In the past few months of working with CORS data I've always downloaded (CORS) from midnight CST (0600 utc) to normally 8:00 a.m. CST (1400 UTC). No problems experienced in downloading this time segment. I've also downloaded a few "daytime" sessions with no problems. Now I've come upon a problem. It seems that no matter what I do, I cannot download (saturday night) data from 0400 utc to 0800 utc for several CORS sites. The data comes in on Ashtech Solutions 2.5 from 0600 utc to 0800 utc. I thought this may have been due to the fact I was wotking with a PM2 file from 02.027 session so I tried downloading the same CORS segment to another file with Locus data (so as not to be possibly corrupted by whatever bug the PM2 may have). Nope, still no go. Then I tried a different saturday night - 02.020. Same problem again. The data would not come up in AS2.5 before 0600 UTC. The only common factor now appears to be the three CORS sites I'm having trouble with are 5 second epochs- ARL5, HOUS and BEA5. The full 0400 - 0800 data I tried for DQUA and WNFL came up o.k.
I realize the PM2 has a minor "quirk" on Saturday night, but this ain't all PM2. Any clues???? I may need to resolve this before 02.034
Thanks for any ideas.
J.D.
p.s. anyone interested may try to download the CORS data from 02.027 between 0400 utc and 0800 utc. for the above mentioned stations. I'd really appreciate a solution
something is wierd with BEA5 I think.
In AS i loaded up the 24 hour file and with UTC selected and the time box at 0 then the file loads from 6am Jan 27 to 6 am jan 28.........?????????
The time box makes no difference with UTC selected.
With the time set at -6 then the file moves to 0:00 which makes me think the file is 6 hours off.........
Local correction - UTC =>
-0600 - 0000 = 1800 previous day
-0600 - 0600 = 0000 same day
or is it late and I'm thunking wrong ..
Anyway the files are at orgie in jd-tx subdirectory.
they have a gz extension. if you have a late version of Winzip it ought to open them. Otherwise you need to go to www.winzip.com and getit or goto the gz unzip sub-folder and get gzip.exe and run gzunzip in a dos window.
Didn't try the other CORS sites but don't use UFCORS and you get the files from the same place at NOAA....just a little bigger and messier.
If you have any trouble holler and I'll get and post the link.
Jimbo
PS: All 24 hours are there.
Modified By James Webb on 1/30/2002 at 10:43 PM
I don't thinlk the files are useable.
Somehow they got recorded with CST as the "UTC time" . When you try and match up with your receiver file they'll still show 6 hours difference......
I think
Jimbo
on the As 2.xx Settings misc screen....
it says LOCAL - UTC even though on the bottom of the Program manager window it gets it right....Local = UTC (-correction).
Jimbo
How could I have ever believed that the data files were recorded wrong.
;0]
Jimbo
ARL5, HOUS and BEA5 have one thing in common for sure......
Modified By James Webb on 1/30/2002 at 11:34 PM
Jimbo,
Start over with your explaining.
What's your verdict.
J.D.
When AS is set to UTC they come in at 0600 thru 3000 (0600 the next day ??) When they should be 0000 thru 2400.
I don't think they can be used....
Jimbo
Modified By James Webb on 1/30/2002 at 11:51 PM
Jimbo,
I tried changing the settings in AS2.5 from -6 to 0 and it made no difference. I always download the zipped CORS file directly to my project folder, and unzip the file in the folder. Then I "load gps data from disk". No matter what I try, I still can't get these files to bring any data in before 0600 utc.
Maybe we need more help. I didn't have this problem in original L1/CORS tests, but I only requested data from 0600 to 1400 for each CORS site. I'm not sure if 0600 is a migic number or what.
jd
switch the local/utc toggle and that is when the time changes.
But the CORS error is different...
it is complicated but I think I understand what happened at these three sites (maybe the same thing)
the UTC time for the files should be 0000 to 2400...midnite to midnite.
In reality they are stored as from 0600.027 to 0600.028, that is the 5 meg file ya see in the orgie folder. So when ya ask for 0400.027 thru 0600.027 it doesn't exist in the .027 file and therefore is not returned in the Zip file.
Now the question is ....
Is the storage time recorded in the files wrong or is the "save" time, when the computer saves the data and packs up the 24 hour file, set to do it at the wrong time ??
If you download from NOAA but using the "Standard download and get .026 I'll bet 0000.027 thru 0600.027 is included in this previous days file.
Jimbo
EDIT: I first thought the time saved in the data file was wrong...i think now it is much simpler...I think the data save was done at the wrong time !! Didn't ya say it kinda processed ith the 2 hours, which it wouldn't have done if my first thought was correct.
Modified By James Webb on 1/31/2002 at 12:14 AM
I use the UFCORS site and never noticed a problem. But, I either start data requests at 0600 for the "all nighters", or 1400 for 8 hour day sessions. This time I just decided to take advantage of the best constellation possible so I started my session a couple hours earlier than normal. Getting cut to 4 hours due to power constraints threw additional kink in the project.
I think you're on to something on the data storage time thing. I have noticed the time from 0000 to 0600 will be posted as available on the CORS homepage well in advance of the remainder of the data. I just never considered it as a potential problem.
