Wavetek 145 Instruction Manual page 18

Table 3-1. Period to Frequency Conversion
Time
.5
.6
.7
.8
.9
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
Converted Frequency Dial Values
(Based on f = 1/T where~)
lt--T4
Freq
Time
Freq Time Freq
2 2.3 .44 4.1
.24
1.67 2.4 .42 4.2 .24
1.43
2.5 .4 4.3 .23
1.25 2.6 .39 4.4
.23
1.11 2.7 .37 4.5 .22
1
2.8 .36 4.6 .22
.91 2.9 .35 4.7
.21
.83 3 .33 4.8 .21
.77 3.1
.32
4.9
.2
. 71 3.2 .31 5 .2
.67 3.3 .3
.63 3.4 .29
.59 3.5 . 29
.56
3.6
.28
.53 3.7 .27
Symbols
.5 3.8 .26
M 10
6
.48 3.9 .26
k 10
3
.46
4
.25
m 10-
3
µ 10-6
n
=
10-
9
To use the dial calibration marks when setting period time,
the period must be converted to frequency.
Example: Set generator for a 23 µs pulse period.
TRIGGER LEVEL Control
Determines the level at which the input trigger
signal at the TRIG IN connector
@
is accepted
as a trigger or gate in the trigger and gate modes.
The trigger level can be varied from fully cw, where
a positive-going excursion thru approximately -1 0V
is a trigger, to fully ccw, where a positive-going ex-
cursion thru approximately +10V level is a trigger.
@)
MANUAL TRIGGER Switch
3-2
Triggers or gates the ou~t signal when GENER-
ATOR MODE switch
~
is at TRIG or GATE.
ln trigger mode, one cycle is output when the
switch is pressed. In gate n:,ode, cycles are contin-
uously output as long as the switch is held down.
NOTE
Set TRIGGER LEVEL
@)
fully ccw.
1. Find the number 23 (or .23, 2.3, etc.) in the Time
column. Note its form and Freq equivalent.
Time
Freq
2.3 .44
2. Express 23 µs using the 2.3 form: 2.3 X 10-s.
3. Set FREQ/PERIOD MUL T switch to the equivalent of
10-
5
:
10µ.
n:n::o;
MULT lHz/ I
100
ll(
4. Set the dial to the frequency equivalent of 2.3: .44 .
\ \ I
w/
I
\ \ 4 / /
/''- '1 •
20·6 /
/ • 'i:15) • ,,
NOTE: Refer to paragraph 1.2 for dial accuracy.
®
PULSE DELAY Control
When NORMAL/DOUBLE/DELAYED switch®
is at DELAYED, PULSE DELAY selects one of six
time ranges for delay of pulse with· respect to the
undelayed signal leading edge. When
@
is at
DOUBLE, PULSE DELAY selects the time between
double pulse leading edges.
VARIABLE Control
Inner knob selects delay time within the range
selected by the outer knob.
®
NORMAL/DOUBLE/DELAYED Switch
Selects the pulse parameters as follows:
NORMAL - Pulse of width and frequency set by
front panel switches appears at TTL, TTL, ECL,