ADInstruments Bio Amp, Owner'S Manual

Page: 15 / 50

Chapter 1 Overview
15
it. If a status indicator does not turn on and stay on when the application
starts, it is most likely that the front-end is not connected properly.
Audio Out Socket
The Dual Bio Amp and Octal Bio Amp have audio monitor outputs on the
front panel that can be used with a wide range of headphones or externally
powered speakers. The 3.5 mm stereo socket provides two channels of sound,
one for each data channel. The audio output may be of use when monitoring
nerve firings to control the placement of electrodes, for instance.
The Back Panel
The back panel of the Bio Amp provides all the sockets required to connect
the front-end to the PowerLab and to other front-ends.
I
2
C Input and Output Sockets
Two nine-pin sockets are used to communicate with the PowerLab (they are
marked ‘I
2
C Bus’: a ‘bus’ is simply information-transmission circuitry such as
cables and connectors). These sockets allow multiple front-ends to be used
independently with one PowerLab. Power and control signals to connected
front-ends come from the PowerLab. ADInstruments front-ends are
connected to each other in series, output to input (this is discussed in more
detail in the next chapter).
Analog Output Sockets
The BNC sockets on the back panel of the Bio Amps provide the signal
outputs to connected analog input sockets of the PowerLab.
The sockets are labeled Signal Output on a single Bio Amp and Output 1 to
Output
n on a multi-channel Bio Amp. A BNC-to-BNC cable is supplied for
each connection. It is recommended that, to avoid confusion, you match the
Bio Amp output number with the corresponding PowerLab input connector.
If you are connecting to an earlier model PowerLab with differential inputs,
only connect the Bio Amp output to the positive analog input of the
PowerLab. ADInstruments applications do not find a front-end on start-up if
the negative input is used.
Audio Out Socket
The single Bio Amp has an audio monitor output on the back panel that can
be used with a wide range of headphones or externally powered speakers. The
3.5 mm stereo socket provides mono sound. The audio output may be of use
when monitoring nerve firings to control the placement of electrodes, for
instance.