January 4, 2005
Bruce Tanner, W8ISC and Dave Metzger, K8GVK
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INTRODUCTION to SURVEY RESULTS
The information available on these pages constitute baseline readings of short wave reception on January 4, 2005 at several locations on the East side of the community of Grand Ledge, Michigan. The time period was from about 1800 to 2100 UTC. The readings are in *.mpg file format. These are digital recordings of the front data panel of an ICOM IC-756 Pro II transceiver used for the data collection. These readings were taken while stationary at several locations around the Grand Ledge community. The antenna used was a 45 foot wire antenna, vertically polarized, attached to a random wire electronic tuner. The samples were taken with the front end attenuation set for 12 db down and the Spectrum Scope was set for 30-20 db attenuation during most of the monitoring periods. The Spectrumscope scale was set for 100 KHz each side of the center frequency being monitored. At each location we monitored frequency sets consisting of WWV frequencies 5, 10, 15 and 20 MHz; CHU Canada time signal on 7335 KHz; the Midcars Net frequency at 7258 KHz as well as a scan of portions of the 40 and 20 meter Amateur Radio bands, and a scan of the 17 MHz International short wave broadcast band. Propagation was providing no WWV signal at 5 MHz so those data files were left off the site in the interest of lowering the storage space a little.
The samples were obtained while stationary in parking lots at significant locations in Grand Ledge, Michigan where reception of radio signals in the High Frequency bands for various reasons might be important for local and international communications. The first location was at the Lutheran Church on Clinton Highway, the second was in the parking area outside the Grand Ledge Fire and EMS station, the third was taken in a parking area adjacent to the Air National Guard installation on the North end of the community.
As you might expect from a baseline study the analysis of this data suggests that there was little noise factor and fairly good propagation of signals on this wintry, early afternoon. The average noise floor tended to be from 1 or 2 S units to perhaps 5 S units but in no case did the noise significantly interfere with the reception of signals we attempted to access. The deployment of BPL equipment was not present during this monitoring session so we were unable to focus on particular locations in proximity to known BPL injectors and related hardware. In each location we noted that we were within 50 to 100 meters of power line installations. The first location might be considered typical for a suburban, residential area; the second was in a more downtown, somewhat industrial and commercial area and the third location was typically rural in nature with the exception that it was next to a small air field use by the State Air National Guard.
As noted this monitoring session was initiated to obtain baseline data to assess pre installation and deployment of the Grand Ledge BPL services which are scheduled for deployment in June 2005. An additional survey and monitoring session for comparison data will be conducted subsequent to deployment using this same format for received frequencies and target locations. Additional locations and receive formats may be added to accommodate then known locations of BPL hardware.