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Current Feature Articles   Nov 21 Surfin': Revisiting Radio Monitoring Memories   Nov 17 The Amateur Amateur: Radiomobile   Nov 17 Handy Reference   Nov 14 Surfin': Tying Ham Radio Together with Twine   Nov 07 Surfin': How We Got Here   Nov 03 Amateur Radio Quiz: A Spare Hour's Entertainment   Nov 03 ARRL In Action: What Have We Been Up To Lately?   Nov 01 It Seems to Us: The Next Time Could Be Different   Oct 31 The Canaries in the Mine   Oct 31 Surfin': I Phone, Therefore I Ham ARRL Products: Technical, Electronics, and Communications Reference (More) Basic Antennas -- Now Shipping! -- An introduction to antennas--basic concepts, practical designs, and easy-to-build antennas! ARRL's Low Power Communication with 40-meter CW Cub Transceiver Kit -- Now Shipping! -- Build and operate low-power radio gear--the QRP way! 3rd Edition. Includes the 40-meter CW Cub Transceiver Kit. Power Supply Handbook -- Gain the knowledge and confidence you need to build and use power supplies. A must have for your bookshelf! The ARRL Antenna Book -- The ultimate reference for Amateur Radio antennas, transmission lines and propagation. Fully-searchable CD-ROM included. 21st edition. The ARRL Handbook (2008 softcover edition) -- Now Shipping! -- THE standard in applied electronics and communications.

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.