1. General provisions and purpose of the device
The tBeacon Black electronic autonomous radiolocation module is designed to coordinate the location, monitoring and operational search of valuable moving objects in open terrain. The main civilian purpose of the complex is technical supervision and evacuation of unmanned environmental and meteorological monitoring drones, unmanned sprayers, civil agricultural drones, autonomous weather probes, as well as valuable property in difficult terrain conditions.
For full interaction with the module, standard radio transceivers (radio stations) of the civil LPD, PMR, FRS bands or amateur radio communication systems of the decimeter band (UHF, 70 cm) are used. It is recommended to use radio stations that support hardware generation of a call with a frequency of 1750 Hz (Tone burst) or work with low-frequency subtones of the CTCSS system. The device is compatible with most common civil transceivers (in particular, the Baofeng UV-5R, UV-3R, Yaesu series and analogues).
The complex provides several alternative object localization algorithms:
- Voice telemetry navigation: The module automatically broadcasts the current geographical coordinates received from the integrated satellite receiver.
- Classic direction finding mode: Determining the direction to the signal source using directional antennas or the shielding method in the absence of current satellite data.
- Digital Tactical Proximity Mode: Reverse radio direction finding with automatic voice report of signal level directly on the air.
- Non-volatile coordinate memory: In the event of a critical failure or loss of power to the satellite receiver after an incident, the device captures and transmits the last valid coordinates from internal flash memory.
- Light and sound verification: Connection of additional peripheral modules for visual and acoustic detection of an object in dense vegetation or snow cover.
2. Regulatory and legal regulations for the use of radio frequency spectrum
The operation of the radio detection module must be carried out in strict accordance with the current legislation and radio frequency resource allocation rules of your country. The user is fully responsible for the selection of the operating frequency. The factory default frequency may be restricted for free use in your administrative area.
When operating in unlicensed bands (LPD, PMR, FRS), observe the established power limits and transmission time regulations. In case of configuring the device for amateur radio frequencies, the user is obliged to have the appropriate permission (license) and ensure periodic broadcasting of his own call sign on the air in accordance with the requirements of radio communication. A mandatory rule of technical ethics is preliminary monitoring of the selected channel for its occupation by other civil services.
3. Strategy and technical methods for searching for objects
3.1. Satellite radiolocation (GPS navigation)
The most effective and fastest evacuation algorithm. After remote activation, the module broadcasts the current or last saved geographical coordinates of the object. The operator records the digital data and, using any available navigation equipment (smartphone, portable navigator), heads to the specified point.
To work offline on mobile devices, it is recommended to use cartographic software with support for topographic maps (Androzic, TwoNav, etc.) or specialized utilities with a vector direction and distance indicator (GeoCompass for Android OS or iArrow for iOS).
⚠️ Critically important: Before going out into the field, check that the mathematical format of the coordinates displayed in your navigation application fully matches the format set in the module’s internal configuration parameters!
3.2. Tactical Proximity search mode
This algorithm implements the principle of radio direction finding “in reverse.” The module independently measures the amplitude and quality of the signal coming from the operator’s radio, converts it into a digital scale (from 0 to 99 conventional units, where 99 is the maximum power) and instantly announces this value in a voice over the radio.
Proximity mode operation algorithm:
- The operator sends a short call signal on the operating frequency.
- The module fixes the signal level, sounds it and goes into standby mode. If there is no repeated request, the device returns to the standard cycle of transmitting coordinates and three-tone markers.
- In the event of a repeat call, the module activates a high-speed “request-response” cycle, instantly reporting the communication level.
- Tactics of taking a bearing: The operator presses the radio tightly to the body (using it as a natural screen for radio waves) and slowly rotates around its axis 360°, periodically sending a call. It is necessary to fix the direction in which the smallest digital reading is received. The exact direction to the object will be behind the operator’s back. A similar procedure is performed using directional Yagi antennas.
3.3. Classical radio direction finding:
The method is used in the absence of satellite data or when switching to work with the radio station’s S-meter. The special three-tone signal generated by the module consists of three consecutive pulses of different hardware power:
- First tone: 100 mW (maximum power for long-range detection).
- Second tone: 13 mW (average power for medium distances).
- Third tone: 1.3 mW (minimum power for accurate localization within a radius of several meters).
By estimating by ear or using instruments the number of audible tones and their volume while rotating the antenna (or shielding with the body), the operator constructs bearing lines on the map and determines the intersection point.
4. Operation and logic of the module
After power is applied, the device initiates an acoustic verification siren (or broadcasts a Morse code call sign) and broadcasts the current voltage of the internal lithium-polymer battery.
If the connection architecture provides for monitoring of an external power battery (LiPo), the device indicates the automatically recognized number of power cells (cans) with a series of short beeps, and then announces the average voltage per cell.
