V2 T238 Digital Trigger Unit V2.0
(With overheat protection & auto-loading)
This upgrade kit is designed for professional AIRSOFT/gel ball blaster
player who can fully disassemble and assemble Automatic Electric Gun. The
compatibility with all Gearboxes is not guaranteed, but it can fit into standard or
common brand Gearboxes V2 without larger modification. Related Tools and
skills is needed for installing the product.
- Shim the gearbox before installation.
- Protect the detection sensors while installing, keep the sensors clean, make sure that nothing is blocking the sensors.
- Mind the positive and negative of the motor, do not reverse.
- The DTU will not work correctly before the motor is installed with the
- Operating voltage: 7.4-11.1V
- Integrated Bluetooth wireless communication module
- Programming via Bluetooth using smart phones
- Free APP for Android
- Active break tech & Piston reset
- Programmable auto-loading function
- Multiple programmable shooting mode
- Overheat protection
- Maximum Inrush current is 240A, Maximum Brake current is 100A
- Compatible with various Standard Gearbox V2
- Pre-cocking control
- Rate of fire control
- Active braking effect control
- Sensors monitor
- DTU current, voltage and temperature report
- Total shot count and power-on time count
- Low battery voltage protection, the default setting is protection OFF. Change the battery when hearing ‘4~3~2~1’ 4 beeps low voltage
- Block-up protection. When gearbox Block-up occurs, the system stops
working and emits an elongated ‘1~’ beep. Please check the gearbox
immediately by power off.
- Auto-loading function is designed for gel ball blaster magazines with
motor inside, when changing the magazine, the magazine motor will
run automatically for a period of time, and the length of time can be
programmed by 9th option.
- This module is able to increase rate of fire, the stability of single-shot
and make batteries have higher durability.
- The energy that support the active brake function comes from the
inertia of motor, stop the piston without delay. The effect of active
brake is significant on high torque motor
- The active function prevents the over-spin of gears, this solve the
issue that the single shot becomes multiple shot under high voltage. Meanwhile, the spring is fully released in semi-auto mode and parts in
gearbox are not under strain, increase the life cycle of gearbox and
- The system includes multiple shooting mode, these modes can be
selected by fire select switch
- The default position of the piston is adjustable in semi-auto mode. Pre-cocking function can be implementing, zero trigger delay
- Adjustable rate of fire, the gap between two single shots can be
programmable, to achieve adjustable rate of fire
- When the DTU is overheated, after the trigger is pulled, the motor will
give a beep prompt until it is automatically restarted after cooling.
- SAFE：This mode is completely the same as original safe mode. The trigger
can be pull but nothing happens. This mode can be programmed to semi-auto, double stroke single shot, 3-round burst to 6-round burst,
the default mode is safe mode
- SEMI: This mode can be programmed to semi-auto, double stroke single shot, 3-round burst to 6-round burst, the default mode is semi auto
- AUTO: This mode can be programmed to full-auto, 3-round burst, 6-round
burst and 9-round burst, the default mode is Full-auto
- Receiving sensors: 5 trigger receiving sensors, 1 gear receiving sensor, 1
semi-auto sensor and 1 full-auto sensor.
- Transmitting sensors: 1 trigger transmitting sensor, 1 gear transmitting
sensor and 1 selector transmitting sensor.
How does it works: The transmitting sensors emit light of a specific frequency, and the receiving sensors change the output signal when it receives it. The
DTU reacts according to the signal of the receiving sensors. Sunlight and
some lights contain light of that specific frequency, be careful to avoid
interference and keep the sensors clean.
- Gear sensors: When installed correctly, the gear transmitting sensor and
the gear receiving sensor are located on both sides of the sector gear. When
the sector gear rotates to a specific position, the gear receiving sensor will be
blocked, so that the gear receiving sensor can not receive the signal from the gear transmitting sensor. The DTU detects the angle of the sector gear
according to the output signal of the gear receiving sensor.
