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[linrad] RE: Bamboozled by bandwidth
Thanks Lief I can see that I will have a lot of fun with a narrow
bandwidth first and no doubt will graduate from there.
Really appreciate all your work and responsiveness.
>> Just getting going here and have read all the QEX articles with great
>> interest. I am bewitched, bothered and bewildered over the question
>> of bandwidth requirements.
>> It would be useful to see a display of activity taking place in the
>> frequency spectrum of interest for example my operation is almost
>> exclusively in the low 25 kHz of the HF CW bands. When in QSO I only
>> need a 100 Hz or so and I note that Leif states that large
>> bandwidths are primarily required for noise reduction functions but
>> that increases the problems of dealing with large in-band signals.
>Absolutely. If you do not have local QRN at your QTH, then you should
>use an ordinary SSB transceiver and run Linrad without the second fft.
>> Given a high performance HF radio (mine is a Ten-tec Omni pro) with
>> 100 Hz Xtal filtering, linrad DSP and a 16 bit sound card what's to
>> be gained by more elaborate hardware measures that increase bandwidth
>> ? What am I missing ?
>You will miss what happens 10kHz away. The pattern on the waterfall
>display when something interesting occurs (pileup) is very characteristic.
>If you do not care - and if you do not need the blanker, use some 486
>computer from the junk yard and run Linrad only for baseband processing.
>(If you can figure out how to get Linux running on an old computer)
>Leif / SM5BSZ