B&K Precision 4040A - Manual - Manual (Page 10)

10
CONTROLS AND INDICATORS
20. .START/STOP Switch. Enables adjustment of the starting
and stopping sweep frequencies. The actual adjustment is
performed by the SWEEP START and SWEEP STOP
controls (29 and 27). START/STOP selection is enabled
only when the SET/RUN switch (21) is set to SET.
21. RUN/SET Switch. Selects sweep set or sweep run
operation. In the SET position, the starting or ending
sweep frequency is continuously present at the output. In
the RUN position, the generator sweeps between the low
and the high frequencies at a rate set by the SWEEP
TIME control.
22. SWEEP EXT/INT Switch. When engaged (INT) enables
the sweep mode of operation. Sweep rate is controlled by
SWEEP TIME control (25) and sweep length is controlled
by the SWEEP STOP control (27) and the start frequency
is controlled by the SWEEP START control (29). When
released (EXT), allows external control of generator
output frequency by a DC voltage input at the VCG/MOD
INPUT jack (12).
23. SWEEP LIN/LOG Switch. When engaged (LOG) selects
logarithmic sweep characteristic and when released (LIN)
selects a linear sweep characteristic.
24. CNTR INT/EXT Switch. Selects the input source for the
counter input.
25. SWEEP TIME Control. In sweep mode, rotation
determines amount of time to sweep from the start
frequency to the stop frequency.
26. FINE FREQUENCY Control. Vernier adjustment of the
output frequency for ease of setting frequency.
27. SWEEP STOP Control. Adjusts the ending sweep
frequency.
28. COARSE FREQUENCY Control. Coarse adjustment
of the output frequency from 0.1 to 1 times the selected
range.
29. SWEEP START Control. Adjusts the starting sweep
frequency.
30. GATE LED. Indicates when the frequency counter
display is updated. When the 200K through 20M ranges
are selected, the LED will flash 10 times per second
(every 0.1 seconds). When the 20 through 20K ranges
are selected, the LED will flash once every second and
when the 2 range is selected, the LED will flash every 10
seconds. As the LED turns off, the display is updated.
31. Hz and KHz LED. Indicates whether the counter is
reading in Hz or KHz.
32. COUNTER DISPLAY. Displays frequency of internally
generated waveform, or external signal when CNTR
EXT is selected.
33. MODULATION ON/OFF Switch. Enables or disables
modulation of the generator.
34. MODULATION EXT/INT Switch. Selects whether
generator modulation is from the internal 1 KHz source
or from a signal applied to the VCG/MOD INPUT jack.
35. MODULATION FM/AM Switch. Selects Frequency
modulation or Amplitude modulation.
36. GCV OUTPUT. (Located on back panel) Generator
control voltage output. Voltage is proportional to the
generator frequency. When Sweep mode is selected
sweep voltage is present at this jack for connection to an
oscilloscope.