Re: [linrad] Linrad on the air

["Rein A. Smit" <rein0zn@xxxxxxxxxxxxxxxxx]

Hi Joe,

Do you allow me to add these comments ( "Linrad on the air"  ) to your Linrad_dat page?

73 Rein W6/PA0ZN

Joe Taylor wrote:
> 
> Much of the traffic of this reflector is involved with technical issues
> concerning Linrad setup and use, and with the associated hardware.  It
> occurs to me that reports of actual on-the-air use of Linrad may also be
> of interest.  After all, for most of us, that is the ultimate purpose of
> the effort we put into any aspect of our stations, be it antenna,
> transmitter, receiver, or various other accessories and software.
> 
> I have had Linrad running for just three weeks, and my present setup is
> simple.  I use only one polarization channel and process the audio
> output from my TS2000 transceiver.  In its widest SSB filter setting,
> the TS2000 provides a bandwidth of about 5 kHz.  Of course, Linrad
> handles the computational burden very easily: the CPU load on my 2.7 GHz
> Pentium 4 is usually between 1% and 10%, depending on the exact
> parameters selected.
> 
> Although my receiving system is minimal for Linrad and I have much to
> learn in using the program, I have now made several 144 MHz EME CW QSOs
> using it.  My station is really a "tropo" station, not an EME station.
> I run about 700 W to 4 x 9el yagis aimed at the horizon, with no
> elevation control.
> 
> I can already say that Linrad provides the following advantages:
> 
> 1. Excellent waterfall display for locating the desired signal and
> discriminating against birdies;
> 
> 2. Very easy single-mouse-click tuning;
> 
> 3. Smoothly and continuously adjustable filter bandwidths and shapes;
> 
> 4. Automatic frequency control that keeps a CW signal centered in the
> bandpass, compensating for changing Doppler and oscillator drifts.
> 
> I have not yet gained much experience with the noise-blanking
> capabilities of Linrad, so I cannot comment usefully on this feature.  I
> believe I will need larger bandwidth before its main benefits can be
> realized.  Dual polarization is also very much on my "To Do" list.  I
> have compiled and tested the JT65 decoder under Linux, but have not yet
> tried sending Linrad output into it.
> 
> In the meantime, I am writing to encourage others to get on the air with
> this extremely capable software radio "back end".  And when you do,
> please share your Linrad operating experiences with the rest of us!
> 
>                         -- 73, Joe, K1JT


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