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

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WJ-8611 DIGITAL VHF/UHF RECEIVER
3-20 LOCAL OPERATION
ISB
The ISB selection provides simultaneous demodulation of the upper and
lower sidebands of single sideband type signals. In this detection mode,
the IF bandwidth is automatically set to 6.4 kHz, and cannot be changed.
The Automatic Frequency Control (AFC) feature is not available for
selection. The Line B audio output, and the Left PHONES output contain
audio extracted from the lower sideband of the signal. The Line A audio
output and the Right PHONES output contain the audio extracted from the
upper sideband.
3.3.3 DETECTION MODE MATCH
Unless programmed otherwise, each time that the detection mode is
changed, the IF bandwidth and the mode of gain control (AGC FAST,
AGC SLOW, or MANUAL) remains at its previous selection and must be
set to accommodate the signal characteristics of the signal type. (USB,
LSB, and ISB IF bandwidths are set automatically.) The Detection Mode
Match feature, available in the Configuration Menu (
paragraph 3.2.9 ),
causes the selected IF bandwidth and the gain control mode to be
remembered when the detection mode is changed. The next time that the
detection mode is activated, IF bandwidth and gain control mode is
restored to the last selections for that mode. With the Detection Mode
Match set to ON, each of the detection mode selections will retain the last
selected IF bandwidth and gain control mode setting. In the manual gain
mode, the detection match feature does not store the actual attenuation
setting.
3.3.4 IF BANDWIDTH SELECTION
There are a total of seventeen IF bandwidth selections programmed into
the receiver, ranging from 200 Hz to 200 kHz. The receiver can be
configured to create a selection list where anywhere from 2 to all 17
bandwidths are available for selection. (The 3.2 kHz and 6.4 kHz IF
Bandwidths cannot be excluded from the available list.) The receiver
defaults with all 17 IF bandwidths included in the selection list. The IF
BW key is used to select the active IF Bandwidth from the selection list.
When the key is pressed, the LED on the key lights, and the currently
active IF Bandwidth flashes in the BW(kHz) field of the parameter display.
Each press of the IF BW key increments through the list of available
bandwidths, increasing the bandwidth size with each press. When the
widest available bandwidth is reached, the display wraps around to the
beginning of the list. When in the IF BW selection mode, the EDIT knob
may also be used for IF bandwidth selection. Any bandwidth included in
the selection list may be activated when the receiver is in the AM, FM, or
CW detection mode. If the receiver is in the USB or LSB detection mode,
the IF BW key is disabled, and the 3.2 kHz bandwidth is activated. If the
receiver is in the ISB detection mode, the IF BW key is disabled and the
6.4 kHz bandwidth is activated.
IF BANDWIDTH
Courtesy of http://BlackRadios.terryo.org