Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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4-90 Input Configuration Menu
SR785 Dynamic Signal Anaylzer
Ground connects the shields to chassis ground with 50
Ω
. In this mode, do not exceed
3 V on the shields.
The impedance between signal input and chassis ground is always 1 M
Ω
.
Command: I1GD (?) {i}
Command: I2GD (?) {i}
Coupling
Select the Input Coupling for the selected input [DC, AC, ICP]. The Input indicator
shows the current coupling at the top of the screen.
The 3 dB bandwidth of the AC coupling is 0.16 Hz.
ICP coupling connects a 5 mA current source (26 VDC open circuit) to the center
conductor of the A input connector. This supply powers ICP accelerometers. The signal
is AC coupled from the center conductor. Set the Input Mode to A (not A-B).
Command: I1CP (?) {i}
Command: I2CP (?) {i}
Input Range
Select the Input Range for the selected input [-50 dBV .. +34 dBV]. The Input Range is
the full scale signal input just before overload.
The actual underlying Input Range of the SR785 varies by 2 dB steps from -50 dBVpk to
+34 dBVpk. The input range can be set in units of dBVpk, dBVrms, dBVpp, Vpk, Vrms,
dBEUpk, dBEUrms, dBEUpp, EUpk, EUrms, or EUpp. If a value is entered in one of
these units the closest actual hardware input range is selected.
The Input Range indicator shows the current range at the top of the screen.
Pressing this softkey turns off Auto Range for the selected input channels
If the input signal exceeds 35 dBV, the input range is automatically set to 34 dBV. The
range may not be changed while this HighV condition exists.
Command: I1RG (?) {i}
Command: I2RG (?) {i}
AA Filter
Select the Anti-Aliasing Filter for selected input [Off, On].
The anti-aliasing filter should generally be left On. Frequency domain measurements
may have spurious alias signals if the filter is Off.