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“Scanning RF Seismograph” Monitors HF Propagation in Real Time

06/17/2016

A “Scanning RF Seismograph,” a real-time HF propagation-monitoring tool developed by the MDSR Team and Alex Schwarz, VE7DXW, of the North Shore Amateur Radio Club (NSARC), has been established in Western Canada. The site is in Lynn Valley (CN89li), North Vancouver, British Columbia, at 500 feet ASL.

A Yaesu FT-950 transceiver connected to an omnidirectional multiband antenna monitors JT-65 frequencies on six HF bands (for 8 seconds each, repeating the scan every 52 seconds). Recorders monitor the background noise of the band and display the result in six color-differentiated (one color per band), long-duration graphs displaying a total 6 hours of scans. When signals are present on a band, its graph trace starts to resemble a series of vertical bars.

Small, irregular jiggling of the graph traces is caused by changes in noise level and by the reflection of noise off the D Layer of the ionosphere, Schwarz explained.

The web link is updated every 10 minutes.

For more information, contact Alex Schwarz, VE7DXW. 



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