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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