[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Linrad with single soundcard for processing audio from transceiverheadphone 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