Bfo Frequency; Bfo Frequency: Keypad Entry; Bfo Frequency: Tuning Wheel Entry; Bfo Offset Switch - Watkins-Johnson Company WJ-8718A/MFP Instruction Supplement

INSTALLATION AND OPERATION
WJ-8718A/MFP
The tuned RF frequency display is decremented at the selected tuning resolution if
the tuning wheel is rotated counterclockwise. It is incremented, at the selected tuning
resolution, if the tuning wheel is rotated clockwise. Tuning past the end of the range (00.00000
to 29.9999 MHz), will cause the frequency to step to the other end of the band and continue
tuning in the same increasing or decreasing direction. The display will lock on the registered
frequency when the LOCK button is engaged and the tuning wheel will be ineffective. The
LOCK switch has no effect on keypad RF frequency entry.
2.4.4.4.3
FREQUENCY/MHz Display
RF frequency is displayed by a 7-digit, 7-segment LED readout. As the frequency
is entered, from MSD to LSD on the front panel keys, each digit is displayed in the LSB position
and is displaced to the left one space with each new numerical entry. This calculator-style
display reflects all numerical entries to the general purpose keypad, except BFO frequency,
until the terminator is entered.
2.4.4.5
2.4.4.5.1
BFO Freguency
BFO Frequency: Keypad Entry
To enter a BFO frequency via the keypad, the CWV and +/- BFO key must be
engaged. An entered number between -8.00 and +8.00 is terminated with kHz, and is displayed
by the BFO display.
2.4.4.5.2 BFO Frequency: Tuning Wheel Entry
The one-finger tuning wheel can be used to dial a BFO frequency if the BFO and
CWV switches are engaged. Selecting a tuning resolution via the TUNE switch block to the
right of the wheel disengages the LOCK switch and allows the tuning wheel to dial a BFO
frequency. The only effective tuning resolutions for BFO tuning are the 100 Hz rate (FAST) and
the 10 Hz rate (MED and SLOW). Rotating the wheel clockwise will increment the displayed
frequency from a negative offset, through zero, to the upper limit of the range. Rotating the
wheel counterclockwise will decrement the displayed frequency from a positive offset, through
zero, to the lower limit of the range.
2.4.4.5.3
+/-
BFO Offset Switch
The offset sign can be changed by the BFO +/- key. Pressing the key causes the
minus (-) sign to be alternately displayed and removed. Absence of the sign on the display
indicates positive offset.
2.4.4.5.4
BFO OFS/THRS LVL Display
The +/- BFO frequency is displayed on a 3-digit plus a minus sign (-), 7-segment
LED display. The BFO frequency can be entered locally via a keypad or tuning wheel. The BFO
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