Timewave DSP-599zx, Руководство по эксплуатации

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DSP-599zx Audio Noise Reduction Filter
March 6, 1997 5-1
5
CW Mode
Operation
The CW Mode digitally processes analog CW (Continuous Wave) signals
for Morse code reception. Independently selectable processing techniques
include noise reduction, tunable bandpass filtering and automatic gain con-
trol.
Bandpass Filters
A narrow band signal like CW and RTTY requires bandpass filters with
steep skirts and linear phase response. Linear phase response maximizes the
usable signaling rate for a given bandwidth and minimizes ringing often
heard on other types of extremely sharp filters. The filter skirts on the CW
filters are so steep that a signal literally falls off the edge of the passband as
you tune through a CW signal.
• Bandwidths range from 10 Hz to 600 Hz.
• Center frequencies from 200 to 2100 Hz.
The narrow filters are useful for trying to dig out extremely weak signals
from the noise and QRM. The wider filters allow easy tuning and listening
to multiple CW signals simultaneously.
In the CW Bandpass mode, the DSP-599zx tailors the audio input using tun-
able bandpass filtering, adaptive random noise reduction, and manual notch
filtering. These functions can operate simultaneously or independently. The
DSP-599zx also provides a marker tone at the center frequency of the select-
ed CW bandpass filter.
• Turn [Center Freq] to the desired bandpass center frequency indicated
on the lower left side of the display.
• Turn [Bandwidth] to the desired bandwidth noting the bandwidth in-
dicated displayed on the bottom right side of the display.
Function
6
Shift
5
AGC
3
Bypass
Data
DSP-599zx
CW Voice
Mode
1
Random
4
Tone
2
599-095
Setup Test
Rcl/ Store
Spkr/ Chan
High Pass
Center Freq
Timewave
Low Pass
Bandwidth
March 6, 1997