.. _tethers: ##################### Coaxial Tether ##################### .. image:: /_static/images/minicoax_tether.webp :alt: image of a coaxial tether :align: center The Miniscope v4 requires a single 50Ohm coaxial tether for power, communication, and data transmission. This tether needs a Hirose U.FL connector to connect to the miniscope end and an SMA connector for connection to the rest of the system. The standard option supplied in the Open Ephys store is a 1.1 mm diameter tether of 1.5 m in length. The length and diameter of the tether used can vary, but the associated voltage drop has to be accounted for to maintain the device within the operating voltage range as described in the :ref:`measure_voltage` section. Longer or thinner tethers can require externally adjusting the power supplied to the Miniscope DAQ, as discussed in the :ref:`externalpower` section. Compatible commutators can be used to prevent tether twisting, as explained in the :ref:`commutators ` section.