40 Chapter 2
E4438C Vector Signal Generator Overview
Rear Panel Overview
9. Q-bar OUT Connector (Option 001/601 or 002/602)
This female BNC connector is used in conjunction with the Q OUT connector to provide a balanced
baseband stimulus. Balanced signals are signals present in two separate conductors that are symmetrical
relative to ground, and are opposite in polarity (180 degrees out of phase). The nominal output impedance of
this connector is 50Ω, DC-coupled. The damage levels are > +2 V and < −2 V. The DC origin offset is
typically < 10 mV. The output signal levels into a 50Ω load are as follows:
• 0.5 V
pk
, typical, corresponds to one unit length of the I/Q vector.
• 0.69 V
pk
(2.84 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.5.
• 0.71 V
pk
(3.08 dB), typical, maximum crest factor for peaks for π/4 DQPSK with alpha = 0.35.
• Typically 1 V
p-p
maximum.
If you configure your signal generator with Option 1EM, this output is relocated from a BNC to an SMB
connector.
10. EVENT 1 Connector (Option 001/601 or 002/602)
This female BNC connector outputs a pulse that can be used to trigger the start of a data pattern, frame, or
timeslot. It is adjustable to within plus or minus one timeslot with one bit of resolution. With Option 401
installed, an even second output is generated. A marker is output every two seconds indicating the beginning
of each short code sequence for use in synchronizing CDMA analysis instruments.
There is a marker on/off condition associated with each waveform point. The marker 1 level is +3.3 V
CMOS high when positive polarity is selected; –3.3 V CMOS low when negative polarity is selected. The
output on the EVENT 1 connector occurs whenever Marker 1 is turned on in the waveform. (Markers are
automatically turned on whenever you set them in a waveform segment. When you combine waveform
segments that contain Marker 1 into a sequence, the markers are automatically turned off until you toggle
them on in either the Edit Selected Waveform Sequence menu or in the Build New Waveform Sequence
menu.)
The damage levels for the Event 1 connector are > +8 V and < −4 V. On signal generators with Option 1EM,
this output is changed from a BNC to an SMB connector. With Option 401 you can select from several
different output signals for this connector.
11. EVENT 2 Connector (Option 001/601 or 002/602)
This female BNC connector outputs a data enable signal for gating external equipment. The output is
applicable when the external data is clocked into internally generated timeslots. Data is enabled when the
signal is low. With Option 401 installed, a marker is output on the EVENT 2 connector every
26.67 milliseconds, corresponding to the start of each short code.
There is a marker on/off condition associated with each waveform point. The marker 2 level is +3.3 V
CMOS high when positive polarity is selected; –3.3 V CMOS low when negative polarity is selected. The
To Next Page
Loading...
Need help?
General