- Trigger sensor: When installed correctly, the trigger transmitting sensor
and the trigger receiving sensors are located on both sides of the trigger. When
the trigger is fully released, the trigger receiving sensors will be blocked, so
that the trigger receiving sensors can not receive the optical signal from the
trigger transmitting sensor. When the trigger is pressed, the trigger will no
longer block the trigger receiving sensors, and the trigger receiving sensors
can normally receive the signal from the trigger transmitting sensor. The DTU
detects the angle of the trigger according to the output signal of the trigger
- Selector sensors: Selector sensors need white sticker on selector plate to
work correctly, When installed correctly, the optical signal emitted by the
selector transmitting sensor is reflected by the white sticker and received by
the semi-auto and full auto sensors. The distance between the white sticker
surface and the sensors cannot be greater than 2mm and less than 0.5mm
- When the selector plate in the SAFE position, the white sticker reflect
nothing, the semi-auto sensor and full-auto sensor can not receive the
- When the selector plate in the SEMI-AUTO position, the optical signal from
the transmitting sensor is reflected by the white sticker and received by the
semi-auto sensor, but the full-auto sensor can not receive the optical
- When the selector plate in the FULL-AUTO position, the optical signal fromthe transmitting sensor is reflected by the white sticker and received by
both the semi-auto sensor and the full-auto sensor.The DTU detects the position
of the selector according to the output signal of the semi-auto and full-auto sensors.
- High-power soldering iron (higher than 50W) is recommended, solder the
clop with 0.5sqm soldering wire and soldering rosin. Please ask
professional for help if you do not know to solder.
- Please use Spring smaller than M150.
- Use high torque motor(no load current less than 3A) can stop the motor
faster and prevent DTU from overheating.
- In standby state, the current of the system is smaller than 0.05A. Please
disconnect the battery if it is not used for a long time.
Installation click HERE
APP for Android:
Download and install the. APK file from the website: http://github.com/t238. After installation, enter the settings -> APP¬ification, find the “T238DTU”, go to APP permissions -> location permission, and select “Allow all the time”. This will allow the smart phone APP to fine the Bluetooth devices.
Bluetooth programming function will be turned off in 30 seconds after power on. Connecting DTU with smart phone needs to be completed within 30 seconds
after power on, otherwise, the DTU needs to be powered off and powered on
again. Open the app, click “Search” button to find the Bluetooth device “T238DTU” and connect it.
There are five trigger sensors, which are convenient to adapt to different
trigger rotation angles. When using DTU for the first time, trigger calibration is
required. The specific operation is as follows: install the gearbox, grip and
motor, connect the battery, when the prompt tone “1~2~3~3~2~1~” is heard, hold the trigger, and then release it. After repeating three times, the prompt
tone “1~2~3~” will be heard, indicating that the DTU has been calibrated. The
trigger rotation angle of different gearboxes is different, so it needs to be
recalibrated when replacing gearbox or trigger. To recalibrate the trigger, connect the app and restore the DTU to the factory settings. Restore factory
settings is in the “Module parameter set”.
Open the app, click “Search” button to find the Bluetooth device “T238DTU” and connect it.
Go to “DTU Sensors Monitor”, and enable the “Enable monitoring” checkbox, move the trigger, selector plate and the sector gear to see if the corresponding
checkbox changes. If no, means that the corresponding position sensor is
faulty or the installation is faulty, and the corresponding sensor cannot be
triggered. It is suggested to open the gearbox for investigation.
1. Basic setting
Reset: reset the basic settings to the default settings.
Load: load basic settings from DTU.
2. Advanced setting
Reset: reset the advanced settings to the default settings.
Load: load advanced settings from DTU.
3. Gearbox stats
Shot Counter: count the number of shots of gearbox.
Power-up Time: count the power on time of gearbox.
Average Rate of Fire: calculate the average rate of fire in fully automatic firing
4. Sensor Monitor
Optical Sensors Input: trigger sensors0~4, gear sensor, semi-auto sensor,
Electrical Sensors: voltage sensor, current sensor, temperature sensor.
Magazine port: this port is designed to detect the connection of gel ball
Extended ports: not yet developed
5. Operation Report
Refresh: refresh the report data.
Input Voltage: current input voltage.
Max Input Voltage: historical maximum input voltage.
Min Input Voltage: historical minimum input voltage.
Motor Start Current: average starting peak current of motor during the last
Average Semi-auto Current: average motor current during the last
Average Full-auto Current: average motor current during the last Full-auto
MOSFET Temperature: current temperature of MOSFET.
Max MOSFET Temperature: historical maximum temperature of MOSFET.
Min MOSFET Temperature: historical minimum temperature of MOSFET.
6. Battery Charge Report
Type: the supported battery types are Li-Fe and Li-Po.
Voltage: the supported voltage range is 2.5~12.6V.
Power: percentage of remaining electricity
Acquisition power: refresh the displayed data
7. Device Information
8. Module Parameter Set
9. GPS Locate