The LB-2X is the smallest and lightest 2-stage transmitter currently commercially available. It is designed for glue-on attachment to small bats, small birds and large insects. The lighter weight of this transmitter now permits the tracking of smaller species than previously possible. The quoted weight is the total weight of the finished encapsulated transmitter, antenna and battery, ready to use in the field.


Model Weight Standard Life Lifespan range Dimensions LxWxH (mm)
LB-2X 0.27g 12 days 8-15 days 11 x 5 x 2.8 (see note below)
LB-2X 0.31g 21 days 13-22 days 11 x 5 x 2.8 (see note below)
LB-2X 0.41g 28 days 16-32 days 12 x 6 x 2.8 (see note below)

Note: As shown in the photo above, the battery can be placed on top of the transmitter, reducing the length by 4.5mm, and increasing the height by 1.0-2.0mm (depending on the battery used).

Frequency Range:  148, 149, 150, 151, 164, 165, 172, 173, 218, 219 & 220 MHz only.

Transmitter: Crystal controlled two-stage design, pulsed by a multivibrator.

Pulse Width (standard): 20 milliseconds.

Pulse Rate (standard): 40 pulses per minute (ppm). Available from 20-120ppm.

Housing: The transmitter and battery are encapsulated in an inert waterproof epoxy. Although the unit is usually glued to the animal (click here for gluing instructions), one tube can be attached for the passage of harness material or a suture. A tube will increase the total weight by ~0.05g.

Antenna: Single stainless steel wire, 0.007″ (0.18mm) in diameter, 14-16cm in length.

Activation: Soldering two wires starts the transmitter. Activation Instructions


Temperature (suffix “T”): An increase or decrease in temperature results in a corresponding increase or decrease in pulse rate. At the standard settings, the pulse rate changes from ~25 ppm at 0°C to ~40 ppm at 40°C. Each transmitter is supplied with a plotted calibration curve. This option adds ~0.05g to the finished weight of the transmitter.

Position (suffix “P”): The pulse rate switches from ~24 ppm in a vertical position to ~50 ppm in a horizontal position. This option adds ~0.5g to the finished weight of the transmitter.



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