• Avian
  • Terrestrial

CTx Connectivity VHF tags

  • Product Type Icon Tag

Small VHF tags that last longer by saving energy when it is impractical to track them.

1 year operational life from 0.9g

CTx tags are an ideal solution for fine-scale studies of migration-connectivity, survivorship, breeding /wintering home range, or for researchers looking to make a small tag last longer. An onboard calendar allows you to choose your transmission days so you can optimise your data collection and track the bird manually while it’s within the study area.  To save energy, CTx tags will cease transmission when a bird is away on migration, which allows for sufficient power remaining to begin transmitting again upon the bird’s return.

Optionally, CTx tags can be paired with other Lotek products to enhance the scope of your study to encompass both localized movement and migration habits.


Sample Schedule:

  • Product Features

    • Custom calendar scheduling
    • Tags can be tailored for shape and attachment
    • Extended operational life by adjusting combinations of pulse rate and length
  • Product Applications

    CTx Connectivity tags have been used for investigating

    • Breeding or wintering site fidelity
    • Return dates
    • Retrieving archival loggers for data
    • Studies where continous tracking is not necessary

    These tags are also an effective solution for extending the study duration through strategic scheduling in order to prolong it’s operational life.

    Case Studies

    Stillman, A., Siegal, R., Wilkerson, R., Johnson, M., and Tingley, M. 2018. Age- dependent habitat relationships of a burned forest specialist emphasize the role of pyrodiversity in fire management. Journal of Applied Ecology 56: 880-890.

  • Product Specifications

    Model Minimum Weight [1] (g) Size [1] (LxWxH) (mm) Estimated tag life [2] (days) over 12 months
    20ms   48ppm 10ms   27ppm
    CTx (Ag376) 0.9 15 x 9 x 3 34 116
    CTx (Ag392) 1.2 16 x 9 x 4 63 210
    CTx (Ag393) 1.7 19 x 10 x 7 142 365

    1. Minimum weight and dimensions. Tags for some species require extra protection or attachment aids that can increase the weight and dimensions.
    2. Assuming the stated pulse length (milliseconds) and pulse rate (pulses per minute)

    Features and specifications subject to change without notice.


    The individual days that a tag will transmit on are factory-set during production, based on your choice of days.

    Models available in a variety of custom configurations. Please contact a Lotek Telemetry Specialist to discuss your needs.


    Technical Specifications:
    Operating temperature range: -10°C to +50°C
    Frequency Range: 138 MHz to 173.999 MHz

  • Product Downloads

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