HP 8921A Programmer's Manual page 460

Chapter 8, Programming The Call Processing Subsystem
Programming The CALL CONTROL Screen
[] Active
AF Freq
460
When lit, the
Active
Set is turned on.
If this annunciator is lit, the Base Station is transmitting system parameter
overhead messages on the assigned control channel. If the annunciator is not lit
the base station is not active (note that the Test Set may still be outputting a
modulated RF carrier but the Test Set's firmware is not active and no
communication can occur between a mobile station and the Test Set).
The annunciator is not programmable.
Active
The state of the
Active
Register Group Condition Register bit 0. See "Status Reporting" in the User's
Guide for further information.
The field is displayed only when the
AF Freq
This field displays the audio frequency of the demodulated FM signal being
transmitted by the mobile station. Four dashes (----) indicate that no audio
frequency is present to measure. A numeric value would only be displayed when
the Test Set's
Connected
Refer to the
Display field description, on page 465
read measurement results from this field.
annunciator indicates that the control channel of the Test
annunciator is reflected in the Call Processing Status
annunciator is lit.
field is set to
Display
, for information on how to
.
Meas