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[linrad] Linrad with single soundcard for processing audio from transceiver headphone output

Hello, All!

This is just a brief post on the above subject.

I don't as a rule run Linrad as an audioprocessor, and so I have been 
less than helpful when asked questions on this subject, I am afraid, 
because my memory of events of more than a year ago is not great, and 
because I was using Linrad versions less than 20 when I did this.

So today while trying to provide some realtime assistance I actually set 
up Linrad again on my Pentium Pro 200 to run as a post processor after 
my Ft1000.

I found the following:

1.  I just used the sound drivers that came with RHL 7.2.  I did not 
install OSS.

2.  I used a Creative Labs AWE 64 Gold soundcard.

3.  To mute (incompletely; there is still bleed thru if I turn up the 
FT1000 volume too much) the bleed thru of the original signal I had to 
use the Linux Audio Mixer (GMIX 3.0) to mute "Mix" and also mute 
"OGain".  I selected Line and checked "Rec" for the Line input.

4.  With this setup Linrad got adequate audio input and there was not 
objectionable bleedthru.

5.  Linrad gave #32 as my soundcard choice under option "U" (A/D and D/A 
 setup), and I made it RDWR, of course.

6.  On the last screen of Linrad parameters I set the Default Output 
mode to [3].  I don't know what this does or why this makes a 
difference, but it does.  I set it back to [1] and again I get no audio 
output from Linrad.

With these choices it Linrad does a good job of post processing.

However, I plan to go back to using Linrad on the 1.4 GHZ P4 with 90 KHz 
receive bandwidth :)  Linrad worked great for both EME contest this 
weekend and for the meteor shower.  But now I must change my call to 
'qrz' if I am to make more contacts.  50% of the stations that are Q5 
with Linrad cannot copy my 2 x 2 2mxp20 array with SWR 1.0:1, 7/8 inch 
hardline going to the array, and full legal power output.  Perhaps we 
need to make sure EVERYONE has a Linrad receiver.  Then we will be heard 
by the other stations as well as being able to hear them ;)  It was 
amusing to see on the Logger the statement "conditions are really good 
now" after I spent 90 minutes calling that station only to get QRZ, when 
I heard him Q5 and saw my own echos


Roger Rehr