MOGlabs ARF021 Manual page 94

84
This has the effect of restricting the smallest and largest changes
that can be made in parallel frequency mode through the associ-
ated frequency discretisation (step size) and value range. If large
changes to frequency are required, high gain should be used. If high
resolution is required, small gain should be used. The outcome of
different gain settings are shown in Table 9.1.
Gain Step
0 0.23 Hz
1 0.47 Hz
2 0.93 Hz
3 1.86 Hz
4 3.73 Hz
5 7.45 Hz
6 14.9 Hz
7 29.8 Hz
Table 9.1: Effect of frequency gain with default clock configuration.
The gain is specified initially using the
TABLE,XPARAM,ch,FREQ,gain
ch
where is the channel and
The range of frequencies that can be achieved in advanced table
±
mode is
0 max
FREQ
command, and
sponding to the gain. To assist with understanding these ranges,
TABLE,XPARAM,ch,FREQ
the
what combinations are possible for the current set of parameters.
Note that the frequency gain can presently only be set before the
table is populated, and cannot be changed mid-sequence. It is there-
fore important to ensure that the desired frequency range fits entirely
within the accessible range.
Chapter 9. Advanced table mode (XRF)
Max Gain
7.54 kHz 8
15.3 kHz 9
30.5 kHz 10
61.0 kHz 11
122 kHz 12
244 kHz 13
488 kHz 14
977 kHz 15
gain
is the desired gain (0-15).
where is the center frequency set with the
0
is the value in the above table corre-
max
command will output information about
Step Max
59.6 Hz 1.95 MHz
119 Hz 3.91 MHz
238 Hz 7.81 MHz
477 Hz 15.6 MHz
953 Hz 31.2 MHz
1.91 ˙ kHz
62.5 MHz
3.81 kHz 125 MHz
7.63 kHz 250 MHz
TABLE,XPARAM
command,