After completing the start-up protocol, the module enters a power-saving “deep sleep” mode, cyclically waking up for short periods of time to scan the radio air and read data from the satellite navigation chip.
For visual control, three LED indicators are integrated on the board:
- 🟡 Yellow: Active charging process of the built-in battery from the on-board network of the object.
- 🟢 Green: System health timer (blinks once per second). To maximize battery life, it automatically turns off after 8 hours of continuous operation.
- 🔴 Red: Active interaction indicator – flashes during radio transmission, GPS data exchange, or air scanning.
In standby mode, the module is completely passive, does not broadcast anything and does not create any interference with other onboard automation or the object’s telemetry.
4.1. Power management
- Manual start: Short press (0.5 sec) on the mechanical or external button. Confirmed by a sound signal and a start message on the air.
- Automatic start: Occurs instantly when power is applied to the microUSB connector. For integration into the board without data transfer, it is enough to connect two wires to the connector: GND and +5V.
- Shutdown / System reset: Long press the power button (at least 5 seconds).
4.2. Activation by remote call
Remote wake-up of the module is carried out by broadcasting a call of a certain frequency. The priority is to use the standard tone of 1750 Hz (Tone burst). In the absence of technical support for this tone on your radio, it is allowed to use analog subtones of the CTCSS system (the subtone is activated exclusively for transmission on the radio).
After successfully detecting a call signal with a duration of at least the set listening interval (by default 3 seconds), the module performs the following operations:
- Broadcasts the exact level of received call power.
- Activates peripheral light and sound signaling (if the signal level is above the set safe threshold).
- It sequentially transmits three tones of decreasing power (100–13–1.3 mW).
- Synthesizes the current geographic coordinates of the object by voice.
⚠️ Please note: Using CTCSS increases the risk of false alarms due to interference on the air. When setting subtones, it is recommended to choose the highest possible frequencies (for example, 240 Hz), since detecting low frequencies requires an increase in the air analysis time and increases the device’s power consumption.
4.3. Activation by internal alarm timer
If the radio does not support tone calls, the module can be configured to start autonomously by time using the “Initial delay” parameter. After the specified time from the moment of switching on, the device automatically exits sleep mode and begins to cyclically broadcast three-tone markers and current coordinates with a specified periodicity interval.
🛑 Important: The module activated by a timer completely ignores external radio calls from walkie-talkies.
4.4. Contactless shutdown of hidden modules
In the case of monolithic installation of the device inside sealed housings or wings, where there is no physical access to the shutdown button, a safe contactless shutdown algorithm has been implemented.
Shutdown procedure:
- Send a call from a walkie-talkie in close proximity to the module antenna.
- Wait for the device to give a voice verification command in a countdown: “3-2-1-0”.
- Send a repeat call signal immediately.
- The function is activated only if both signals are received by the module with a maximum communication amplitude of 99 (available for hardware versions Amber ≥ 6.7 and Black ≥ 7.7).
5. Engineering integration and mechanical installation
Для стабільної автономної роботи модуль комплектується індивідуальним елементом живлення — однією коміркою LiPo акумулятора ємністю від 50 до 300 мАг.
Installation and protection rules:
Mandatory technical regulations: To protect against moisture, dew and dirt, cover the board with specialized electrical insulating varnish and place it in a protective transparent heat-shrink tube.
- Choose areas within the object’s body that are least prone to deformation, impact, and breakage during a hard landing.
- The electronic board must be completely insulated from any conductive, metal or carbon surfaces.
- The radio module antenna should be located vertically, as far away as possible from the power frame elements, wiring, and carbon parts.
- ❌ It is strictly forbidden to shield or cover the area where the ceramic GPS satellite antenna is located on the device board with radio-impervious materials (carbon fiber, metal, foil)!
6. Connecting external light and sound peripherals
To facilitate the search for an object at the final distance (in deep snow or tall grass), additional power notification elements can be connected to the AUX outputs. By default, the configurator assigns: Pin 5 for a pulse flash, Pin 6 for an acoustic buzzer (siren).
When the emergency mode is activated, a high logic level is applied to the flash output, and rectangular pulses of a given frequency corresponding to the SOS code are applied to the siren output.
⚠️ Technical limitation: The maximum direct current from the processor logic pins is limited to 30–40 mA. Connecting powerful LEDs or sound sirens with higher current consumption should be done exclusively through an external transistor switch (MOSFET field effect transistors) according to the recommended scheme.
7. Service, calibration and adjustment
All commissioning, parameter changes, log reading and firmware updates are performed via the utility (configurator) on a PC using a standard USB-microUSB cable. The USB-UART interface drivers for the CP210x chip must be installed on the computer.
7.1. Frequency Calibration Procedure
Each transceiver module undergoes initial factory setup, however, to compensate for temperature drift of the quartz resonator and achieve perfect synchronization with your specific radio, it is recommended to perform individual calibration.
