Subject: [IGLOSMAIL-269] Ashtech Z-18 Firmware
From: Dr Tom Clark <[email-masked]>
To: IGLOS <[email-masked]>
Cc: Robert Snow <[email-masked]>
Date: Mon, 30 Apr 2001 15:46:12 +0000

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IGLOS Electronic Mail      30 Apr 08:46:23 PDT 2001   Message Number 269
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Author: Tom Clark

Rob Sherwood <[email-masked]> and I have had a discussion about Z-18
Firmware and the overflow of Carrier Phase when GBSS is used to make the
RINEX files. I gave Rob the fix that Z-18 firmware release 6.5 fixed the
problem here at GODZ and Rob reported that most of the European Z-18s
are still running 6.4 (which has the overflow problem). 

The problem shows up when the Hatanaka compressor fails after a few
weeks of operation when F14.x format numbers spill over to a length of
15 characters. A temporary fix is to cycle the receiver power (resetting
the cumulative phase counter), but the real fix seems to be to upload
the new firmware.

Since it appears that some Z-18 owners have not learned about the 6.4 =>
6.5 upgrade, I have made copies of the software available at URL

   ftp://aleph.gsfc.nasa.gov/pub/z18/

In that directory you will find 2 files -- 18p_0065.dat is the binary
receiver image and upld.zip contains the Windoze-based binary file
uploader.

Thanks to Robert Snow and Bob Lemoine at Ashtech for providing this
firmware upgrade. Hope it helps you all.

Regards, Tom