The Thelma Biotel 9 mm acoustic transmitters are intended for use where both size, output power and long transmitting life is crucial. Manual tracking or automatic monitoring of larger salmon smolt migrating out fjords is a potential area of use. The customer specifies pulse delay or coded ID and type of encoding scheme, transmitting frequency and minimum and maximum random delay for ID transmitters.

The 9 mm transmitter is available with a wide range of power options for optimized battery life and power output. The 9 mm transmitter comes in two versions, the 9 and the 9L. 9L is intended for use where battery life is important, and 9 is ideal for use where size is prioritized. The full range of low, medium and high power output is available for both variations of the 9 mm tag.

Physical Properties of 9 mm Acoustic Transmitters
LP9L MP9 MP9L
Diameter [mm] 9 9 9
Length [mm] 24 24.4 29.4
Power output [dB re 1 uPa at 1m] 142 146 146
Weight in air [g] 4 3.6 5.2
Weight in water [g] 2.5 2.1 3.3
Estimated Battery Life for 9 mm Transmitters
Transmit Interval [sec] LP9L MP9 MP9L
30 11 months 137 days 7 months
60 18 months 7 months 13 months
90 23 months 10 months 17 months
120 27 months 12 months 21 months

The Thelma Biotel 9 mm acoustic transmitters are intended for use where both size, output power and long transmitting life is crucial. Manual tracking or automatic monitoring of larger salmon smolt migrating out fjords is a potential area of use. The 9 mm transmitters are delivered both as continuous pingers and ID transmitters. The customer specifies pulse delay or coded ID and type of encoding scheme, transmitting frequency and minimum and maximum random delay for ID transmitters.

Four versions of the 9 mm transmitters are available: LP9, MP9, MP9L, and HP, meaning low, medium, and high power, respectively.