A-M Systems 3000, Инструкция по эксплуатации

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A-M Systems
131 Business Park Loop, P.O. Box 850 Carlsborg, WA 98324
2
Telephone: 800-426-1306 * 360-683-8300 * FAX: 360-683-3525
E-mail: sales@a-msystems.com * Website: http://www.a-msystems.com
connected for proper operation. Usually the
PROBE GND
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
GND
elsewhere. Actual
GND
placement depends on the application.
Mode Controls
ELECTRODE TEST:
This toggle switch activates (
Ω
TEST
) a 2 nA p-p, 100 Hz
squarewave current source used to test electrode resistance and to adjust the
capacitance compensation. The
ELECT TEST
switch must be set to
Ω
TEST
and the
STIM-GATEREC
switch must be set to
REC
for the test signal to be monitored. (Note :
Recording and reference electrodes should be in a saline solution for resistance
testing
.) To accurately measure the impedance, verify at the
OUTPUT
connector that
the signal is a square wave of 100 Hz, adjust the
CAPACITY COMPENSATION
knob to
square the corners of the waveform. The amplitude of the square wave is a direct
measure of impedance in each of the six ranges (0.1Vp-p/M
Ω
, 0.2Vp-p/M
Ω
, 1Vp-
p/M
Ω
, 2Vp-p/M
Ω
, 10Vp-p/M
Ω
, 20Vp-p/M
Ω
).
STIMULUS:
This isolated BNC connector enables a stimulus source to be utilized to
pass current through the electrode while the unit is in stimulate mode (
STIM
). The
center pin of the BNC is the + input and the outer conductor is the - stimulus input.
When the unit is in the (
STIM ) mode the output will be a measure of the current
passing through the electrode in six ranges (5V/mA, 10V/mA, 50mV/µA, 0.1V/µA,
0.2V/ µA, or 1V/µA).
STIM-GATE-REC:
This toggle switch controls the operating mode for the Model 3000.
The switches allows the user to select Record Mode (
REC
) Stimulate Mode (
STIM
), or
Gate Mode (
GATE
).
Output
Output: This BNC connector provides the output signal from the amplifier.
GND:
This connector on the front panel provides access to the circuit ground. Either
the
PROBE GND
connector or the front panel
GND
must be connected for proper
operation. Usually the
PROBE GND
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
GND
elsewhere. Actual
GND
placement depends on the application. For low-noise
recordings a ground connection should be made in the recording medium (i.e. bath
ground, animal ground, etc.).
GAIN:
This rotary switch controls the level of signal gain for its channel while the
channel is in Record, Stimulate, and Impedance Mode. In Record mode (
REC
) the
switch allows the user to select from
X50, X100, X500, X1000, X5000,
or
X10,000
gain. In
Stimulate mode (
STIM
) the gain switch selects one six ranges (5V/mA, 10V/mA, 50mV/
µA, 0.1V/µA, 0.2V/µA, or 1V/µA). In Impedance test mode (
REC
,
Ω
TEST
) the gain