MegaCode Series
MDT, MDT-2, MDT-4
DIGITAL TRANSMITTERS
Installation Instructions
(800) 421-1587 • www.linearcorp.com
MDT
DESCRIPTION
The MegaCode series of digital transmitters are wireless radio controls
designed for use with automatic garage door and g ate openers. The
MegaCode radio format provides unparalleled security. The system
can be programmed to more than a million different codes.
MegaCode transmitters and receivers do not contain a typical “coding
switch” as in Linear’s standard digital receivers. Each transmitter is
pre-set at the factory to a unique code. The receiver is programmed by
sending a signal to it from the transmitter(s) that are going to be used
with it. This stores the transmitter’s code into the receiver’s memory.
The receiver will retain its memory even without power. The receiver
will activate only from these “memorized” transmitters. Please refer to
the receiver’s instructions for maximum transmitter capability.
The transmitters are powered from two Type 2032 lithium “button cell”
batteries. When the batteries get low, the bright red LED light on the
transmitter will start to dim as the unit is activated. When the red LED
no longer lights when the transmitter is activated, the batteries should
be replaced.
MDT - Single-channel transmitter with a button on the front and th e
top (both buttons perform the same function).
MDT-2 - Three-channel transmitter with two buttons on the front and
one button on the top (each button performs a separate function).
MDT-4 - Five-channel transmitter with four buttons on the front and
one button on the top (each button performs a separate function).
MDT MDT-2 MDT-4
STEP 1
Receiver Installation. Connect the receiver to the
garage door operator as describe d in the receiver’s Installation
Instructions. Apply power to the op erator be fore program ming.
CONNECT RECEIVER TO GARAGE DOOR OPERATOR
STEP 3
Program receiver. Momentarily press the receive r’s
program button (channel one or two). The red program mi n g LE D
will light if there’s room in the receiver’s memory for another
transmitter. The LED stays on for about 5 seconds. A transmitter
must be entered
while the LED is on
. Press the desired
transmitter button. The LED will flicker indicating that the receiver
has accepted the transmitter.
NOTE: Be sure to press the receiver program button for less than
➥
2 seconds.
WARNING! Door operator will not activate when the receiver
➥
is being programmed from the transmitter, but the door
operator will activate the next time the transmitter is activated
after programming.
➥
NOTE: The programming LED also monitors radio signals entering
the receiver. It is common to see an occasional blink from the LED.
The LED will also light when any transmitter tuned to the receiver’s
frequency (programmed into the receiver or not) is activated.
STEP 2A
MDR/MDRNR/MDR2 Program button and LED
Location. Locate the program button and LED on the side of the
receiver case.
CHANNEL ONE
PROGRAMMING
BUTTON
PROGRAMMING
LED
CHANNEL TWO
PROGRAMMING
BUTTON
WHEN RECEIVER
IS READY, PRESS THE DESIRED
TRANSMITTER BUTTON
1
H
C
2
H
C
CHANNEL 1
PROGRAMMING
BUTTON
CHANNEL 2
PROGRAMMING
BUTTON
LED WILL LIGHT
WHEN RECEIVER
IS READY
RECEIVER LED
WILL FLICKER
AS TRANSMITTER
IS ENTERED INTO
MEMORY
STEP 2B
MDRM/MDRM2 Program button and LED
Location. Locate the program button and LE D on the ba ck of th e
receiver case.
CHANNEL ONE
PROGRAMMING
BUTTON
CHANNEL TW O
PROGRAMMING
BUTTON
PROGRAM MING
LE D
STEP 4
Add additional transmitters. Repeat Step 3 for each
transmitter used with the receiver. Be sure to press the receiver’s
program button
each time
a new transmitter or a different
transmitter button on a multi-button transmitter is pressed.
If the LED doesn’t come on when the receiver’s program button is
pressed, the receiver’s memory is full. Use the erase function (Step 7)
to remove transmitters form the receiver’s memory.
1
H
C
2
H
C
PRESS CHANNEL 1 OR CHANNEL 2
PROGRAM BUTTON FIRST
THEN PRESS TRANSMITTER BUTTON
WITH MULTI-BUTTON
TRANSMITTERS PRESS
THE DESIRED BUTTON
STEP 5
REMOVE VISOR CLIP
BY REMOVING THREE
SCREWS
Review memory. Press and hold the receiver’s
program button (channel one or two) until the LED begins to flash
(about 3 seconds) and then release t he button. C ount the nu mber
of flashes. The number of flashes equals the number of
transmitters programmed into that channel of the rece iver.
NOTE: Don’t hold down the programming button longer t han
➥
5 seconds, the receiver’s memory for that channel will be
erased (Step 7).
STEP 6
Test receiver.
