When external interferences, for example heartbeats, muscle potentials, breathing, disturb the
measurements, both, the recording and the reference electrodes measure the same disturbance and the
noise signal is removed because only the difference between recording and reference electrode is digitized
and transmitted (Common Mode Rejection).
To make sure that the animal and the headstage are set to the same electrical potential, a ground
connection is also necessary. A good ground option is usually a large conductor, such as a scull screw
or a silver wire implanted under the skin of the animal.
Important: Please connect all unused inputs of the headstage to ground (GND) to prevent floating!
If you do not use all inputs of a headstage, for example, when using a headstage with eight channels
and a probe with four electrodes, the open channels are floating and disturb the recording of the
connected channels. It is necessary to ground the open channels physically. Deselecting the channels
in the “Hardware” tab of the software has no effect.
Positioning of the System Components
If possible, always provide a clear line of sight between the headstage and the receiver and keep the
distance as short as possible. In a larger cage, ideally position the receiver in the centre on top of the
cage. The position of the antennas does have an influence on the quality of the connection, so in case
of connection issues, it might help to play around with the antenna positions. Two out of five antennas
receive data from one transmitter on the headstage. One antenna is for metadata only. In theory, the
ideal position is if the two antennas of one receiver are orthogonal to each other, like in the image below.
However, as the signal is reflected by surrounding objects, the ideal position can be quite different in each
setup.
Optimizing Energy Consumption
The power consumption of the Wireless2100 headstage mainly depends on two parameters: The number
of channels and the sampling rate. To save power, the headstage automatically goes to standby mode
while not acquiring data. To decrease the power consumption while recording the most effective
measures are to decrease the sampling rate as far as possible and switch off channels with irrelevant data.
While not doing experiments, it is recommended to disconnect the battery or switch the headstage off via
software command. It is also possible to decrease the sending power of the transmitters, if the distance
between headstage and receiver is small.
Summary of Contents for Wireless2100-System
Page 1: ...Wireless2100 System Manual ...
Page 33: ...Datasheets ...