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Current Feature Articles   Jul 05 The Amateur Amateur: Please Answer the Following Question   Jul 04 Youth@HamRadio.Fun: Another Field Day in the Books   Jul 03 Surfin': ATVing Digitally and APRSing Successfully   Jul 01 ARRL In Action: What Have We Been Up to Lately?   Jul 01 It Seems to Us: Support HR 2160!   Jun 28 Dropping in on Field Day   Jun 27 Amateur Radio Quiz: Parting Words   Jun 26 Surfin': Finding Missing Sunspots   Jun 26 The Amateur Radio Crossword Puzzler   Jun 25 Doubling Up on Field Day ARRL Products: Circuit Design (More) Discrete-Signal Analysis and Design -- Now Shipping! -- A clear, step-by-step approach to practical uses of discrete-signal analysis and design, especially for communications and radio engineers. Introduction to Radio Frequency Design -- Basic RF concepts (with some related analog subjects) for the amateur or engineer. Digital Signal Processing Technology -- Essentials of the Communications Revolution. An understandable presentation and reference on DSP in contemporary communications technology. Experimental Methods in RF Design -- Now Shipping! -- Immerse yourself in the communications experience by building equipment that contributes to understanding basic concepts and circuits. ARRL's Hands-On Radio Experiments -- Over 60 basic electronics experiments from the pages of QST!

This week, visit a Web site that determines how well your signal gets from here to there.

The W5GFE Splat Page plots RF coverage maps and data for any radio station in North America.

Back in July 2005, Surfin' featured SPLAT!, an excellent Linux application from John Magliacane, KD2BD, that analyzes RF signal propagation, loss and terrain for the radio spectrum between 20 MHz-20 GHz. Using terrain data available from the US Geological Survey (USGS), SPLAT! analyzes point-to-point radio paths, as a well as coverage areas of repeaters and broadcast facilities. It generates coverage maps, charts and text reports that provide information on the location of obstructions due to terrain, as well as path-loss based on the Longley-Rice propagation model.

The coverage maps that SPLAT! creates are excellent. The program uses USGS's Digital Elevation Model (DEM) data to generate its maps and the results are very accurate, but to achieve those accurate results requires a large amount of data. Also, SPLAT! runs on Linux, which is not everyone's operating system of choice

To work around these features, Bill Walker, W5GFE, downloaded all the USGS files to what he calls "a rather hefty server" and added a Web interface that permits anyone to use SPLAT! via the Internet at the W5GFE Splat Page, thus relieving the user from running Linux and downloading large files

I gave W5GFE's SPLAT! online interface a workout and it performed flawlessly and quickly (about one minute to generate each plot), which is a feat considering the amount of data that the program must manipulate. Plot early to avoid the rush.

Until next time, keep on surfin'!

Editor's note: As a former amateur cartographer, Stan Horzepa, WA1LOU, loves maps and map-related applications. To communicate with Stan, send him e-mail or add comments to his blog. By the way, every installment of Surfin' is indexed here, so go look it up.