Operation - Wavetek 801 Instruction Manual

The OUTPUT NORM/COMP switch could also be used to
reverse the upper and lower levels as the trigger edge does,
but some error could be introduced by the X-Y multiplier.
Rise Time Measurements
3.2.9
When measuring rise time in a linear device under test, the
error induced by the rise time of the testing system must be
considered. For exam pie, when
1 rise time
on an oscill oscope, 80
observed
O f
' 801 =
That is, the observed rise time must be corrected for by the
inherent oscilloscope rise time to determine the actual 801
rise time. Extending the method to include a circuit under
test will determine circuit under test rise time:
observed = 801

3.3 OPERATION

In the following descriptions of operation, observe the
pulse on an oscilloscope. When the 5Oa OUT pulse is not
desired, disregard leading and trailing edge adjustments.
(See figure 3-2 for pulse parameters.)
Continuous Pulses
3.3.1
Set the controls as follows for continuous pulse output.
Operation
Control
MODE CONT
NORM (or COMP if inverted pulse is
OUTPUT
desired)
Set as desired. DELAY is constrained to
All Other
be less than PERIOD-(WIDTH +TRAIL-
Controls
ING EDGE). If a large pulse WIDTH is
desired but cannot be obtained, refer to
paragraph 3.3.2.
Continuous Wide Duty Cycle Pulses
3.3.2
Follow this setup for pulses greater than those that can be
obtained in paragraph 3.3.1. The " pulse" that appears to be
positive going is referred to as the > 70% pulse.
rving the 801 rise time
obse
is
= t2
+ t2
scope 801
observed scope
+ t2 + t2
c.u.t.
scope
Control Operation
MODE CONT
OUTPUT COMP
PERIOD/RATE Set as desired.
and Level Con-
trols
W IDTH Set to desired lower level time (see
figure 3-4). The > 70% pulse will start
W IDTH time after SYNC leading edge
with DELAY OFF.
S Y N C
COMPLEMENT
Figure 3-4. Greater Than 70% Duty Cycle Pulse
Control Operation
Edge Controls Set as desired.
and DELAY
3.3.3 Triggered Pulses
Set up as in paragraph 3.3.1. If triggering with an external
signal, connect the trigger source to TRIG INPUT. Ensure
that the trigger rate is slower than the pulse rate.
Control Operation
TRIG
MODE
TRIGGER Set as desired. (Observe TRIG indicator
to ensure triggering occurs.)
3.3.4 Gated Pulses
Set up as in paragraph 3.3.1. If gating with an external sig-
nal, connect the gate source to TRIG INPUT. Set the gate
pulse width to allow the number of pulses desired. Reset
the controls as follows.
Control Operation
MODE GATE
TRIGGER Set as desired. (Observe TRIG indicator
to ensure triggering occurs.)
C Y C L E PULSE
3-5