HP 8920A - AM Depth; Audio in lo; Current; DC Current

103
Chapter 5, AF Analyzer Screen
Block Diagram
AM Depth
This field displays the percent depth of modulation of the AM signal. The field is
only visible when the
AF ANL In field is set to AM MOD or AM DEMOD
Audio In Lo
This field sets the AUDIO IN LO connector’s state.
• Gnd causes the center pin of the connector to be connected directly to chassis ground.
• Float isolates the center pin of the connector from ground, providing a floating input
to the AF Analyzer.
• 600 To Hi establishes a 600-ohm impedance between the center pins of the AUDIO
IN LO and AUDIO IN HI connectors. Also, the Ext Load R field is removed, since
the load is now fixed to 600 ohms.
Current
The Current field is found by selecting the SINAD field on the Test Set display
of the AF ANALYZER screen. This field only displays the DC current measured
at the DC input port on the back of the Test Set. Any offset can be removed by
selecting
Zero from the DC Current field.
DC Current
DC current measurement zero removes any measurement offset present before
making a dc-current measurement
1
. The measurement is zeroed by selecting
Zero, and pressing the ENTER key or the Cursor Control knob.
1. HP 8920A requires option 103.
NOTE: The current source must be disconnected before zeroing for accurate operation.
See Also
"DC CURRENT MEASUREMENT" on page 565
"SINAD, Distortion, SNR, AF Frequency, DC Level, DC Current" on page 60
Chapter 24, "Connector, Key, and Knob Descriptions"