Calibration algorithm:
- Establish a connection to the configurator, select the appropriate COM port and press the “FREQUENCY CALIBRATION” button.
- Set the radio to the same operating frequency as the module.
- After starting the procedure, press and hold the call button (Tone burst or CTCSS) on the radio and continuously hold it on the air until the process is complete (about 30–40 seconds).
- Do not interrupt the signal and do not bring the radio antenna closer than 1–2 meters to the beacon board and PC during calibration to avoid overloading the receiver input stage!
7.2. Unloading and flight track analysis
The module cyclically records the coordinates of the model’s movement into the internal non-volatile flash memory at a specified time interval. This information allows you to reconstruct the object’s movement trajectory in detail and analyze the causes of the incident.
Data is uploaded by clicking the “DOWNLOAD TRACK” button in the configurator. The file is saved in the international cartographic format .KML and can be instantly imported for visualization in Google Maps or Google Earth.
8. Modular description of system configuration parameters
8.1. Basic radio path settings
- Operating Frequency (Hz): The exact frequency of the transmitter in Hertz. For example, the first channel of the LPD grid (433.075 MHz) is written in the field as 433075000. The main license-free channels are available in a convenient drop-down menu of the configurator.
- Frequency Correction: An individual hardware receive/transmit correction factor that is calculated automatically during the calibration procedure with your radio.
8.2. Налаштування автономного таймера
- Initial delay (sec): The waiting time before the timer mode automatically starts. A value of 0 completely disables the standalone timer.
- Interval at start/end (sec): Determines the frequency of going on air at different stages of the search period (default: 10 sec at start and 60 sec at end to preserve remaining battery capacity).
- Search period (min): Total time of active transmission of timer mode signals (default 240 min = 4 hours).
- Delay to next period (min): The time the device will sleep between activity cycles (default 1200 min = 20 hours). This algorithm allows the module to save battery power and wake up at the same time the next day.
8.3. Call settings and listening to the broadcast
- Listening interval (sec): The frequency at which the sleeping module turns on the radio to check for a call from the operator’s walkie-talkie (default 3 sec). Low values significantly increase power consumption. To ensure the device wakes up, the duration of the call signal from the walkie-talkie should be slightly longer than this parameter (3–4 seconds).
- Listening period (msec): The net time of the air analysis during wake-up (default 50 ms). Increasing the parameter increases the accuracy of weak call recognition, but proportionally consumes battery power. When working with analog CTCSS subtones, this parameter must be forcibly increased to the minimum value of 150 ms (calculated by the formula: 30000 / subtone frequency in Hz).
- Number of duty cycles / Packet interval: Adjusts the number of automatic response packets (tone + voice) after detecting a single call and the time pause between them.
8.4. GPS satellite module parameters
Modern navigation chips consume a significant current (about 30 mA), so in order to maintain power autonomy, voltage is supplied to the satellite receiver only at fixed intervals of 5 minutes in the following cases:
- If there is a stable external on-board power supply (GPS is active constantly + 5 minutes after the on-board power is cut off).
- During the initial manual or automatic device power-up (to successfully perform the “cold start” procedure).
- When receiving any remote call from the radio. Updating the coordinates each time extends the GPS operation for another 5 minutes. The module broadcasts the time until navigation is turned off with a minute-by-minute countdown.
- GPS Error Limit: The maximum number of errors allowed when reading NMEA data packets. After reaching the limit (default 100), the device determines that the communication lines with the navigation chip are physically broken or damaged and reduces the frequency of requests to the port by 100 times.
- Coordinate format: Specifies the mathematical form of the geodata translation (the recommended default civil standard is YY.YYYYYY, which provides accuracy up to 1 meter and is instantly recognized by Google Maps).
- Minimum Satellites: Data validity threshold (default 3). The module will update the coordinates in flash memory only when the chip sees more satellites than specified in the settings. A value of 0 allows you to receive any information. When using the NMEA RMC protocol, there is no information about the number of satellites, so any non-zero value of the parameter will ignore this protocol.
8.5. Special and service parameters
- Порог вкл. сирены и вспышки: Рівень RSSI зв’язку, вище якого пристрій задіє підключену світлозвукову периферію для ближнього пошуку в траві. Щоб вимкнути AUX-сигналізацію, введіть значення 100, для постійної роботи за будь-якого сигналу — 0.
- Callsign: Enter your official technical or amateur radio identifier. The code is automatically broadcast in Morse code over the air with a probability of ~1/2 during each coordinate transmission.
- Battery Life Extension: Automatic intelligent monitoring of the remaining capacity of the built-in battery. Forcibly turns off the device in case of voltage drop to a critical minimum, preventing irreversible degradation and swelling of the LiPo cell. If the option is disabled, the module will work until the last second, completely discharging the battery (available for hardware versions Amber ≥ 6.7 and Black ≥ 7.7).
