Model Train Technology G-Controller User manual

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G-Controller™
OPERATIONS MANUAL
Version 1.1a

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INTRODUCTION
Video Instructions: https://youtu.be/FRAdZwGpwZQ
The Model Train Technology™ G-Controller™ provides an
extremely simple plug-and-play system for lighting and
animating G Scale block signals and RR Crossing Flashers.
• No Soldering
• No Computer
• No Programming
Our simplified system will provide great animation in just a
few minutes of installation time, not days or years and at a
fraction of the cost of elaborate CTC systems and no
programming is involved.
Summary of Precision Detector MAX Features:
• Long, precise sensor range (10 to 600 mm)
• No more adjusting for varying light conditions.
• Auto-calibration mode for precise range setting
• Detect one parallel track and ignore the others
• Adjustable time-out (0-30 seconds)
• Electrical box integrated design
• Includes a 2mm screwdriver.

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OVERVIEW
Each MTT G-Controller (“Controller”) stands on its own and is
triggered by a Precision Detector MAX™ sensor, mounted
either on the front or back of the main circuit board
depending on whether you have the battery or wired 12VDC
version. Our Precision Detector™ technology was
incorporated in the Controller design using a cousin of the
earlier chip for range detection. The chip for the G-Controller
has a longer range but otherwise has the same characteristics
as our standard detector. This is not an IR sensor, so it is not
affected by the typical and difficult lighting conditions of
indoor or outdoor layouts, including when facing into the sun.
You can connect additional Precision Detectors to the
Controller to extend detection areas or catch East/West traffic
for crossing signals.
When the Controller is tripped by the sensor, it starts a display
(aspect) cycle that begins with red. While the sensor shows
occupied, the Controller will stay red. Once the block
(detector) is cleared, the Controller will start a change of light
sequence based on one of the options shown below. The time
between stages can be adjusted on the Controller.

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The Controller has four outputs that are synchronized to the
selected aspect behavior. You can adjust the brightness of
each of the outputs individually. This lets you set the
brightness appropriate to your layout. You can also
individually adjust each of the different colored LEDS. The
typical colors of the LEDS (Red, Yellow and Green) do not glow
at the same brightness with the same voltage. The Controller
allows you to adjust them to your liking. No resistors are
needed! The Controller supports both common anode and
cathode (UNIVERSAL version only).
The Controller allows you to set the speed by which the
Aspect (colors) shifts from Red to Yellow to Green after the
train has passed and the block is unoccupied. You can make it
occur almost immediately, or you can set it up to 30 seconds.
Each Controller has its own speed adjustment
The Controller has eight distinct behaviors that are set with
the single push button. The time between stages is set with
the screwdriver(provided) and trim screw. They are:
• Red, Green
• Red, Yellow, Green
• Red, Yellow, Yellow flash, Green

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• R, R&Y, G&Y, Green
• R, R&Y, R&Y-Flash, G&Y-flash, Green
• Red, fade to Yellow, fade to Green
• Alternate flash Red & Green (speed adjustable) *
• Alternate flash R & G with fade (speed adjustable) *
*For use with gate crossings.
There are two types of controllers:
1. Battery Powered
2. 12VDC Powered
Functionally, they are identical.
The Controller for LEDs operates at 7.4v (Battery) or 12VDC.
The LEDs are powered up to 5VDC but there are built in
resistors to limit the current to “safe” levels for the LEDs we
use in our signals. The Controller can light two LED block
signals each with three 2-5v LEDS or up to four Crossing
Flashers.
The circuit board has been coated with a Conformance coating
to reduce oxidation on electrical components.

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LATCHING (Clear-to-Proceed)
While not a true CTC signaling system, there is one feature
that will give the appearance of one – without the complexity.
In short, if you connect the Signal wire of the G-Controller
from the block ahead to the LATCH terminal of the G-
Controller of the block behind, while the block ahead is
occupied the block behind will wait at the last aspect before
green. Once the block ahead is clear, the G-Controller of the
block behind is “released” and will turn green. You can daisy-
chain as many latching connections as you like.
Here Is the wiring for Latching:

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G-Controller Circuit Board
P2 -Sensor Timeout &
Brightness adjustment
P1 - Aspect Changing
Speed adjustment
P3 -Detect Range
adjustment
Select Button
Battery ON/Off
Signal Out
Ground/Common
Latch IN terminal
Detect IN terminal
RED
YELLOW
GREEN
CENTER
COMMON/GND
BATTERY OUT for
Battery Version and
12VDC In for NON-
Battery version
Shed Light
Connector
Blue
Indicator
LED
The circuit board components are exposed when you handle the board outside of the case.
Be as careful as you can not to touch the components themselves and avoid static electricity.
DO NOT CONNECT 12VDC to the BATTERY VERSION of the G Controller. IT WILL FRY THE BOARD
SENSOR
LED output
voltage Jumper

