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Date: Fri, 22 Feb 2002 15:05:16 -0800
From: "Angelyn W. Moore" 
To: igsmail@igscb.jpl.nasa.gov
Subject: [IGSMAIL-3758]: TurboRogue L2 tracking
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IGS Electronic Mail      22 Feb 15:05:18 PST 2002      Message Number 3758
******************************************************************************

Author: Angelyn Moore

Dear Colleagues,

Recalling IGSMail #2071, TurboRogue receivers have been
known to experience significant degradation of L2 tracking
during times of high ionosphere.  
(http://igscb.jpl.nasa.gov/mail/igsmail/1998/msg00298.html)
This effect continues to be seen today in all TurboRogue 
stations not operating in a one-second sampling mode, and 
negatively impacts the IGS network effectiveness. 

A firmware upgrade for such receivers appears to 
correct this difficulty.  Several IGS stations have
utilized this firmware version and the L2 tracking
is seen to be restored at the time of the firmware 
installation.

I've prepared two graphs to demonstrate.
http://igscb.jpl.nasa.gov/images/aoa1_p2c1.gif shows
that tracking when P2-C1 exceeds 12m was restored
at the time of the upgrade.  (Although not too obvious
on this scale, the quantization effect for 8m