Note: A radio amateur license is required.

The “2M Arduino 818” series is designed as an APRS tracking device. With the “Trackuino 818 Plus” software, the system can send position, weather, and telemetry packets. For information on the “Trackuino 818 Plus” refer to the description on https://github.com/kghill/2M-Arduino-818.

The board includes a:

• GPS NEO-6M GPS module
• SA818 VHF Transceiver module for ½ w or 1 w applications
• 7-element low pass filter for 2 meters
• SMA Female 50-ohm connector, optional straight antenna, or 90-degree antenna connector provided.
• DS18b20 sensor to measure internal or external temperatures
• Vin voltage sensor

Optional BME290: An optional BME280 sensor can be installed to measure temperature, humidity, barometric pressure. Software drivers for the BME280 are part of the “Trackuino 818 Plus” software.

Instead, the I2C interface can be used for other I2C compatible devices.

The board comes in two voltage models and is shown as two separate products:

• "2m Arduino 818-12v" for 7-to-12-voltage source and used with the Uno processor board
• "2M Arduino 818-3.7v" for 3.7-volt solar 1s lithium battery source and used with the "Solar Pro Mini 1s" processor board (coming soon)

The intent of the 2M Arduino 818-12v model is to use it in a vehicle, boat, plane, etc. where a 12-volt battery is available and APRS position reporting is desired. The voltage source to the boards is thru the DC jack. The onboard voltage regulator is used to power the 818 and other components via the Vin Pin. Note: Proper ventilation is required to prevent overheating. Otherwise, a voltage input of 7 volts to 9 volts is recommended. The digital level translation jumper is set to 5 volts.

The second option (Model: 2M Arduino 818-3.7v) is the low voltage, low power option. With this option, the regulator is not included and the digital level translation jumpers are set to 3.3 volts. The intent of this option is to use it for weather, balloon, and remote applications where solar panels and a 1s lithium battery are the power source. In this case, the APRS position, weather, and telemetry reporting are used. The “Solar Power Pro Mini 1s” was designed for a low-power option- refer to the future product line for more information.

WARNINGS:

(1) Terminate the board with 50-ohm load or a suitable antenna.

(2) Do not use 2M Arduino 818-3.7v with the Arduino UNO board or equivalent. The 12 volts on the Vin pin will damage the components on the board.

(3) The 2M Arduino 818-12V board uses the LM1085IT-ADJ regulator which has overheating and over-current protection. If you plan to use the board in ambient temperatures of 100 F (38C) and above, consider using a voltage adapter to provide an output voltage of 7 to 9 volts. In all cases ensure that the unit is properly ventilated.

The “2M Arduino 818” board was designed around the flexibility of the SA181 transceiver module. With the 818-transceiver module, it can be programmed to different frequencies and transmission modes. The ability to change frequencies will accommodate different APRS areas and jurisdictions. Along with the APRS transmission mode, other modes such RTTY, SSTV, etc. could be used on different frequencies.

The board with the transceiver and sensors provides a compact system for vehicle, weather, and balloon applications.

The open-source Trackuino software has been modified to provide a weather packet frame, a telemetry packet frame, SA818 frequency configuration, and power management. The revised Trackuino version is the so-called “Trackuino 818 Plus”.

For additional software information and the software follow the link to: https://github.com/kghill/2M-Arduino-818

For questions and support contact us at catrackall@gmail.com

The open-source Arduino form factor makes it possible to use other compatible boards.