VHF Bird Alarm Transmitter
The BAT1 On-Off-Keying (OOK) transmitter is intended for the tracking of small animals such as birds and operates in the 150MHz and 173Mhz bands dependent on country specifics. It is designed to meet ETSI EN 300 220-2 radio standard.
- Standard frequencies in 150MHz to 173MHz bands.
- Other frequencies available subject to custom crystal lead times.
- Modulation OOK (on off keying).
- 2 modes of operation – Normal, Inactivity/Mortality.
- Low power requirements.
- Activity sensor.
- 2 grammes weight excluding coin cell
- Small tracking transmitters for game and wildlife research and management
- RF Power output: >-10dBm
Pulse width: 20ms
- Pulse rate: 40 pulses per minute (ppm)
- One-touch ON/OFF switching by magnet
- Tilt & Vibration sensor built in for mortality / inactivity detection
- Supply 3V lithium coin cell
- Battery life 12 months typical (dependent on model)
- Integral 30cm long nylon coated stainless steel wire antenna
- Microcontroller controlled
The BAT1 transmitter consists of an OOK modulated crystal Oscillator and frequency multiplier with two stage RF filter and antenna matching. It has a microcontroller, which controls the main functions of the transmitter. Activity monitoring is achieved by the use of an omni-directional tilt and vibration sensor, This senses movement regardless of orientation of the transmitter.
The transmitter has 2 pre-defined modes, Mode 1 is Normal Mode and transmits a single 20ms RF pulsed carrier and is repeated every 1.5 seconds. Mode 2 is controlled by the activity sensor, which is activated when the pre-determined activity timer has been exceeded, typically this will be 18 hours. When there has been no movement during this time, Mode 2 is then activated, this gives two 20ms transmitter pulses which are separated by 150ms, this gives the effect of a “double beep” on the Receiver and is repeated every 1.5 seconds. If any activity is detected when in Mode 2, the 18 hour counter is reset and then returns to Mode 1.
On board is a magnetically operated Single Pole Normally Open (SPNO) dry-reed switch and requires the use of a small magnet brought close to the unit to turn the transmitter on or off, no visual indication is provided as this would consume extra power and shorten the battery life for this reason a tracking receiver should be used to confirm if the transmitter is on or off.
Absolute maximum ratings
Exceeding the values given below may cause permanent damage to the module.
- Operating temperature -20C to +55C
- Storage temperature -30C to +70C
Performance specifications: (Vcc = 3V / temperature = 20C unless stated)