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[linrad] Newbie's first impressions

For many months I have been meaning to get a Linrad system 
running at K1JT.  This weekend I had enough of the pieces 
together so that I took the plunge.  This note will share my 
initial experiences.  I hope it will encourage others to make the 
effort to install and use this remarkable piece of software.

1. First, you must acquire a suitable computer.  I decided to buy 
a new (but cheap) PC and dedicate it to running Linrad.  I bought 
a "Dimension 4600" from the Dell factory outlet.  This is the 
home of so-called "refurbished" machines, but believe me, you 
can't tell them from new.  Mine is a 2.7 GHz Pentium IV with 256 
MB RAM, a 40 GB, 7200 rpm disk, and on-board sound and video; I 
use a monitor I already had on hand.  Nothing fancy, but very 
capable; total price was $409, including shipping.

2. Next, I installed Linux.  I powered up the machine according 
to the Dell instructions, and verified that under Win XP Home 
Edition it behaved normally.  I changed the BIOS Setup option so 
that it can boot from a CD-ROM, inserted the Red Hat 9.0 Linux 
Installation Disk 1, and told the machine to reboot. I don't like 
"dual boot" machines much, so I wiped the Win XP and just 
installed Linux using the Red Hat "workstation" default options 
throughout.  Installation completed normally in about half an 
hour, and Linux was alive.

3. I downloaded and installed svgalib-1.4.3 and nasm, following 
instructions on the Linrad Home Page.  I changed the mouse 
definition in /etc/vga/libvga.config from "Microsoft" to "IMPS2".

4. I downloaded and installed the free "demo" version of the OSS 
sound drivers.

5. I installed Linrad 01.17.

6. I connected an audio cable from my FT-847 to the computer's 
"line in" sound connector.

7. I started Linrad and entered parameters shown in Leif's Linrad 
article in QEX, installment #4, in which he discusses the use of 
Linrad with an ordinary SSB receiver.

8. Going back to Linrad's main menu and pressing "A" to enter 
weak-signal CW mode, I heard Linrad come alive!  I tuned the 
FT-847 to one of the weak beacons on 222 MHz, and started playing 
with the Linux controls.  What can I say?  It just works!  It 
sounds good, the waterfall is terrific, the AFC works, you can 
play with filter bandwidths to your heart's content, etc.  The 
"point and click" tuning is remarkable.

I was immediately and VERY FAVORABLY impressed!

Total elapsed time, from unpacking my new (ah, make that 
"refurbished" Dell computer to listening to on-the-air signals 
with Linrad, was about 15 hours.  For 2 of those hours I was 
doing yard work, and for 8 hours I was asleep: this was a 
Saturday afternoon and Sunday morning project.

I have much to learn about Linrad.  I have a Delta 44 sound card, 
but have not yet installed it.  I need to pay for the permanent 
OSS license.  My wide-bandwidth, quadrature mixing, dual 
polarization front end presently exists only on paper.  But 
having had a taste of what Linrad can do, I am now eager to get 
going with the rest of the project!

One goal (which does not even require the wideband receiver) is 
to build a JT65 decoder onto the back end of Linrad.

I look forward to learning more of Linrad's capabilities from 
those on this reflector with much more experience.

			-- 73, Joe, K1JT