Timewave DSP-59+, Руководство по эксплуатации

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Wideband Data Operating Hint
The DSP-59+ can simulate almost any filter necessary for wideband signals such as wide shift
RTTY. If you know the upper and lower audio frequency limits of the signal you are using,
simply set the Highpass and Lowpass filters to pass those frequencies. The linear phase response
and steep skirts of DSP-59+ will help reject QRM and improve S/N ratio. If you don't know the
frequency limits, tune in a strong signal with the Highpass and Lowpass filters set to 300 Hz.
and 2.7 kHz., and then tighten up the filters until the copy from the signal begins to degrade.
Then back off the filters one step or until the copy is acceptable. Note these highpass and
lowpass settings and use them when you operate that mode. You will have optimum QRM
rejection and the best signal-to-noise ratio.
5.2 CW Bandpass
In the CW Bandpass mode, the DSP-59+ tailors the audio input using one of 195 bandpass
filters, and will also adaptively reduce random noise. These two functions can operate
simultaneously or independently. The DSP-59+ also provides a marker tone at the center
frequency of the selected CW bandpass filter.
To activate the bandpass filter mode, depress the red BP push-button. Turn the Center
Frequency control to the desired frequency indicated by the red numbers around the Center
Frequency control. Turn the Bandwidth control to the desired bandwidth indicated by the red
numbers around the Bandwidth control. One bandpass filter is always active in BP mode.
To activate random noise reduction, depress the push-button marked "NRr". Random noise
reduction and bandpass filtering can operate simultaneously or independently. Just depress the
desired combinations of push-buttons.
CW Operating Hint
The extremely narrow linear phase filters in the DSP-59+ will allow you to copy very weak and
closely spaced CW signals. Use 25, 50, 75, and 100 Hz. bandwidths, but tune very slowly.
Since many radios are difficult to tune slowly, use the bandpass center frequency control to help
pick out the weak and closely spaced signals. If you are not interested in working very weak
signals, tune with the bandwidth set at 150 to 600 Hz. and decrease it if you need to eliminate
QRM. Use the 25 Hz. bandwidth if you are trying to copy a very slow CW signal (10 words per
minute or less). EME (Moonbounce) is a typical application for the 25 Hz. filter. Random noise
reduction (NRr) is especially helpful when listening to CW in the 400-600 Hz. bandwidth.
Use the NRr and AGC combination to boost the level of very weak CW signals when your
receiver is at maximum gain. Some CW signals seem to magically pop out of the noise.
CW Marker Tone
To activate the marker tone for CW, depress the Tone (or Marker on some units) push-button.
The DSP-59+ generates an audio tone at the center frequency of the selected bandpass filter for
all filters from 400 Hz. through 1000 Hz. and for the optional Collins CW filters.