Be sure door area is clear.
Activate
each transmitter. The receiver relay should click (relay output
models only) and the operato r should activate. Wait 2 seconds
between each activation.
STEP 7
Erasing receiver memory. Transmitters may be
erased from the receiver’s memo ry by pressing and holding the
receiver’s program button (channel one or two) for 5 seconds or
more. After the LED blinks (count of transmitters) it will blink one
more time for channel one and twice for channel 2 as the
receiver’s memory for that channel is erase d. All transmitters
for each receiver channel are erased a t the same time.
CH1
INFO 1A
CH2
PRESS PROGRAM BUTTON
(CHANNEL 1 OR 2)
FOR THREE SECONDS
THEN RELEASE
LED WILL FLASH, COUNTING THE
TOTAL NUMBER OF TRANSMITTERS
PROGRAMED TO THAT CHANNEL
Opening battery compartment. To access the
CH1
CH2
transmitter’s batteries remove the b attery access screw on the
back of the unit. Flip the unit ove r so that the front is facing you.
Use a small screwdriver to open the ba ttery compa rtment.
REMOVE BATTERY
ACCESS SCREW
FLIP
TRANSMITTER
OVER
32
20
SWING BATTERY
COMPARTMENT OPEN
WARNING!
INFO 1B
BE SURE DOOR
AREA IS CLEAR
OF OBSTRUCTIONS
Replacing transmitter batteries. Replace the two
PRESS TRANSMITTER
BUTTON TO TEST
batteries with two Type 2032 lithium bat te ries or equiva lent. The
batteries stack on top of each othe r with the (+) sides fa cing the
front of the transmitter. Replace with new batteries then close the
battery compartment, replace battery access screw and test
transmitter.
REPLACE
WITH TWO
TYPE 2032
BATTERIES
SIDE UP
CH1
CH2
PRESS PROGRAM BUTTON
(CHANNEL 1 OR 2)
FOR FIVE SECONDS OR MORE
INFO 2
Visor Clip Removal. The visor clip can be rem oved
CH1
CH2
LED WILL FLASH, COUNTING THE
TOTAL NUMBER OF TRANSMITTERS
PROGRAMED TO THAT CHANNEL.
THEN IT WILL BLINK ONE MORE TIME
AS THE TRANSMITTERS ARE ERASED
FROM THAT CHANNEL
by removing the three scre ws as shown. Slide the clip off the
retaining plate and reattach th e plate t o the t ransmitter.
NOTE: The same transmitter (or the same transmitter button on
➥
multi-button transmitters) cannot be programmed into both
receiver channels 1 and 2.
➥
NOTE: If the receiver’s LED flashes continuously when a
transmitter isn’t being activated, the receiver is too close to an
electrical noise source. Move the receiver away from the noise
source or call technical services for assistance.
CH1
CH2
CONTINUOUSLY FLASHING LED MAY
INDICATE ELECTRICAL NOISE
INTERFERRENCE
LIMITED WARRANTY
This product is warranted to the consumer against defects in material and
workmanship for one year from the date of purchase. This warranty applies
to first retail buyers of new devices. Warrantor will repair, or at its option,
replace, any device it finds that requires service under this warranty, and
will return the repaired or replaced device to the consumer at the
warrantor’s cost. For warranty service and shipping instructions contact
warrantor at the address shown below. Devices must be sent to warrantor
for service at owner’s expense. The remedies provided by this warranty
are exclusive. Implied warranties under state law are to the one year period
of this written warranty. Some states do not allow limitations on how long
an implied warranty lasts, so the above limitation may not apply to you. In
order to be protected by this warranty, save your proof of purchase and
send copy with equipment should repair be required. This warranty gives
you specific legal rights, and you may also have other rights which v ary
from state to state.
All products returned for warranty service require a Return Product
Authorization Number (RPA#). Contact Linear Technical Services at
1-800-421-1587 for an RPA# and other important details.
IMPORTANT !!!
Linear radio controls provide a reliable communications link and fill an
important need in portable wireless signaling. However, there are some
limitations which must be observed.
For U.S. installations only: The radios are required to comply with FCC
✶
Rules and Regulations as Part 15 devices. As such, they have limited
transmitter power and therefore limited range.
A receiver cannot respond to more than one transmitted signal at a time
✶
and may be blocked by radio signals that occur on or near their operating
frequencies, regardless of code settings.
Changes or modifications to the device may void FCC compliance.
✶
Infrequently used radio links should be tested regularly to protect against
✶
undetected interference or fault.
A general knowledge of radio and its vagaries should be gained prior to
✶
acting as a wholesale distributor or dealer, and these facts should be
communicated to the ultimate users.
Copyright © 1999 Linear Corporation 207779 D