BNC 835 User Manual - Manual (Page 18)

Berkeley Nucleonics Corporation 2955 Kerner Blvd., San Rafael, CA 94901
Phone: 415-453-9955, Fax: 415-453-9956, Email: [email protected], Web: www.berkeleynucleonics.com
modulation.
Figure 3-d CW Tab
3.6 Sweeps
Besides the basic CW operation, the instrument supports several sweeping modes. Sweep
parameters can be set in the SWEEP tab ( Figure 3-e ). Select frequency, power or list sweep by
clicking on the FREQ. SWEEP, POWER SWEEP or LIST SWEEP tab respectively.
3.6.1 Frequency Sweep
To start a frequency sweep,
a) enter start and stop frequency in Hz unit
b) enter the number of points (or points per decade)
c) enter the dwell time in milliseconds (min. dwell time is 50 microseconds)
d) enter the off time in microseconds
e) select the sweep mode as linear or log; additionally click “random” if random sequence is
desired
f) select the repetition mode: enter number of repetitions or choose “infinite”
g) select the ALC mode: on hold or off. Generally ALC on is used. If very short dwell times (1-2
ms) are needed, the ALC can be set to “hold”. In this way the ALC loop is disabled during the
sweep. The ALC voltages are calibrated before the sweep to maintain high level accuracy
during the sweep