Message-ID: <3A6DE60A.E0BD0990@tomcat.gsfc.nasa.gov> Date: Tue, 23 Jan 2001 20:14:02 +0000 From: Dr Thomas A Clark Organization: NASA/GSFC To: IGLOSMAIL CC: Robert Snow , Bob Lemoine , Chuck Kodak Subject: [IGLOSMAIL-186] GODZ Z-18 Receiver Firmware Update Sender: owner-iglosmail Precedence: bulk ****************************************************************************** IGLOS Electronic Mail 23 Jan 12:14:09 PST 2001 Message Number 186 ****************************************************************************** Author: Tom Clark, NASA Goddard Occasionally we have seen the Ashtech Z-18 RINEX data from our GODZ (Greenbelt) site become corrupted due to carrier phase observables overflowing from the specified F14.3 format to become F15.3. This problem happened again from about 15 thru 19 January. [GODZ is the Z-18 providing GLONASS+GPS data from the normal GODE IGS antenna using the same H-Maser clock] In the past, our quick fix for the Z-18 overflow problem had been to power cycle the receiver, which forced the cumulative carrier phase counter to zero itself, but we only did this when someone reported the fault. Last week we brought the ovserflow problem to Ashtech's attention and Bob Snow reported that there was a Z-18 receiver firmware upgrade from version 6.4 (which we had been using) to version 6.5 (which fixes the carrier phase overflow). Today (Jan.23) at ~noon EST (17:00 UTC) I installed the 6.5 firmware on GODZ, so the problem should not reoccur. The site was off the air from 16:38 to 17:20. If there are any other folks using Z-18s who have this problem, I have placed the two relevant Ashtech files on my anonymous ftp site: ftp://tac.gsfc.nasa.gov/pub/gps/ashtech/18p_0065.dat is the version 6.5 binary firmware image, and ftp://tac.gsfc.nasa.gov/pub/gps/ashtech/upld.zip contains the current Windows binary (.dat) uploader. Thanks to Maury Dube and Carrie Noll for spotting the GODZ RINEX problem and to Bob Snow and Bob Lemoine for responding quickly with the needed firmware. Regards, Tom