Ametek 7270 Instruction Manual page 149

Note that the IMODE command takes precedence over the VMODE command.
DEMOD2SRC [n] Second stage demodulator signal source
In the dual reference mode, the value of n sets the source of the signal for the second
stage demodulators according to the following table:
n Signal source
0 Main signal channel ADC (i.e. both demodulators are fed the same signal)
1 ADC1 - rear panel auxiliary ADC input
2 Demodulator 1 X channel output - this is the Tandem demodulation mode
FLOAT [n] Input connector shield float/ground control
n Selection
0 Ground
1 Float (connected to ground via a 1 k resistor)
FET [n] ] FET input selection
The value of n controls the input device used at the signal input according to the
following table:
n Input device
0 Bipolar
1 FET
DCCOUPLE [n] Input coupling control
The value of n sets the input coupling mode according to the following table:
n Coupling mode
0 AC coupled
1 DC coupled
SEN [n]
SEN. Full-scale sensitivity control
The value of n sets the full-scale sensitivity according to the following table,
depending on the setting of the IMODE control:
n
IMODE=0
1 2 nV
2 5 nV
3 10 nV
4 20 nV
5 50 nV
6 100 nV
7 200 nV
8 500 nV
9 1 µV
10 2 µV
11 5 µV
12 10 µV
13 20 µV
14 50 µV
15 100 µV
16 200 µV
Chapter 6, COMPUTER OPERATION
full-scale sensitivity
IMODE=1
2 fA
5 fA
10 fA
20 fA
50 fA
100 fA
200 fA
500 fA
1 pA
2 pA
5 pA
10 pA
20 pA
50 pA
100 pA
200 pA
IMODE=2
n/a
n/a
n/a
n/a
n/a
n/a
2 fA
5 fA
10 fA
20 fA
50 fA
100 fA
200 fA
500 fA
1 pA
2 pA
6-11