If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Implausible Time Records
For my last three flights I've been getting a message from OLC warning
of implausible time records in the igc file.ツ* Does anyone know what this means and what I might do to correct the problem? I've asked the question on the ClearNav forum but haven't gotten a reply yet. Here's a link to the file if that helps: https://www.dropbox.com/s/erm01jilim...8Q-01.IGC?dl=0 -- Dan, 5J |
#2
|
|||
|
|||
Implausible Time Records
On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote:
For my last three flights I've been getting a message from OLC warning of implausible time records in the igc file.ツ* Does anyone know what this means and what I might do to correct the problem? I've asked the question on the ClearNav forum but haven't gotten a reply yet. Here's a link to the file if that helps: https://www.dropbox.com/s/erm01jilim...8Q-01.IGC?dl=0 -- Dan, 5J Noticed it was from the vario. I'll use a vario file today and see... Jim |
#3
|
|||
|
|||
Implausible Time Records
Yes, it was from the vario which just started acting up.ツ* The ClearNav
II display's USB stick did not have the flight.ツ* I may have neglected to download that. Lately I've been getting a boatload of GPS drop outs.ツ* Maybe that's because I'm close to the source of the interference testing or maybe it's because I've cut my antennae cables to length in my cockpit.ツ* I now seem to recall reading that one should not shorten the cables. I know about reflections due to wavelength/transmission line length, but I was unaware that that would affect reception.ツ* Do I need to acquire new antennae?ツ* The antenna that came with my PF portable was 10 meters long!ツ* Who needs a big bundle of cable under the panel? On 5/5/2019 9:49 AM, JS wrote: On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote: For my last three flights I've been getting a message from OLC warning of implausible time records in the igc file.ツ* Does anyone know what this means and what I might do to correct the problem? I've asked the question on the ClearNav forum but haven't gotten a reply yet. Here's a link to the file if that helps: https://www.dropbox.com/s/erm01jilim...8Q-01.IGC?dl=0 -- Dan, 5J Noticed it was from the vario. I'll use a vario file today and see... Jim -- Dan, 5J |
#4
|
|||
|
|||
Implausible Time Records
At 16:26 05 May 2019, Dan Marotta wrote:
Yes, it was from the vario which just started acting up.ツ* The ClearNav II display's USB stick did not have the flight.ツ* I may have neglected to download that. Lately I've been getting a boatload of GPS drop outs.ツ* Maybe that's because I'm close to the source of the interference testing or maybe it's because I've cut my antennae cables to length in my cockpit.ツ* I now seem to recall reading that one should not shorten the cables. I know about reflections due to wavelength/transmission line length, but I was unaware that that would affect reception.ツ* Do I need to acquire new antennae?ツ* The antenna that came with my PF portable was 10 meters long!ツ* Who needs a big bundle of cable under the panel? On 5/5/2019 9:49 AM, JS wrote: On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote: For my last three flights I've been getting a message from OLC warning of implausible time records in the igc file.ツ* Does anyone know what this means and what I might do to correct the problem? I've asked the question on the ClearNav forum but haven't gotten a reply yet. Here's a link to the file if that helps: https://www.dropbox.com/s/erm01jilim...8Q-01.IGC?dl=0 -- Dan, 5J Noticed it was from the vario. I'll use a vario file today and see... Jim -- Dan, 5J Looking at the file, there is an out-of-sequence issue: Checking File C:\Users\Public\Documents\GPS\2019-05-04-CNI-V8Q-01.IGC --------------------------------------------------------------------- Out of Sequence Error - B1903383458935N10559992WA0184701874001999104104113 000 B1903393458935N10600013WA0184901876001999112112116 000 B1903373458935N10600035WA0185101877001999115115119 000 B1903383458936N10600057WA0185301878001999119119122 000 Could this be the issue? |
#5
|
|||
|
|||
Implausible Time Records
I don't see what you're seeing.ツ* But how could records be out of
sequence?ツ* Maybe because my position apparently reversed while thermalling during a GPS outage and getting one or two hits and then another drop out, etc.? On 5/5/2019 10:43 AM, Tim Newport-Peace wrote: At 16:26 05 May 2019, Dan Marotta wrote: Yes, it was from the vario which just started acting up.テつ* The ClearNav II display's USB stick did not have the flight.テつ* I may have neglected to download that. Lately I've been getting a boatload of GPS drop outs.テつ* Maybe that's because I'm close to the source of the interference testing or maybe it's because I've cut my antennae cables to length in my cockpit.テつ* I now seem to recall reading that one should not shorten the cables. I know about reflections due to wavelength/transmission line length, but I was unaware that that would affect reception.テつ* Do I need to acquire new antennae?テつ* The antenna that came with my PF portable was 10 meters long!テつ* Who needs a big bundle of cable under the panel? On 5/5/2019 9:49 AM, JS wrote: On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote: For my last three flights I've been getting a message from OLC warning of implausible time records in the igc file.