User Manual LW120
this number to program the deviation range. We want the front
panel output to deviate by 100 KHz, 50 KHz above and 50 KHz
below the carrier frequency. Since the deviation range is
controlling sample clock, the value that you have to put on the
display is 100 KHz x 64 = 6.4 MS/s
8. Use the cursor to point to the digit you want to change and
rotate the dial to adjust the display to 6.4 MS/s
9. Select the Freq parameter. This parameter sets the modulating
frequency. There is no need to compute and convert this
parameter because the frequency is given in units of Hz.
10. Use the cursor to point to the digit you want to change and
rotate the dial to adjust the modulating frequency to 100 Hz
11. You may press More to access triggered FM modes, or set
marker position
!
50
TTL
POWER
I
0
OUTPUT
LeCroy
MODEL
100 MS/s ARBITRARY WAVEFORM
!
50
CHAN
1
SYNC
CHAN
2
RESET
CURSOR
MAN
TRIG
TRIGGER
AMPLITUDE
FREQUENCY
UTILITY
WAVEFORM
8
10
9,11
Figure 3-20. Programming Standard FM Mode Parameters
Wave SIN
Dev 6.400000MS/s
Freq 100.0000Hz
Back
If you did not make any programming errors, the front panel outputs
will generate frequency modulated waveforms having carrier
frequency of 1 MHz, deviation frequency of 100 KHz and
modulating frequency of 100 Hz.
We’ll now check the results at the rear-panel sine output connector
and compare what we get there to what we see on the front panel.
Remove the cable from the main output connector and connect to
the rear-panel SINE OUT connector. Here is what you should
expect to see when you check this output:
1. Carrier is sine waveform with fixed amplitude level of 1V
into 50
Ω
.
2. Carrier frequency is 64 MHz
3. Deviation range is 3.2 MHz above and 3.2 MHz below
the carrier
4. Modulating waveform is sine waveform and modulating
frequency is 100 Hz.
Using The Instrument 3-24