Ametek 7280 Instruction Manual page 213

FASTMODE = 0,
NOISEMODE = 0
n time constant
24 100 s
25 200 s
26 500 s
27 1 ks
28 2 ks
28 5 ks
30 10 ks
31 20 ks
32 50 ks
33 100 ks
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 15 command were sent and the noise measurement
mode was turned off, TC would report 15 and TC. would report 1.0E-01, i.e. 0.1 s or
100 ms.
TD Take data
Initiates data acquisition. Acquisition starts at the current position in the curve buffer
and continues at the rate set by the STR command until the buffer is full. If an
oscillator frequency and/or amplitude sweep has been defined and linked to the curve
buffer using the SWEEP command with a parameter of 9, 10 or 100, then this sweep
will be started as well.
TDC Take data continuously
Initiates data acquisition. Acquisition starts at the current position in the curve buffer
and continues at the rate set by the STR command until halted by an HC command.
The buffer is circular in the sense that when it has been filled, new data overwrites
earlier points.
TDT n Take data triggered
Sets the instrument so that data acquisition will be initiated on receipt of a trigger at
the TRIG connector on the rear panel. If an oscillator frequency and/or amplitude
sweep has been defined and linked to the curve buffer using the SWEEP command
with a parameter of 9, 10 or 100, then this sweep will be started as well.
Two triggered modes are possible, as set by the value of n:
n function
0 One complete curve or set of curves, each one consisting of the number of points
specified by the LEN command parameter, is acquired for each trigger.
1 One data point or set of data points is acquired for each trigger. Hence in order to
store a complete curve or set of curves, the number of triggers applied must equal
the number of points specified by the LEN command parameter. Note that in this
mode the maximum trigger rate is 1000 Hz and the storage interval control
setting has no effect.
VER Report firmware version
Causes the lock-in amplifier to respond with the firmware version number. The
Appendix F, ALPHABETICAL LISTING OF COMMANDS
FASTMODE = 1, FASTMODE = 0,
NOISEMODE = 0 NOISEMODE = 1
time constant time constant
100 s N/A
200 s N/A
500 s N/A
1 ks N/A
2 ks N/A
5 ks N/A
10 ks N/A
20 ks N/A
50 ks N/A
100 ks N/A
FASTMODE = 1,
NOISEMODE = 1
time constant
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
F-21