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SI-2B & AI-2B |


These transmitters are designed for use as a backpack on waterfowl or large raptors.
Frequency Range: 138 to 235 MHz.
Transmitter: Crystal controlled two-stage design, pulsed by a CMOS multivibrator.
Pulse Width & Rate: 25 to 30 ms, nominal 0.7 p/s (42 p/m).
Specifications: (* = model shown above)| Model | Weight | Nominal Life | Lifespan range | Dimensions: L x Diameter (mm) |
| SI-2B* | 12g | 12 months | 6-18 months | 39 x 11 |
| SI-2B | 14g | 18 months | 12-24 months | 46 x 11 |
| SI-2B | 16g | 24 months | 12-30 months | 56 x 11 |
| AI-2B | 19g | 24 months | 12-30 months | 43 x 15 |
| AI-2B | 23g | 30 months | 18-36 months | 48 x 15 |
| AI-2B* | 30g | 36 months | 24-42 months | 49 x 17 |
Housing: Hermetically sealed cylindrical brass case. A foam pad is glued to the bottom surface of the unit to cushion it against the animal's body.
Attachment: For backpack application a brass tube is attached at each end for either a teflon ribbon or cable harness.
Antenna: Stranded stainless steel cable covered with a black nylon coating. Additional layers of shrinkable tubing reinforce the antenna at its base.
Activation:Removing an external magnet starts the transmitter. Replacing it stops the transmitter.
Mortality (suffix "M"): AI-2B only. The available delays are 4 or 12 hours. Note: The 4 hour delay is only available in the 30g size. The 4 hour delay circuit indicates its activation by a double pulse. The 12 hour delay circuit indicates its activation by increasing the pulse rate from a nominal ~42 p/m to ~75 p/m. After the mortality mode has been triggered, any motion resets the transmitter to the normal pulse rate. This option adds ~0.5g to the finished weight of each transmitter.