Signal Channel Output Filters - Ametek 7280 Instruction Manual

Chapter 6, COMPUTER OPERATION

6.4.03 Signal Channel Output Filters

NOISEMODE [n] Noise Measurement Mode control
NNBUF [n]
SLOPE [n]
6-14
The value of n sets the noise measurement mode according to the following table:
n Function
0 Noise measurement mode off
1 Noise measurement mode on.
When the noise measurement mode is turned on, the output filter time constant is
automatically adjusted until it lies in the range 500 µs to 10 ms inclusive, the
synchronous time constant control is turned off, and the output filter slope is set to
12 dB/octave if it had previously been 18 or 24 dB/octave.
Noise Buffer Length control
The value of n sets the noise buffer length according to the following table:
n Function
0 Noise buffer off
1 1 second noise buffer
2 2 second noise buffer
3 3 second noise buffer
4 4 second noise buffer
Output low-pass filter slope (roll-off) control
When the fast analog output mode and Noise Measurement mode are turned off
(FASTMODE 0 and NOISEMODE 0), the selection is according to the following
table:
n Slope
0 6 dB/octave
1 12 dB/octave
(TC ≥ 500 µs)
2 18 dB/octave
(TC ≥ 500 µs)
3 24 dB/octave
When:
a) The fast analog output mode is turned on (FASTMODE 1) and the instrument is
in single or virtual reference mode, or
b) Noise measurement mode is turned ON (NOISEMODE 1)
the selection is according to the following table:
n Slope
0 6 dB/octave
1 12 dB/octave