650
Chapter 18
Troubleshooting
Basic Signal Generator Operations
No Modulation at the RF Output
Check the
MOD ON/OFF
annunciator on the display. If it reads
MOD OFF
, press
Mod On/Off
to toggle the
modulation on.
Although you can set up and enable various modulations, the RF carrier is modulated only when you have
also set
Mod On/Off
to On.
On the E4438C for digital modulation, make sure that
I/Q Off On
is set to On.
Sweep Appears to be Stalled
The current status of the sweep is indicated as a shaded rectangle in the progress bar. You can observe the
progress bar to determine if the sweep is progressing. If the sweep appears to have stalled, check the
following:
❏
Have you turned on the sweep by pressing any of the following key sequences?
Sweep/List
>
Sweep
>
Freq
Sweep/List
>
Sweep
>
Ampl
Sweep/List
>
Sweep
>
Freq & Ampl
❏
Is the sweep in continuous mode? If the sweep is in single mode, be sure that you have pressed the
Single Sweep
softkey at least once since completion of the prior sweep. Try setting the mode to
continuous to determine if the missing single sweep is blocking the sweep.
❏
Is the signal generator receiving the appropriate sweep trigger? Try setting the
Sweep Trigger
softkey to
Free Run to determine if a missing sweep trigger is blocking the sweep.
❏
Is the signal generator receiving the appropriate point trigger? Try setting the
Point Trigger
softey to Free
Run to determine if a missing point trigger is blocking the sweep.
❏
Is the dwell time appropriate? Try setting the dwell time to one second to determine if the dwell time was
set to a value which was too slow or too fast for you to see.
❏
Do you have at least two points in your step sweep or list sweep?
Cannot Turn Off Sweep Mode
Press
Sweep/List
>
Sweep
>
Off
.
In the sweep mode menu you can choose to set the sweep to various sweep types or to turn sweep off.
Summary of Contents for E4428C
Page 22: ...Contents xxii ...
Page 224: ...200 Chapter 4 Basic Digital Operation Creating and Using Bit Files ...
Page 228: ...204 Chapter 5 AWGN Waveform Generator Configuring the AWGN Generator ...
Page 229: ...205 6 Analog Modulation ...
Page 276: ...252 Chapter 7 Digital Signal Interface Module Operating the N5102A Module in Input Mode ...
Page 286: ...262 Chapter 8 Bluetooth Signals Turning On a Bluetooth Signal ...
Page 330: ...306 Chapter 9 BERT Verifying BERT Operation ...
Page 366: ...342 Chapter 10 CDMA Digital Modulation IS 95A Modulation ...
Page 394: ...370 Chapter 12 Multitone Waveform Generator Applying Changes to an Active Multitone Signal ...
Page 468: ...444 Chapter 15 W CDMA Digital Modulation for Component Test W CDMA Frame Structures ...
Page 667: ...643 18 Troubleshooting ...
Page 700: ...Index 676 Index ...