MEGACODE MDT-4A Digital Transmitters Instruction Manual
- June 13, 2024
- MEGACODE
Table of Contents
MEGACODE MDT-4A Digital Transmitters
DESCRIPTION
The MegaCode series of digital transmitters are wireless radio controls
designed for use with automatic garage door and gate 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 the 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).
Installation Instructions
STEP 1 Receiver Installation. Connect the receiver to the garage door
operator as described in the receiver’s Installation Instructions. Apply power
to the operator before programming.
CONNECT RECEIVER TO GARAGE DOOR OPERATOR
STEP 2A MDR/MDRNR/MDR2 Program button and LED Location. Locate the
program button and LED on the side of the receiver case.
STEP 2B MDRM/MDRM2 Program button and LED Location. Locate the program
button and LED on the back of the receiver
case.
STEP 3 Program receiver. Momentarily press the receiver’s program button
(channel one or two). The red programming LED 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
2seconds.
↳ 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 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.
STEP 5 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 the button. Count the number of flashes. The number of flashes equals
the number of transmitters programmed into that channel of the receiver.
↳ NOTE: Don’t hold down the programming button longer than 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 operator should activate. Wait 2 seconds between each activation.
STEP 7 Erasing receiver memory. Transmitters may be erased from the
receiver’s memory 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 erased. All
transmitters for each receiver channel are erased at the same time.
INFO 1A Opening battery compartment. To access the transmitter’s
batteries remove the battery access screw on the back of the unit. Flip the
unit over so that the front is facing you. Use a small screwdriver to open the
battery compartment.
INFO 18 Replacing transmitter batteries. Replace the two batteries with
two Type 2032 lithium batteries or equivalent. The batteries stack on top of
each other with the (+) sides facing the front of the transmitter. Replace
with new batteries then close the battery compartment, replace battery access
screw and test transmitter.
INFO 2 Visor Clip Removal. The visor clip can be removed by removing the
three screws as shown. Slide the clip off the retaining plate and reattach the
plate to the transmitter.
↳ 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.
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 vary 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.
800-421-1587 •
www.linearcorp.com
