DSP-599zx Audio Noise Reduction Filter
March 6, 1997
1-5
Features Common to All Modes
Random/Tone Noise Reduction
The noise reduction functions of the DSP-599zx operate by examining a
characteristic of signals and noise called correlation, and dynamically filter-
ing out the undesired signals and noise. The degree of correlation is relative.
Random noise such as white noise or static is uncorrelated. Speech is mod-
erately correlated. Repetitive or continuous noise such as a heterodyne is
highly correlated. The DSP-599zx measures correlation and filters out sig-
nals and noise that are outside its correlation thresholds. The amount of
noise reduction varies according to the correlation characteristics of the
noise. Typical noise reduction ranges from 5 dB to 20 dB for random noise
and up to 50 dB for heterodynes.
Adaptive Multi-tone and Manual Notch Filtering
(Tone noise reduction)
The DSP-599zx has both an automatic notch filter and a manually tuned fil-
ter. The automatic notch filter is an adaptive multi-tone filter that can re-
move multiple tones simultaneously. The automatic multi-tone filter
removes multiple heterodynes almost completely.
The
[Center Freq]
encoder on the front panel tunes the manual notch filter.
The manual notch filter is selectable and has a dual notch filter for data sig-
nals and a single notch filter for CW signals and heterodynes.
Dual Channel Operation
The DSP-599zx is a dual channel device with two sets of inputs and outputs.
The DSP circuit completely processes the selected channel, while signals on
the other channel pass through the DSP circuit without processing. Settings
for each channel are retained when switching between channels.
The two input channels allow you to connect either two separate radios or a
dual channel radio with two outputs to the DSP-599zx. You may configure
each channel to completely different operating modes. Selecting the oppo-
site channel returns the DSP-599zx to the previous settings on that channel.
This is very handy for two rig operations when setting one rig to monitor
CW and the other to monitor voice.
Function
6
Shift
5
AGC
3
Bypass
Setup
Test
Data
DSP-599zx
CW
Voice
Mode
Rcl/
Store
Spkr/
Chan
1
Random
4
Tone
2
599-006
High Pass
Center Freq
Time
Summary of Contents for DSP-599zx
Page 1: ...DSP 599zx Audio Noise Reduction Filter Operating Manual March 6 1997 TECHNOLOGY INC ...
Page 56: ...4 Voice Mode 4 8 March 6 1997 ...
Page 62: ...5 CW Mode 5 6 March 6 1997 ...
Page 92: ...8 Troubleshooting 8 4 March 6 1997 ...
Page 96: ...Appendix B Glossary A 4 March 6 1997 ...
Page 98: ...Appendix C Product Warranty A 6 March 6 1997 ...
Page 100: ...Appendix D Electromagnetic Interference A 8 March 6 1997 ...
Page 102: ...Appendix E Schematic Diagrams A 10 March 6 1997 ...
Page 103: ...DSP 599zx Audio Noise Reduction Filter March 6 1997 A 11 ...
Page 104: ...Appendix E Schematic Diagrams A 12 March 6 1997 ...
Page 105: ...DSP 599zx Audio Noise Reduction Filter March 6 1997 A 13 ...
Page 106: ...Appendix E Schematic Diagrams A 14 March 6 1997 ...
