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Re: [linrad] RE: Newbie's first impressions

Leif --

> For narrowband you do not need OSS, the builtin driver
> of RedHat 9 is usually working fine. Just run sndconfig.
> If you are lucky the soundcard you have is supported:-)

Yes, I understand this.  I want OSS only because I will soon be 
installing and using the Delta 44.

> That means you would have to add a second screen for the JT65
> user interface. Linrad uses svgalib. You can move the windows to 
> make room for a JT65 user interface, but I do not think you can
> write on the free part of the screen from another program.
> It would be trivial to send data to another program on a different
> terminal on the same computer or on another computer (I think)

For initial tests I would expect to be logged into the linux 
machine from another computer.  Because of the way Linrad "takes 
over" full use of the keyboard and monitor, such external access 
to the linux machine would seem very helpful to have, anyway.

At some later time, it might be desirable to have tighter 
coupling between the programs.  For example, WSJT/JT65 could send 
decoded text back to Linrad for display.

> There are several formats within Linrad. The audio output is not the
> one to use. Not that there is anything wrong with it, but it
> is computed by fractional resampling from a typically much lower 
> sampling rate, it is then frequency shifted by the BFO frequency.
> I would suggest the complex baseband signal I and Q. You could take
> it from the output of the baseband filter, but since JT65 has its own
> filters you might equally well take it from the input side where the
> bandwidth is what you select with the "first mixer bandwidth reduction"

Yes.  I did not mean literally that the audio output data would 
go to the JT65 decoder.

> Linrad is designed to process many channels in parallel so you can
> have several JT65 detectors running simultaneously. This is a feature
> that is only halfway implemented because it is meaningless with 
> loudspeaker output. It is intended for use with the CW decoding
> routines AND with all other kinds of digital decoding that lead to
> ascii on the screen. Right click for loudspeaker and ascii, left 
> click for ascii only on a different frequency:-)

It sounds great, but I think I'll try one detector first. :-)

> I think this section could be the difficult one. 
> Visual Basic + svgalib = ????   (maybe #%$&)

Sorry, I was not clear here.  The Windows version of WSJT uses 
Visual Basic for its user interface.  I would certainly not use 
anything like that language under linux.

		-- 73, Joe, K1JT