DRS WJ-8611, Инструкция по установке, эксплуатации и обслуживанию

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WJ-8611 DIGITAL VHF/UHF RECEIVER
LOCAL OPERATION 3-7
When the SQUELCH key is pressed, the LED on the key illuminates, and
one of the digits in the SQUELCH field of the parameter display flashes,
indicating that the squelch update mode is under active control by the
EDIT knob. With each press of the SQUELCH key the display changes
from a flashing: 1 dB digit, 10 dB digit, OFF, or ON. When in this mode,
the receiver’s squelch setting may be set by rotation of the EDIT knob, or
by direct entry at the numeric keypad. Rotation of the EDIT knob changes
the squelch level in 1 dB or 10 dB increments, based on the digit that is
flashing in the Squelch (SQL) display. The control range is from -30 to
-130 dBm. If the absolute value is increased beyond -130, the squelch is
set to the OFF position. If the absolute value is decreased beyond -30, the
squelch is set to the ON position.
Direct entry is performed by entering a value ranging from 30 to 130 and
terminating the entry with the SQUELCH key. This value represents
squelch levels of from -30 to -130 dBm. Entering a value of 29 or 131 sets
the squelch to ON or OFF, respectively. When squelch is set to ON, the
squelch is active at all times. No signal will be recognized, and the audio
outputs are disabled, regardless of its level. When squelch is set to OFF,
The receiver circuits are always active, and the audio outputs are active,
even when no signal is present.
AUTOMATIC FREQUENCY CONTROL
KEY
(AFC)
The AFC control key sets the automatic frequency control function on or
off. This function is selectable in the AM and FM detection modes and
only when the active IF bandwidth is set to 3.2 kHz or greater. When AFC
is active, the LED on the AFC key is lit. Each press of the key toggles
AFC ON (LED lit) or OFF (LED extinguished). When active, the
automatic frequency control function attempts to fine tune a signal that
exceeds the squelch threshold into the center of its IF bandwidth for best
reception. This function is most useful when the receiver is performing an
F1-F2 scan. It attempts to center tune an acquired signal before reporting
the signal contact to the receiver front panel.
NOISE BLANKER CONTROL KEY
(BLANKER)
The BLANKER control key is used to activate or disable the noise
blanking function. This function, when active, reduces the effects of noise
bursts at the audio outputs by blanking the output momentarily when the
noise bursts occur. The BLANKER function may be activated in the AM,
LSB, and USB detection modes, and it provides a 1 to 10 msec blanking
range. The BLANKER key activates (LED on) and disables (LED off) the
blanking function, toggling between on and off with each key press. Weak
signals near the ambient noise level, prevent the BLANKER from
distinguishing noise and the actual signal. This condition could cause
unreliable operation. A signal-to noise ratio of at least 12 dB ensures
reliable BLANKER operation. The actual setting of the blanker value is
performed in the Configuration Menu, as described in
paragraph 3.2.9.
Courtesy of http://BlackRadios.terryo.org