HP 3314A - Page 68

MODE (cant)
Fin X N
The 331 4A output frequency will be N times the reference frequency. The
reference and 3314A frequencies are limited from 50Hz to 19 .99MHz.
Lock acquisition by the 3314A is completely automatic unless Frequency Range
Hold is asserted.
Whenever the reference frequency drifts more than 10%, the
3314A auto-acquisition re-establishes phase lock. When the Fin X N light is
flashing,
the 3314A is acquiring phase lock. The acquisition procedure used by
the 3314A is:
-measure
the reference frequency.
-display E20 and stop acquisition If the reference frequency is unstable.
-set
the 3314A frequency to N times the reference frequency.
-t urn the phase locked loop ON and acquire lock.
The 3314A will not proceed past the measurement step if the reference frequency
is chang ing (see Pre-Tuning the 3314A's Oscillator). The 3314A may be able to
acquire phase lock to a changing reference if you try the following:
-while in FREE RUN, set the 3314A frequency to N times the reference
frequency.
-set Frequency Range Hold ON.
-change
the mode to Fin X N.
At this time, there are 2 primary concerns which will preclude acquiring phase
lock.
1. The 3314A's output frequency is limited to + 10% and -50% of the disp layed
value.
Note that the Fin X N light will flash when the frequency exceeds
± 10%.
2. The reference frequency change must be within the bandwidth of the 3 314A' s
phase locked loop.
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