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SETUP AND OPERATION
If battery powered, slide the battery power switch into the
UP/ON position. Otherwise, activate your 12VDC supply.
After 1 second the blue indicator LED will flash four times
rapidly and the green LED will light.
If you put your hand or an object in front of the sensor, the
blue LED will light, and the Controller will change the aspect to
RED (Occupied).
The default range on the sensor is set to a max range of 600
mm or about 20 inches. The Zone mode is STANDARD, which
means anything in the range of the sensor will be detected.
The Aspect SPEED is set low (fast speed) so that you can
quickly see the aspect change when you move away from the
detection zone of the sensor.
To Slow down the rate of aspect change, turn the P1 trim
potentiometer (trimPot) to the right (increasing time) using
the small screwdriver provided.
The sensor timeout is also set to low (immediate) so that
when you move away from the sensor it times out
immediately. That is shown by the blue LED turning off.
Adjusting the P2 Sensor Time Out allows you to delay when

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the Controller is released after the train passes. For example,
the train could pass, and the controller might wait 20 seconds
(stay RED) until it starts the aspect timer. This helps to
increase realism of the signal changes.
Another reason to use the time out adjustment is to AVOID
the sensor going off when it sees a gap between train cars.
The sensor is very precise and fast. This effect is less
pronounced if the sensor is near its max range from the track
but may occur if the sensor is close to the track. Increasing the
timeout to 1-2 seconds helps to avoid this situation.
SELECTING A SIGNAL BEHAVIOR (ASPECTS)
You push the Select Pushbutton the number times needed to
select an option according to the table below. Once you stop
pushing the button the Controller will wait 2 seconds and then
all the LEDs will turn off. One second later the green signal
LED will blink the number count matching the button pushes.
PUSHES
SIGNAL BEHAVIOR
2
Red, Green
3
Red, Yellow, Green
4
Red, Yellow, Yellow flash, Green
5
R, R&Y, G&Y, Green
6
R, R&Y, R&Y-Flash, G&Y-flash, Green
7
Red, fade to Yellow, fade to Green

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8
Alternate R & G no fade (speed adjustable)*
9
Alternate R & G with fade (speed adjustable) *
* For use with Gate Crossing Flasher
The default setting is 3.
SELECTING THE ASPECT SPEED – P1
The behavior speed adjustment screw is inside the Controller.
You access it with the provided 2mm screwdriver. Gently turn
the screw inside from zero to about 300 degrees. It does not
turn 360 degrees. Left or counterclockwise is faster (less time
between stages), right or clockwise increases the time
between stages. You can make the adjustment at any time
since the Controller reads the setting at the beginning of each
detector trip event.
FORWARD LATCHING
The way standard latching works is the G-Controller in the
forward block “holds” the G-Controller behind it at the YELLOW
stage until the train is clear of the forward block. Once clear
the train is clear of the forward block, it releases the latch and
the block behind it is cleared to Green.

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This all assumes that the trains are on the same track heading
in the same direction. This also means that the blocks have
been tripped by detection.
Forward Latching allows a G-Controller (via Detection) to cause
a “Non-tripped” G-Controller to instantly show Yellow.
This would normally be caused by two trains approaching each
other with a passing siding nearby. Forward latching tells the
“second” train to slow down (via the yellow indication). It
could also be set to red by connecting another detector that is
in the closer block.
You DO NOT have to configure Reverse Latching. It happens
automatically if the latching wire is connected, and the
conditions explained happen.
Here is an example:

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RESET
To reset the Controller to factory defaults, press the SELECT
button 13 times.
SETTING THE RANGE TO STANDARD MODE
By default, the sensor is set to detect the range from 10mm to
600mm. If you happen to have set the range to ZONE mode,
press the SELECT button 11 times to return to STANDARD
MODE. We recommend you start with the STANDARD mode
for testing purposes.
To shorten the detect range, turn the P3 trim pot to the left
(counterclockwise). Test this by moving your hand, or some
object, from outside the range to closer until the blue light
goes on. In this mode, anything from 10mm away from the
sensor
Next, using the provided screwdriver, turn the right-hand trim
pot to the right about ¼ turn (or 15 minutes’ worth if you
want to use a clock metaphor). Then wave your hand in front
of the sensor and then away. The LED should stay lit for a
second and then go out.

