Tabor 8020, Руководство пользователя

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is doubled. Amplitude control has no effect on the am-
plitude level at the SYNC output connector.
OFST - DC offset of the selected waveform at the main
output connector. Similarly to the amplitude, the offset
parameter is specified and accurately controlled only
when the output is terminated with 50 ohms. Offset con-
trol has no effect on the SYNC output connector.
WID - (Model 8021 only) The width parameter is com-
mon to the pulse and the ramp waveforms. When the
function generator is set to operate in pulse mode, this
parameter specifies the pulse width at the output connec-
tor. When the instrument is set to operate in ramp mode,
this parameter specifies the ramp width at the output con-
nector.
In pulse mode, the pulse width parameter defines the
time interval between two consecutive transitions; posi-
tive to negative transition in normal output mode or nega-
tive to positive transition in pulse complement mode.
The displayed and specified value is that obtained at the 50
% of amplitude setting.
The definition of ramp width is a little more compli-
cated because the edges are less defined. In this case the
specified and displayed ramp width value is that obtained
by the turn point of the edges - positive to negative turning
points in positive ramp output or negative to positive turn-
ing points in negative ramp output.
CARR - (Model 8022 only) Carrier defines the ampli-
tude of the output waveform signal when the function
generator is set to operate in its AM mode and when no
modulating signal is applied to the EXT. AM input con-
nector. The carrier level is specified as percentage of the
programmed amplitude value where 100 % carrier is
equivalent to 50 % of the displayed amplitude level.
The carrier signal is driven from a 50 ohms source
therefore, the value of the carrier parameter is specified
and accurately controlled only when the output is termi-
nated with 50 ohms. If the signal from the output connec-
tor is connected to an high impedance circuit, the actual
carrier level at the output connector is doubled. Carrier
control has no effect on the amplitude level at the SYNC
output connector.
STOP - Defines the sweep stop frequency. When the
function generator is set to operate with one of its sweep
modes, the waveform at the output connector sweeps
from frequency set by the FREQ setting to that set by the
stop frequency. In several sweep modes sweep stop may
change its function to sweep start. The programmed fre-
quency retains its value at both SYNC and the main out-
put connectors.
TIME - In linear sweep mode, sweep time determines
the time that it takes for completing one sweep cycle.
Sweep time is different for logarithmic sweep mode
where the specified value is that required for sweeping
one decade. The generator may be set to sweep over 10
decades. In that case, the sweep time should be multi-
plied by ten. Decade size ranges from 200 to 1999 counts
(or 20:1 if settings other than full and minimum scales
are required). If only part of the decade is being swept,
the sweep time is reduced proportionally.
Figure 3-1. Front Panel Controls, Indicators and Connectors
Operating Instructions Model 8020
Page 3-2