Operating Instructions; Selecting The Compatibility Mode; Adjusting Transmitter Frequency - Lectrosonics MM400C Instruction Manual

Operating Instructions

Selecting the Compatibility Mode

All Digital Hybrid receivers are capable of working with
Lectrosonics MM400C transmitter, and by setting the
proper Compatibility Mode, the unit will also work with
200 Series and 100 Series analog receivers, plus some
other brands (contact the factory for details). In order
to operate properly, the transmitter must be set to the
operating mode of the matching receiver, which is easily
done using a small screwdriver and a battery.
The following procedure assumes that the Power
ON/OFF switch is configured for Normal Mode. If it
has been configured for Audio Mute Mode, see Power
Switch Function Selection to change the configuration
to Normal Mode.
Note: The unit comes from the factory in the Digital
Hybrid mode.
1) Set the audio controls for the corresponding re-
ceiver to minimum.
2) Install a good battery in the transmitter. Move the
Power Switch to ON and observe the Modulation
LEDs to determine the current Compatibility Mode.
The –20 and –10 LEDs will blink simultaneously:
• Once for 100 Series mode
• Two times for 200 Series mode
• Three times for "Other" receivers
• Four times for 400 Series mode
• Five times for IFB Series mode
3) Move the Power Switch to the OFF position.
4) Loosen the Frequency Switch Cover Plate
Retaining Screen and rotate the cover to
expose the Frequency Select Switches.
With a small screwdriver (included
with your unit), set the Frequency
Select Switches to CC. (for
Change, Change).
5) Power up the unit briefly – just
long enough to watch the
LED's glow and then turn
Modulation LEDs
POWER LED
Rio Rancho, NM
Watertight Miniature UHF Belt-Pack Transmitter
6) Change the Frequency Select Switch settings to
7) Power up the unit briefly – just long enough to
8) Set the Frequency Select Switches to 0,0.
9) Turn on the transmitter and observe the Modulation

Adjusting Transmitter Frequency

If you are experiencing interference from another signal
on your operating frequency, you may need to change
the operating frequency of your system. This is done
through two Frequency Select Switches located under
the Frequency Switch Cover Plate on the bottom of the
transmitter case.
The left switch is for coarse frequency adjustment, and
it increments the operating frequency in 1.6 MHz steps.
The right switch is for fine frequency adjustment and it
increments the operating frequency in 100 kHz steps.
If you are using a 200 Series or 400 Series receiver,
it is suggested to use the built in frequency spectrum
scanning function on the associated receiver to find a
clear channel. Turn the transmitter off and leave the
receiver turned on. Scan across the frequency band to
find a frequency where little or no RF activity is dis-
played. Set both the transmitter and the receiver to this
new frequency. Turn on the transmitter to ensure the
RF signal is strongly indicated at the receiver.
Power ON/OFF
Switch
the transmitter Off.
one of the following positions:
• 100 Series mode:
• 200 Series mode:
• Mode 3:
• 400 Series mode:
• IFB Series mode:
watch the LED's glow and then turn the transmitter
Off.
LEDs to verify the compatibility mode for the unit
has changed.
NOTE: Each time the transmitter is turned on, the
Modulation LEDs will confirm the current operating
mode with the number of blinks listed in Step 2.
The mode setting will not change until reset with
the procedure listed above.
1.6M
0 1
F
E 2
D 3
C 4
B 5
A 6
9
7
8
Frequency Select Switches
1,1
2,2
3,3
4,4
5,5
100K
0 1
F
E 2
D 3
C 4
B 5
A 6
9
7
8
11