JD
by the way, I can't even figure out how to access the data files you say are in jd-tx folder. remember, i'm a ftp rookie
Modified By J.D. Billings on 1/31/2002 at 12:19 AM
yeah, the stuff processed with the 2 hours it downloaded from the 3 TX stations and the 4 hours from the other 2 stations. No doubt the data is good, just not all that was requested. There again, I don't know if its Solutions or CORS.
As for the processed vectors, I had several that "fixed", rather than partial. just not nearly enough data for good position. i didn't spen a whole lot of time tweaking, but did get to the point the error estimates (for 2 unknowns) were all in the 0.5 foot range (N,E & Z) and the errors were all in that range. Not near enough data for megavector/L1 in my opinion.
jd
OK, its there. I don't know how to export just the 4 hours ya need but I have 48 hours of data in the jd-tx file with a .gz extension.
get on the site....this might work better
ftp://orgi:orgi@jimbo1.d2g.com
then double click on the jd-tx folder
now at the browser menu up top click on View and then details on the pulldown menu
this'll let ya see the extensions.
then mark a file and drag to your desktop/hard drive locaton or right click on a file and copy then paste to your desktop/hard drive location.
Jimbo
Ps: goes into AS just fine. I still think the Settings page has a minor error...isn't local time UTC-Local correction ?....or is it confusing layout ???
Modified By James Webb on 1/31/2002 at 12:43 AM
Daily Downloads
each cors site has its own sub-folder
if the 8th digit in the name is 0 then it is a 24 hour file. I think ya need all 3 files for the rinex loader to work.
Seems like you are having trouble trying to download file...keep connecting and disconnecting...don't know what to tell ya...just think of it as a temporary directory on your machine and try to copy like ya normally would.
Jimbo
PS: on the download site, use the UP TO A HIGHER LEVEL and then refresh unil ya get to the numbered (days of the year) folders. Once ya are there add it to your favorites.
Modified By James Webb on 1/31/2002 at 12:56 AM
I haven't been able to open the directory yet. when i double click on jd-tx/ at the top of the window (showing all 11 files) the "./" file is seperated from the rest by a dotted line.
and see what happens.
That might be a quirk in the FTP program.
ya should see
.
..
file 1
.
.
.
file 9
or something real close.
Jimbo
NOTE 6-8 is a subfolder and gz_unzip is a subfolder. The other 9 are files.
the . and .. are directory change type commands.
Modified By James Webb on 1/31/2002 at 1:06 AM
I just can't open the jd-tx/ folder to see the files inside
i see:
./
../
01-old messages/
jd-tx/
xx
xx
xx
i recognize the "." and ".." dos files
just can't seem to open my folder
I changed a setting, see if it helps.
shouldn't make a difference but....
jimbo
1. What program are ya FTP'n with ??
2. Try copying the whole jd-tx folder. I just cleaned it so it only has the gz files in it.
Jimbo
Modified By James Webb on 1/31/2002 at 1:22 AM
now i get "timed out"
earlier i tried to copy the whole folder. couldn't do it.
.
put the ftp://..... in the address window
got there via browser this time. I'm not sure about the brandyware software.
30 seconds with nothing to do and zzzzzzzzzzzzzzzzzzzzzz
i loaded up freeftp and it definetly has a bug changing to the second directory level....won't do it...not anything you did wrong for sure.
I'd suggest using the uninstall/remove and getting it off the machine.
looks like ya stared the download a coupla times...one timed out after 15± minutes. I show client (you) timed out.
Second looks like ya canceled the download after a coupla minutes.
Anyway,,,,,,
jimbo
This is some strange stuff. I uninstalled the freeftp software. I knew something wasn't quite right but figured it was me. I lost confidence in my computer skills about the time basica began to wain in pupularity. Definately by dos 5.0.
Now I can access the site from the browser, open directories, download files if I want, but won't I still need some breed of ftp software to upload files to the site? What do you recommend (I'll go back a re-read the discussion from the other night)?
As for CORS and their "timeline", the CORS download page should join days and parts of days. In my case there should be no problem with data from 0400 to 0800 utc. I still wonder if this is a "user software" problem concerning saturday data (maybe still in the 0000 to 0600 utc range).
jd
http://www.neotextsoftware.com/max-ftp_default.asp
How about the real problem. Help us with the CORS timeline deal. Using the UFCORS page to download time segments into AS2.5 seems to be a bit of a problem as you must have seen by wading through all this to get to the ftp stuff.
j.d.
thanks for the link, i'll try that next
J.D.,
I've had this problem before, and think it's a bug in the UFCORS download site (but can't be sure). As a result, I normally download 24-hour files. I'd suggest contacting them.
I've been using Max-FTP for a year, and like it a lot. It's freeware.
Regards,
Brian
JD,
you ought to be able to upload by just dragging and dropping/copy and paste onto the browser page from your hard drive once connected to the FTP site and changed to the jd-Tx subfolder.
The browser didn't use to handle FTP very well..95,early 98, but it seems to be working in current versions decently.
I think the UFCORS "problem" isn't going away. Maybe ask for 2800.026 (4 am 027) for 2 hours and 0600.027 for 2 hours ????
;-]
Jimbo