[teqc] odd teqc bug found

[Lou Estey]

Re: email to teqc list 23 Oct 2008
http://ls.unavco.org/pipermail/teqc/2008/000745.html

This week, after sorting through some qc multipath issues discovered
for a handful of sites archived at CDDIS, I determined that
condition (1) in the above email is _not_ required for the
incorrect qc to occur -- just conditions (2) and (3):

2) the "# / TYPES OF OBSERV" header line precedes the "REC # / TYPE / VERS"
header line, and

3) the receiver type is identified in the "REC # / TYPE / VERS" header line
as being from an Ashtech receiver (i.e. the type field starts with "ASHTECH")

If both of these conditions occur when using a teqc version between
19 Mar 2008 and before 22 Oct 2008, the resulting qc is potentially
wrong and should not be used.

There are two solutions:

a) Use a version of teqc that is 22 Oct 2008 or later. The last
full build release of 23 Mar 2009 accomplishes this goal:
http://facility.unavco.org/software/teqc/teqc.html#executables
or a version of teqc older than 18 Mar 2008.

or

b) Edit the RINEX obs file so that the "REC # / TYPE / VERS"
header line occurs _before_ the "# / TYPES OF OBSERV" header line
if you need to continue to qc RINEX using a teqc version from
19 Mar 2008 to before 22 Oct 2008.

You only need to do (a) or (b) -- not both -- and then if and only if
both conditions (1) and (2) are true, and also note, this is
a bug regarding qc of RINEX, i.e. not translation, etc.

cheers,
--lou

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Louis H. Estey, Ph.D.              office:  [+001] 303-381-7456
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"If the universe is the answer, what is the question?"
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