lifted from ground
(GROUND LIFT = ‘ON’) to eliminate hum or noise as
required.  For stereo input, program the FMC 1000 to
display ‘STEREO’.  See Item 5;  'TUNE 

 / 

 Buttons' in

the ‘Front Panel Controls and Indicators' section of
this manual.
Connect a monaural audio signal to the appropriate
LEFT AUDIO INPUT connector.  See Item 5: 'LEFT
AUDIO INPUT', on this page.

8. Access Hole for RF OUTPUT Level Adjustment -
The RF output level can be reduced to a value approxi-
mately 10 dB below the nominal level by adjustment of
the potentiometer.  The potentiometer is tunable
through the access hole.  Use a small straight-slot type
screwdriver to adjust the potentiometer, if adjustment  is
necessary.  Counterclockwise rotation of the potentiom-
eter decreases the output level.

         

      1           2            3         8       4                                                                               5                 6                  7

Summary of Contents for FMC 1000

Page 1: ...Instruction Manual FMC 1000 FM STEREO MODULATOR with Limiter and Compression is a registered trademark of the R L Drake Company Copyright 2002 R L Drake Co P N 3852433E 2 2002 Printed in the U S A ...

Page 2: ...uick stops excessive force and uneven surfaces may cause the product and cart combination to overturn The lightning flash with arrow head symbol within an equilateral triangle is intended to alert the user to the presence of uninsulated dangerous voltage within the product s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons The exclamation point within...

Page 3: ...ble system is grounded so as to provide some protection against voltage surges and built up static charges Article 810 of the National Electrical Code ANSI NFPA 70 provides informationwithregardtopropergroundingofthemastandsupportingstructure grounding of the lead in wire to an antenna discharge unit size of grounding conductors location of antenna discharge unit connection to grounding electrodes...

Page 4: ...iv This page left intentionally blank ...

Page 5: ... Please carefully read the Instruction Manual for proper installation and usage Caution Statements Important Safety Instructions Table of Contents Specifications Options and Accessories Introduction General Description Front Panel Controls and Indicators Rear Panel Controls and Connections Installation Setup and Operation Service Information If You Need To Call For Help Warranty ii iii v vi 1 2 3 ...

Page 6: ...A Phono input 20K Ohm input impedance balanced 10 to 10 dBu manual gain adjustment with front panel modulation indicators 20K Ohm input impedance balanced 16 to 4 dBu manual gain adjustment with front panel modulation indicators 20 Hz to 15 kHz 3 dB referenced to a standard 75 µSec pre emphasis curve Less than 0 25 typical 12 VDC 250 mA regulated by supplied wall AC Adapter 19 W x 1 75 H x 6 25 D ...

Page 7: ...rovided for the XLR connectors Full transmitter deviation with monaural audio input is provided by programming the unit for MONO and connecting the audio signal input to the appropriate Left Audio Input connector A rear panel Limiting Compression switch permits setting no limiting limiting only or limiting and compression operation A front panel Input Level control permits adjusting the audio inpu...

Page 8: ...l LIMITING COMPRESSION switch see rear panel Item 4 is set to OFF With the switch set for either the L or C L position these indicators will light on audio signal peaks as the limiter is activated at full modula tion Also see rear panel Item 4 for additional hints for proper setting of the LIMITING COMPRESSION switch for a given type of audio source Set the INPUT LEVEL control at or just below the...

Page 9: ...ural audio input signals to the appropriate unbalanced or balanced LEFT AUDIO INPUT connector For monaural input program the FMC 1000 to display MONO See Item 5 TUNE Buttons in the Front Panel Controls and Indicators section of this manual For stereo input connect an unbalanced line level left channel stereo audio signal to the phono connector or connect a balanced line level left channel stereo a...

Page 10: ...s hole The access hole is located adjacent to the RF OUTPUT connector Use a small straight slot type screwdriver to adjust the potentiometer if adjustment is necessary Counterclockwise rotation of the potentiometer decreases the RF output level If an output level of less than 40 dBmV is required add an attenuator of the appropriate value to the modulator output Example For an output level of 35 dB...

Page 11: ...ront Panel Controls and Indicators Items 3 4 sections of this manual for details To monitor the audio source material plug a set of headphones into the MONITOR OUTPUT jack Adjust the MONITOR Level control for a comfortable listening level 3 Connect the Transmitter to Power Plug the DC power cord of the supplied AC Adapter into the DC INPUT connector on the rear panel of the FMC 1000 unit Secure th...

Page 12: ... is repaired in five to ten working days after it arrives at R L DRAKE if we have all the facts If we must call you it may take longer R L DRAKE is not responsible for damage caused by lightning nonprofes sional alterations acts of God shipping damage poor storage handling etc R L DRAKE will make note of any shipping damage upon receipt Should your warranty card not be on file at R L DRAKE you wil...

Page 13: ...are important to obtain proper performance from this product Therefore carefully read the Instruction Manual This warranty does not apply to any defect that R L DRAKE COMPANY determines is due to 1 Impropermaintenanceorrepair includingtheinstallationofpartsoraccessoriesthatdonotconformtothequality and specifications of the original parts 2 Misuse abuse neglect or improper installation 3 Accidental...

Page 14: ...R L DRAKE COMPANY 230 INDUSTRIAL DRIVE FRANKLIN OHIO 45005 U S A CUSTOMER SERVICE AND PARTS TELEPHONE 1 937 746 6990 TELEFAX 1 937 743 4576 WORLD WIDE WEB SITE http www rldrake com ...

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