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Re: [linrad] Fw: Linrad-01.03

I am now using Delta 44 for input and SB Live for output. I have tried
various output sampling rates from 8000 to 11025 and tried dragging the
(upside down U's) and the best bandwidth I can get on the output audio is
900 to 1000 hz. I am trying to get 1700 to 2000 hz. Thanks very much for the
information you have sent me. 73, Dick.

----- Original Message ----- 
From: "Leif Åsbrink" <leif.asbrink@xxxxxxxxxxxxxxxx>
To: <linrad@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Monday, August 25, 2003 23:49
Subject: RE: [linrad] Fw: Linrad-01.03

> Hi All,
> > First, I am somewhat non-plussed at the trouble you had with RHL.
> >  Multiple versions
> > of Linrad have worked with well here with versions of RHL from
> > 6.0 thru 8.0,
> > including 7.x.  And I have used the Delta44 [along with various
> > soundblaster cards
> > for the output] with each of these versions with good results.
> It is not quite as easy...........
> I spent a day trying to get Linrad running on a PIV machine
> with a modern motherboard with integrated sound, video,
> modem, ......
> The machine had RedHat 7.3 already installed and I tried
> all possible combinations of everything but it was impossible
> to get the Delta44 to work. The system crashed (reboot) every time
> Linrad tried to open dsp2 in RDWR mode. Selecting dsp0 fixed did not
> help, the system would just crasch at a later stage.
> After too much time I decided there is no combineation of anything
> selectable I did not try including several different oss versions
> so I replaced RedHat 7.3 with Mandrake 8.1 which has always worked
> perfectly on my PIII. No change whatsoever.
> The next day I tried to boot the computer from another hard disk.
> Suddenly everything worked beautifully!!!!!
> The reason turned out to be that RedHat 8.0 is ok for this modern
> motherboard while the older distributions are not.
> I do not claim to understand anything of this, but I would
> formulate it like this: "there is some incompatibility between
> the OSS driver for Delta44 and elderly Linux kernels when a
> system is run on modern motherboards"
> Installing Linrad is not always trivial. I am sorry about that.
> If you are lucky it IS easy:) Chances are good you will find that
> everything works fine at the first attempt. If you run into problems,
> there is most probably a way out - but it may be hard to finbd it.....
> >.
> >.
> >.
> > You have full graphical control over the filter bandwidth with
> > Linrad.  You go to the
> > baseband window and just pull the filter width to be what you
> > want with the mouse.
> But you are limited by the first mixer bandwidth reduction ratio.
> It can be set by a fatcor whichnis a power of two.
> If you ask for N=4 (the default value), the baseband is sampled
> at 96/16 = 6kHz. When a 6kHz section is picked from the frequency
> domain, a window function is used - the flat bandwidth is then
> 3kHz which would be the maximum bandwidth you can select in this
> case. There is another limitation as well. If you set the output
> sampling speed to 6kHz you will not be permitted to set the bandwidth
> above 3kHz.
> 73
> Leif / SM5BSZ