A-M Systems
2
131 Business Park Loop, P.O. Box 850 Carlsborg, Wa 98324
Telophone: 800-426-1306 * 360-683-8300 * FAX: 360-683-3525
E-mail: [email protected] * Website: http://www.a-msystems.com
STIMULUS:
This 5-pin connector enables an isolated stimulus source to be utilized to
pass current through the electrode while the channel is in Stimulate Mode. The pin
assignments are listed in the following table.
HEADSTAGE PROBE:
The
Headstage Probe has three
sockets and comes with
three wires that will connect these sockets to standard
electrode pins.
(the largest jack.. it accepts a 2mm
pin) is used to connect to the electrode (usually an high
impedance metal electrode).
REFERENCE-
is used to connect to
the indifferent lead. Either the
PROBE GROUND
connector or the
front panel
GROUND
must be connected for proper operation.
Usually the
PROBE GROUND
connector is tied to the indifferent
lead. If you desire to have the current constrained to a known
path you may want to place the
GROUND
elsewhere. Actual
GROUND
placement depends on the application.
MODE:
This rotary switch controls the operating mode for its
channel. The switch allows the user to select Record Mode
(
REC
) Stimulate Mode (
STIM
), or Impedance Check Mode
(
IMP
).
GAIN:
This rotary switch controls the level of signal gain for
its channel while the channel is in Record Mode. The switch allows the user to select
from
X100
,
X1000
, or
X10000
gain. This switch has no effect in Stimulate Mode and
Impedance Check Mode.
CAPACITY COMP:
This knob provides control over the amount of
capacitance in parallel with the electrode while the channel is in
Impedance Check Mode. Turning this knob clockwise decreases the
level of capacitance. With the electrode capacitance reduced, the
measured impedance will largely be a measure of the resistive
component of the electrode.
Warning: Turning the Capacity
Compensation too high will cause the circuit to oscillate wildly and
change frequency, and may also cause the electrode to behave in a
similar manner. The extreme swings
in voltage may be harmful to neural
tissue, and care should be exercised in using this control.
Pin
Location
Signal
A
upper left
+
B
upper right
-
H
middle
ground