About batteries and lifetime calculation as a function of pulse - pause ratio:
Most of our transmitters use lithium 3.6 V batteries in different sizes and capacities. (Some models have 1 or 2 silver-oxide 1.5 V cells) Lifetime depends on installed battery capacity, the total power consumption of the transmitter (with options, if installed) over time, selfdischarge of battery (ok that´s not much) and also ambient temperature (extreme cold lowers capacity available). Now the RF signal of the transmitter is pulsing, assume it is a 10 mS (10 x 1/1000 second) pulse length and a 1200 mS pause length. Assume further that the battery has 1000 mAh capacity and the transmitter would have a power consumption, only in pulse periods, (in truth the MOS signal generator takes also around 2 µA permanently) of 10 mA, then you could divide the 1000 mAh through 10 mA to see the lifetime if the transmitter would transmit permanently, here 100 h. If you now divide the 100 h through the 10 mS of real transmitting time you get the amount of possible pulses. 100h are 60 x 60 x 1000 x 100 = 360.000.000 mS, divided by 10 mS = 36.000.000 pulses. In spite of any other power loss, the lifetime is 36.000.000 x pulse + pause time (what makes a complete cycle) = 36.000.000 x 1210 mS = 43.560.000.000 mS = that´s your theoretical lifetime, expressed in days approx. 504 days. Well that´s theory, in reality many other things affect lifetime, so as a rule of thumb in moderate ambient temperature take 75% of that, here 378 days. One now could think why shouldn´t we double lifetime by decreasing pulse length to 5 mS or doubling pause length to 2400 mS or double it again by both? The reason is because bearing of a signal becomes unpleasant with too long pauses and if the pulse is too short, most receivers come into trouble with signal detection and field strength measurement and you need that for bearing. Nevertheless all parameters can get specified by user without any change in price.
Below you can see the effect of the pulse-pause ratio. You can select the battery capacity. The assumed current consumption applies to 3 - 3.6V transmitters, and is lower for 1.5V transmitters. In this calculation the pulse current is 12 mA.
Transmitter options like activity and mortality indication
The activity detection changes the pause time between pulses. Depending on the position in the transmitter, a built-in tilt switch indicates, for example, that an animal has its head on the ground, showing it is eating.
Otherwise, an unsteady pause length indicates activity.
Mortality indication will also change the pause time for example the normal pause is 2000 mS now after 7 hours of no movement the pause changes to 1000 mS. After beeing moved again the pause falls back to 2000 mS. Mortality and activity indication can be ordered combined.