Solar PTTs | Battery Powered PTTs | Implantable PTTs
Solar PTTs, 45g and 95g Battery Powered PTTs, and Implantable PTTs are not equipped with GPS receivers, and therefore, their duty cycles are not synchronized with real-time clocks. Instead, they operate with a NANO timer that dictates the length of time a transmitter will be ON to transmit data, followed by a period of time during which the PTT will be OFF. The OFF periods allow Solar PTTs time to recharge their batteries, while the operational lifetimes of Battery Powered and Implantable PTTs are extended (by conserving power). READ MORE 
The NANO timer controls the intervals between transmissions. This transmission interval is allowed to drift slightly; consequently, the NANO timer cannot be used to command a PTT to turn ON at a precise time of the day. Nonetheless, we recommend programming PTTs with a duty cycle (one ON/OFF cycle) that is not a multiple of 24 hours in order to vary the time of day that a PTT is ON. The transmission interval's drift is gradual, so varying the time that a PTT is ON prevents transmissions from repeatedly occurring during a time window when there may be few satellite passes. The NANO timer resets to the beginning of the ON period when the magnet supplied with the PTT is placed over the STOP position of the PTT for at least one minute, then removed.
Please note that the Solar 2g PTT does not operate on a programmed duty cycle. Visit our Solar 2g PTT page for more information on how this unique PTT operates.
The tables below show the standard duty cycles for Solar PTT models and some suggested duty cycles for Battery Powered and Implantable PTTs. Duty cycles for Solar PTTs are appropriate for devices deployed where they will receive ample sunlight. If you are planning to deploy a Solar PTT in low-light conditions, please contact us to discuss a customized duty cycle. Battery Powered PTTs and Implantable PTTs are powered solely by primary lithium batteries; their duty cycles should be customized for each project in order optimize battery life. Please note that more frequent data transmission will shorten the operational lifetime of a battery-powered PTT.
| Transmitter Model | Standard Duty Cycle |
| Solar 5g, 9.5g, and 12g PTTs | 10 hours ON / 48 hours OFF |
| Solar 18g, 35g, and 50g PTTs | 10 hours ON / 24 hours OFF |
| Transmitter Model |
Transmission Lifetime |
Suggested Duty Cycle (for a 1 year deployment) |
Suggested Duty Cycle (for a 2 year deployment) |
| Battery Powered 45g PTT |
~1000 hours |
8 hours ON / 48 hours OFF | - |
| Battery Powered 95g PTT |
~2000 hours | 8 hours ON / 24 hours OFF | 4 hours ON / 48 hours OFF |
| Implantable 26g PTT |
~400 hours | 6 hours ON / 72 hours OFF | - |
| Implantable 38g PTT |
~750 hours | 6 hours ON / 72 hours OFF | - |
Multi-Season NANO Timer
Most PTTs that provide only Doppler locations are available with a multi-season NANO timer. This timer is pre-programmed to adjust the duty cycle of a transmitter to suit various phases of a study. Transmitters can be programmed with up to five different "seasons" of duty cycles with a maximum of 200 ON/OFF cycles each. If a transmitter is equipped with Ground Track (GT™), the user can also specify whether or not GT™ will be activated during each season. Keep in mind that NANO timer seasons are not determined by date and should therefore be coordinated with the deployment of the PTT. Upon reaching the end of the final season, the first season will begin again. The timer will also revert to the beginning of the first season if the supplied magnet is placed over the STOP position of the PTT for at least one minute then removed. READ MORE
To determine the length of a possible duty cycle season, use the following conversion formula or download our Duty Cycle Calculator. Please note that the duty cycle length calculated is an approximation and may vary slightly due to the previously mentioned drift in the transmission interval.
![[(number of ON hours + number of OFF hours) x (number of ON/OFF cycles)] / 24 = approximate length of duty cycle season (in days)](/uploads/MTI_DutyCycles_ConversionFormula.png)
Example: In a migratory bird study, a Battery Powered 45g PTT is programmed
with 4 duty cycle seasons. The PTT will begin with a conservative duty
cycle of 6 hours ON / 96 hours OFF for 15 cycles while the bird is nesting, then
change to a more intensive duty cycle of 8 hours ON / 24 hours OFF for 75 cycles around the anticipated start of migration. The duty
cycle will become conservative once more around when the
bird is expected to reach its wintering grounds and may not be making
significant movements, then switch again to an intensive duty cycle to follow the spring migration.
XT™ Programming
Our Solar PTTs (excluding the Solar 2g PTT) are available with an XT™ programming option. PTTs with this option will transmit during the OFF period of the duty cycle when their batteries are fully charged. These transmissions do not affect the ON/OFF programming of the duty cycle, but are intended to supplement the ON period transmissions when the PTT is in good lighting conditions. XT™ programming is especially useful for our smaller Solar PTT models which charge quickly in adequate lighting.
Solar Argos/GPS PTTs
Solar Argos/GPS PTTs are solar-powered devices with GPS receivers that operate using real-time clocks. Users must specify at which hour(s) of the day the PTTs should acquire GPS fixes and how often (in days) they should transmit the stored GPS data to Argos.
Solar Argos/GPS PTTs are available with multi-season duty cycle programming to accommodate various phases of a study. PTTs are programmable with up to five "seasons," defined by calendar dates (mm/dd), that will repeat annually. Each season can be designated with its own hours for data collection, interval between data transmissions, and whether or not Seasonal Ground Track (GT™) will be activated.
Battery Powered Argos/GPS 105g LC4™ PTTs
The 105g LC4™ PTT comes standard with a duty cycle of one GPS fix per day (at a user-specified time) and transmission to Argos every 10 days. Customized duty cycles are also available. Please note that more frequent data collections and/or transmissions will shorten the operational lifetime of the PTT.
GPS/GSM 20-70 Transmitters
GPS/GSM transmitters collect GPS data at intervals that adjust dynamically in relation to the transmitter's battery voltage. The rate at which a transmitter takes GPS fixes increases when battery voltage is higher and decreases when battery voltage is lower. During the day, GSM units take GPS fixes at a rate ranging from once a minute to every 2 hours. At night, the transmitter goes into a more conservative data collection mode during which the fix rate can extend from 0.5–4 hours. These data collection ranges can be modified if necessary.
GSM transmitters are programmed to transmit daily through the GSM network. If a transmitter is out of range of the network, or cannot connect to it for any reason, the unsent data remains archived until a future connection is made.
* SiV™ (Satellite-in-View) refers to a feature that activates the PTT only at times when satellites are most likely to be passing over the horizon and within view of the transmitter, therefore, maximizing data retrieval and saving battery power.
