Ametek 7270 - Page 154

Chapter 6, COMPUTER OPERATION
6-16
TC [n]
TC. Filter time constant control
The value of n sets the output filter time constant in accordance with the following
table:
NOISEMODE
= 0
NOISEMODE
= 1
NOISEMODE
= 0
NOISEMODE =
1
n
time constant
time constant
n
time constant
time constant
0
10 µs
N/A
16
2 s
N/A
1
20 µs
N/A
17
5 s
N/A
2
50 µs
N/A
18
10 s
N/A
3
100 µs
N/A
19
20 s
N/A
4
200 µs
N/A
20
50 s
N/A
5
500 µs
500 µs
21
100 s
N/A
6
1 ms
1 ms
22
200 s
N/A
7
2 ms
2 ms
23
500 s
N/A
8
5 ms
5 ms
24
1 ks
N/A
9
10 ms
10 ms
25
2 ks
N/A
10
20 ms
N/A
26
5 ks
N/A
11
50 ms
N/A
27
10 ks
N/A
12
100 ms
N/A
28
20 ks
N/A
13
200 ms
N/A
29
50 ks
N/A
14
500 ms
N/A
30
100 ks
N/A
15
1 s
N/A
N/A means that n is an illegal value under these conditions.
The TC. command is only used for reading the time constant, and reports the current
setting in seconds. Hence if a TC 12 command were sent and the noise measurement
mode was turned off, TC would report 12 and TC. would report 1.0E-01, i.e. 0.1 s or
100 ms.
SYNC [n] Synchronous time constant control
n Effect
0 Synchronous time constant disabled
1 Synchronous time constant enabled. The actual time constant is recalculated
when the TC setting is changed, but not if the reference frequency changes.
2 Auto synchronous time constant enabled. The actual time constant is
recalculated when the TC setting is changed and also if the reference frequency
changes.
SLOPE [n] 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
2 18 dB/octave
3 24 dB/octave