Chapter 7
477
Language Reference
FREF Frequency Reference
FREF Frequency Reference
Syntax
Figure 7-118
FREF Syntax
Description
The FREF command specifies the frequency reference source. Select
either the internal frequency reference (INT) or supply your own
external reference (EXT). An external reference must be 10 MHz (
±
100
Hz) at a minimum amplitude of 0 dBm. Connect the external reference
to J9 (10 MHz REF IN/OUT) on the rear panel. When the external
mode is selected, an
"X"
appears on the left edge of the display.
Preset State
Internal
Query Response
Figure 7-119
FREF Query Response
Example
10
INPUT "WHAT IS THE FREQUENCY REFERENCE SOURCE (INT OR
EXT)",Src$
20
OUTPUT 718;"FREF ";Src$;";"
30
PRINT "SOURCE SELECTED IS",Src$
40
END
Summary of Contents for 8560E
Page 21: ...21 1 Quick Start Guide ...
Page 48: ...48 Chapter1 Quick Start Guide Manuals Available Separately ...
Page 49: ...49 2 Making Measurements ...
Page 164: ...164 Chapter2 Making Measurements Example 13 Making Pulsed RF Measurements ...
Page 165: ...165 3 Softkey Menus ...
Page 182: ...182 Chapter3 Softkey Menus Menu Trees ...
Page 183: ...183 4 Key Function Descriptions ...
Page 228: ...228 Chapter4 Key Function Descriptions Key Descriptions Figure 4 3 CRT Alignment Pattern ...
Page 289: ...289 5 Programming ...
Page 323: ...Chapter 5 323 Programming Math Functions Figure 5 10 Display Units ...
Page 339: ...339 6 Programming Command Cross Reference ...
Page 369: ...369 7 Language Reference ...
Page 654: ...654 Chapter7 Language Reference VTL Video Trigger Level ...
Page 655: ...655 8 Options and Accessories ...
Page 665: ...665 9 If You Have a Problem ...
Page 674: ...674 Chapter9 If You Have a Problem Power Requirements Figure 9 2 AC Power Cables Available ...