Axon Axopatch 200B, Theory Of Operation

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INSTRUMENT OPERATION • 65
Chapter 6
FREQUENCY TELEGRAPH
Provides a series of voltages that can be read by a computer to determine the
setting on the filter switch. The voltages and their associated frequency settings
are as follows:
Frequency (kHz): 1 2 5 10 100
Frequency Telegraph Voltage Output (V): 2 4 6 8 10
GAIN TELEGRAPH
Provides a series of voltages that can be read by a computer to determine the
setting of the gain switch. The gain takes
α
and
β
factors into account.
I (mV/pA): 0.05 1 0.1 1 0.2 1 0.5 1 2 5 10 20 50 100 2 200 2 500 2
V
m
(mV/mV): N/A N/A N/A 0.5 1 2 5 10 20 50 100 200 500
Telegraph Output (V): 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
These values have been chosen to fit in the range 0-10 V so that they can be read
on A/D converter channels of most computers.
I OUTPUT
Current output filtered at 10 kHz (3-pole Bessel). Gain is chosen by rear panel
switch to be
β
mV/pA or 100
β
mV/pA.
1 Applicable for
β
= 0.1 only
2 Applicable for
β
= 1 only