Xref: utzoo sci.electronics:21242 rec.radio.shortwave:7990 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!samsung!sol.ctr.columbia.edu!bronze!commgrp@silver.ucs.indiana.edu From: commgrp@silver.ucs.indiana.edu (BACS Data Communications Group) Newsgroups: sci.electronics,rec.radio.shortwave Subject: GPS error to be reinserted Message-ID: <1991Jun28.144253.8992@bronze.ucs.indiana.edu> Date: 28 Jun 91 14:42:53 GMT Sender: Organization: Indiana University Lines: 21 Last night I heard on WWV's GPS status report (15 minutes after the hour) that selective availability will be reinstated within the next few days. "Selective availability" (SA) is an encrypted intentional error introduced into the satellite navigation signals, ostensibly to keep enemies from using the system. However, SA was turned OFF last August at the beginning of the "Gulf Crisis." Apparently, there were not enough military-grade GPS receivers available so they pressed civilian units into service. There were rumors that SA would be left off permently due to political pressure from civilian and nonmilitary government GPS users. The WWV report is bad news, especially now that GPS receivers will soon reach the $1000 class. The Omega (VLF navigation system) status report on WWV (immediately following GPS) said that Omega may have 2-4 nautical-mile error during the solar eclipse. Can any propagation experts comment on that? -- Frank Reid W9MKV reid@ucs.indiana.edu