BIRD 7001A900-2, Руководство по эксплуатации

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User Interface Description
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
Multi-Level Pulse - Rising edge of sync pulse is used to start measurement period, up to four pulse
states, for each fundamental, may be measured during the measurement period, receiver tracks
frequency during each individual state. States are defined in the
Multi-Level Mode
area below.
Tracking —
Selection for fixed frequency or tracking frequency mode.

Fixed Frequency Mode - The frequency tracker will not run and the measurement will be fixed to a
single frequency. The BDS will return measurement values only at this exact frequency.

Tracking Frequency Mod e - The frequency tracker will sweep through frequencies within the range
of the selected fundamental's bandwidth to lock onto the test signal's exact frequency.
VI —
Allows the user to specify tracking of the measurement signal using the voltage or current.
If auto tracking is selected, the BDS will perform its signal tracking based on the larger of the
two.
State 1 - 4 Frequency —
Allows the selection of the frequency for each state.

Fixed Frequency Mode, this specifies the frequency where the measurement will occur for each
state.

Tracking Frequency Mode, this specifies which frequency the frequency tracker will begin its search
from.
Note:
Specifying a frequency close to the actual frequency of the signal will speed up lock time.
Pulse Mode Sync Delay — Allows the entry of time delay, following the sync pulse, before
the receiver begins measurement.
Multi-Level Mode —
Entries are required when Multi-Level Pulse is selected in the fundamental’s
Tracking
Settings
.
Multi-Level Mode options:

Number of States - This option is used to define the number of states (pulse levels) used during
each fundamental measurement period.

Delay - A time delay, from the rising edge of the sync pulse, must be entered for each state, this
provides the receiver the information required to begin measurement of each state.

Duration - The length of time (pulse width) of each state must be defined, for each state. The
duration value provides the information the receiver needs to measure the full width of each state.

Number of Frames - If a state duration is less than approximately 25 µsec, entering the number of
frames (pulse periods) for a state, allows the receiver to “focus” on tracking a single state for the
selected number of frames to “lock” onto the frequency.

Pulse Period - The length of time (period) of the entire frame of multi-level states. This should
match the period of the external sync pulse.