Product Manual

291, 292, 294
Users Manual
Note that the pulse-train waveform will continue to run from the internal clock until the
instrument receives the first rising edge of the external clock; at that point the hardware
switches over to the external source. In external clock mode the period of the pulse-train
waveform is determined by the number of points in the waveform multiplied by the
period of the external clock. The external clock period is determined by the user; the
number of points in the pulse-train waveform can be found, before selecting external
clock, by pressing the setup soft key beside pulse-train on the
STANDARD WAVEFORMS screen.
Waveform Hold in Pulse and Pulse-Train Modes
Pulse and pulse-train waveforms can be paused and re-started on any channel by using
the front panel
MAN HOLD key or by applying a signal to the rear panel HOLD IN
socket.
On multi-channel instruments the channels which are to be held by the MAN HOLD key
or
HOLD IN socket must first be enabled using the ARB HOLD INPUT screen,
accessed by pressing the
HOLD key:
ARB HOLD INPUT:
status: no hold
mode: disabled
Each channel is selected in turn using the channel SETUP keys and set using the mode
soft-key. The mode changes between disabled and enabled with alternate key
presses.
Pressing the front panel
MAN HOLD key stops the waveform at the current level on all
enabled channels; pressing
MAN HOLD a second time restarts the waveform from that
level. If the ARB HOLD INPUT screen is currently selected the status field will
change from no hold to manual hold while the waveform is paused.
A logic low or switch closure at the rear panel
HOLD IN socket also stops the waveform
at the current level on all enabled channels; a logic high or switch opening restarts the
waveform from that level. If the ARB HOLD INPUT screen is currently selected the
status field will change from no hold to ext hold while the waveform is
paused.
10-8