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SETTING THE RANGE TO ZONE MODE
To avoid objects, people, cats, lizards (?) from accidentally
tripping the sensor there is ZONE mode. ZONE mode is a
70mm wide detection zone that can be positioned anywhere
within the max range of 600mm. To set the detector into
ZONE mode press the SELECT button 12 times.
Now, adjust the LOCATION of the START of the ZONE by
adjusting the P3 detector range trim pot.
Start with the trim pot turned all the way counterclockwise.
Then put a car on the track where you want the zone. Turn
the trim pot back to the right (clockwise) until the blue light
goes on. That’s it. The zone is now set to minimize any object
outside the width of the track.
To test this, start outside the max range and move your hand
inward until the blue light comes on indicating the outside of
the zone. Keep moving your hand inward. After about 70mm
of movement inward the blue light will go out – and stay out
all the way to the start of the sensor range of 10mm. You will
want to locate this zone so that a railcar on the tracks trips the
sensor but anything reasonably outside the zone does not.

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AUTOMATIC RANGE CALIBRATION
The Precision Detector includes a feature called Auto
Calibrate. This make setting the exact distance for detection
to a rail car extremely simple.
STEPS:
1. To activate the saved calibration, the trim pot for ranging
must be set to zero. Turn the trim pot with the
screwdriver all the way to the left (counterclockwise).
2. If this is the first time to use calibration, the saved setting
may also be zero.
3. Press and hold the select button on the sensor. If your
finger sets off the sensor (blue light), don’t worry. While
you continue to hold the select button the blue light will
go off. Hold the button for about 8 seconds and then the
blue light will come back on. When the light comes back
on, release the button.
4. The blue LED will blink at 1 per second. The Controller is
now in CONFIGURATION MODE. To start the Auto
Ranging cycle, press the select button again twice (after
to you see it blinking)

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5. The LED will THEN blink 10 more times, once per second,
to allow you time to place a train car on the track in front
of the sensor you wish to calibrate.
6. After 10 seconds (10 blinks) there will be a 1 second
pause and then the LED will blink very rapidly for about 1
second. This rapid blinking is when the sensor Auto
Calibrates (measures) the detected train car distance.
That distance is saved in the memory of the sensor.
7. After the rapid flashing the sensor LED will go out for 2
seconds and then return to normal operating mode. The
LED should go back on since it now detects the rail car on
the track in front of it. Move the rail car and the LED
should go out.
NOTE: It is BEST to set the P2 timeout adjustment to zero
so that the LED will go out immediately after you move
the rail car. This makes confirming the correct operations
much easier.
8. Anytime that you want to use your own setting, simply
adjust the trim pot accordingly using the provided
screwdriver. When the trim pot is zero, the Auto

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Calibrate value is used and the trim pot is ignored. When
the trim pot is non-zero, the setting of the trim pot is
used.
TRIGGER TIMEOUT SETTINGS
Rotate the P1 trim pot clockwise to increase the length of the
detector timeout up to 30 seconds.
CONFIGURATION MODE OPTIONS
For the following setting you will need to enter the
Controller’s configuration mode.
1. Press and hold the select button on the sensor. If your
finger sets off the sensor (blue light), don’t worry. While
you continue to hold the select button the blue light will
go off. Hold the button for about 8 seconds and then the
blue light will come back on.
2. When the light comes back on, release the button. The
blue LED will blink at 1 per second.

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3. The Controller is now in CONFIGURATION MODE.
SETTING THE LED BIGHTNESS
Setting the brightness for each output is accomplished
through a series of pushes to the select button.
In CONFIGURATION MODE, press the select button the
number of times according to this chart for the LED you wish
to adjust:
RED 3
YELLOW 4
GREEN 5
CENTER 6 ( for 7 light signals)
The LED that you selected will light and the BLUE LED may
flicker.

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Gently Insert the screwdriver into the P2 adjustment screw
hole and turn the insider screw clockwise and counter
clockwise to reach the desired brightness for the red LED.
When you turn the P2 trimPot, the blue LED will flicker. This
lets you know that something is happening.
When you are happy with the setting, press the select button
once. This will save the Red LED setting; the Red LED will blink
and go out. The Controller will exit CONFIGURATION mode
any time you press the SELECT button once.
To avoid having re-enter CONFIGURATION MODE, such as
when you want to adjust all the LED brightness in sequence,
instead of pressing SELECT once, simply press the number of
times for the next color to adjust. So, for yellow, pressing 4
times will SAVE the Red setting and then light the Yellow light
ready for adjustment. Likewise, if you were then to press the
button 5 times. Press once to save after the last adjustment.
After you have exited CONFIGURATION MODE the Controller
will go back to normal operations – which will be a Green
signal unless the sensor was tripped.
If you have selected either behavior 8 or 9, which are the
crossing gate alternate flash modes, all the LEDs will remain
off until a block occupied trip signal is received.