Agilent Technologies E1445A, User'S Manual And Scpi Programming Manual

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Sweep time
specified
= Sweep repetition time
desired
* ((points - 1)/points)
Sweep Points Versus Time
In SWP_PVST (Sweep Points Versus Time) on page 136, the program
continually sweeps 100 frequency points in 0.125 seconds. To maintain this
rate continuously, the time between the last frequency point and the first
point is accounted for as follows:
Sweep time
specified
= 0.125 * (99/100) = 0.125 * 0.99 = 0.12375
Thus, the actual sweep time specified is 0.12375 seconds.
Frequency Lists Versus Time
In the LIST_TME program (Frequency Lists Versus Time) on page 139, the
program outputs a new frequency every 1 second. To maintain this rate
continuously, the time between the last frequency in the list and the first
frequency is accounted for as follows:
Repetition rate
specified
= 4 * (3/4) = 4 * 0.75 = 3
Thus, the actual repetition rate specified is 3 (seconds).
The minimum and maximum sweep times and frequency list repetition rates
are based on the number of points and frequencies, and are calculated as
follows:
MINimum = 1.25 mS * (points - 1)
MAXimum = 4.19430375 S * (points - 1)
Again, for continuous sweeping list repetitions, the desired (minimum or
maximum) time must be multiplied by the quantity:
(points -1)/points
The default sweep time is 1 second for any number of points or frequencies
specified.
The function in this program is a 1,000 point triangle wave. The maximum
frequency allowed in the frequency list is the reference oscillator frequency
divided by the quantity four multiplied by the number of waveform points:
Rosc/(4*npts) = 42.94967296E6 / (4 * 1000) = 10.7374 kHz
Chapter 4 Sweeping and Frequency-Shift Keying 159