SRS Labs SR430, Manual

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Mode Menu
Bin Width
This key is activated only when the Bin Clock Source is Internal. Press-
ing this key will activate the internal bin width entry field. The bin width
may only be adjusted using the knob. The available bin widths are 5ns,
40ns, 80ns,160 ns, ... , 10.486ms. 10ns and 20ns bins are not available.
Bins/Record
The Bins/Record key allows the knob to change the number of bins per
record. Numeric entry is not allowed in this field. The number of bins per
record is set in 1k (1024) increments from 1k (1024) to 16k (16,384).
This represents the maximum number of bins which can be displayed
and analyzed at one time. This limitation is due to the data display buffer
having a maximum capacity of 16k data points. The data acquisition
memory, however, can store up to 32,704 data points. Up to 32,704 bins
may actually be acquired and accumulated, of which, up to 16k bins may
be displayed at one time. The Trigger Offset determines how many bins
are skipped at the beginning of the total record before data is transferred
to the display buffer. A simple memory map is shown below.
Records/Scan
This key activates the Records per Scan entry field. Both numeric entry
and knob adjustment are allowed. The Records/Scan is the number of
records which will be accumulated before the data acquisition is DONE.
The Records/Scan may be programmed from 0 to 65,535. When set to 0,
accumulation will continue indefinitely until the [STOP] key is pressed.
This mode of operation is useful when setting up an experiment since the
BIN CLK OUT and SYNC/BUSY out will both be active indefinitely in-
stead of only until the scan is DONE.
The Records/Scan may be changed while data acquisition is in progress.
If the new value is less than the present number of records accumulated,
the scan will finish with the next record. If the new value is greater, then
accumulation progresses normally until the new number of records has
been acquired.
Trigger Offset
The Trigger Offset determines how many bins are skipped at the begin-
ning of the total record before data is transferred to the display buffer. Up
to 32,704 bins may actually be acquired and accumulated, but only a
maximum of 16k bins may be displayed at one time. The actual number
of bins which are stored in the data acquisition memory is equal to Trig-
ger Offset plus Bins/Record with a maximum of 32,704.
Trigger Offset
(0 to 16320)
Bins/Record
(1024 to 16384)
Data Acquisition Memory (32704)
Display Memory
(equal to Bins/Record)
Total Acquired Data