テつ* Does anyone know what this means and what I might do to correct the problem? I've asked the question on the ClearNav forum but haven't gotten a reply yet. Here's a link to the file if that helps: https://www.dropbox.com/s/erm01jilim...8Q-01.IGC?dl=0 -- Dan, 5J Noticed it was from the vario. I'll use a vario file today and see... Jim -- Dan, 5J Looking at the file, there is an out-of-sequence issue: Checking File C:\Users\Public\Documents\GPS\2019-05-04-CNI-V8Q-01.IGC --------------------------------------------------------------------- Out of Sequence Error - B1903383458935N10559992WA0184701874001999104104113 000 B1903393458935N10600013WA0184901876001999112112116 000 B1903373458935N10600035WA0185101877001999115115119 000 B1903383458936N10600057WA0185301878001999119119122 000 Could this be the issue? -- Dan, 5J |
#6
|
|||
|
|||
Implausible Time Records
Dan,
Open your file with a text editor and search for "B190338" This will put you in the right area. In each record, after the letter B, the next six bytes are the time. After B190339 the time jumps back to B190337, which is odd, and leads to there being two records with a time of 190338, and also 190339. Odd, but I have seen this before. Maybe you can avoid it in future by setting a longer fix interval, even 2 seconds might help, but no promises. I am not seeing any GPS outage around that time. This would be shown by the Letter "A" in the 25th byte changing to a "V". Although it does not help a lot, the sequence error seems to happen as you left the ground, so I guess you were not reversing turns? I'm not saying this is what OLC are complaining about, just that it is odd and it might be. Tim. -- At 17:06 05 May 2019, Dan Marotta wrote: I don't see what you're seeing.ツ* But how could records be out of sequence?ツ* Maybe because my position apparently reversed while thermalling during a GPS outage and getting one or two hits and then another drop out, etc.? On 5/5/2019 10:43 AM, Tim Newport-Peace wrote: At 16:26 05 May 2019, Dan Marotta wrote: Yes, it was from the vario which just started acting up.テつ* The ClearNav II display's USB stick did not have the flight.テつ* I may have neglected to download that. Lately I've been getting a boatload of GPS drop outs.テつ* Maybe that's because I'm close to the source of the interference testing or maybe it's because I've cut my antennae cables to length in my cockpit.テつ* I now seem to recall reading that one should not shorten the cables. I know about reflections due to wavelength/transmission line length, but I was unaware that that would affect reception.テつ* Do I need to acquire new antennae?テつ* The antenna that came with my PF portable was 10 meters long!テつ* Who needs a big bundle of cable under the panel? On 5/5/2019 9:49 AM, JS wrote: On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote: For my last three flights I've been getting a message from OLC warning of implausible time records in the igc file.テつ* Does anyone know what this means and what I might do to correct the problem? I've asked the question on the ClearNav forum but haven't gotten a reply yet. Here's a link to the file if that helps: https://www.dropbox.com/s/erm01jilim...8Q-01.IGC?dl=0 -- Dan, 5J Noticed it was from the vario. I'll use a vario file today and see... Jim -- Dan, 5J Looking at the file, there is an out-of-sequence issue: Checking File C:\Users\Public\Documents\GPS\2019-05-04-CNI-V8Q-01.IGC --------------------------------------------------------------------- Out of Sequence Error - B1903383458935N10559992WA0184701874001999104104113 000 B1903393458935N10600013WA0184901876001999112112116 000 B1903373458935N10600035WA0185101877001999115115119 000 B1903383458936N10600057WA0185301878001999119119122 000 Could this be the issue? -- Dan, 5J |
#7
|
|||
|
|||
Implausible Time Records
Thanks Tim
I'll increase my time interval to 2 seconds and see if that helps. Strange that the igc file does not show GPS drop outs since my ClearNav screen went white with the caption (something like) No GPS.ツ* Zero satellites.ツ* And the ClearNav vario said, "Warning no GPS".ツ* The PowerFlarm portable screen also went blank with a "Zero satellites" message. On 5/5/2019 1:05 PM, Tim Newport-Peace wrote: Dan, Open your file with a text editor and search for "B190338" This will put you in the right area. In each record, after the letter B, the next six bytes are the time. After B190339 the time jumps back to B190337, which is odd, and leads to there being two records with a time of 190338, and also 190339. Odd, but I have seen this before. Maybe you can avoid it in future by setting a longer fix interval, even 2 seconds might help, but no promises. I am not seeing any GPS outage around that time. This would be shown by the Letter "A" in the 25th byte changing to a "V". Although it does not help a lot, the sequence error seems to happen as you left the ground, so I guess you were not reversing turns? I'm not saying this is what OLC are complaining about, just that it is odd and it might be. Tim. -- Dan, 5J |
#8
|
|||
|
|||
Implausible Time Records
On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
Thanks Tim I'll increase my time interval to 2 seconds and see if that helps. Strange that the igc file does not show GPS drop outs since my ClearNav screen went white with the caption (something like) No GPS.ツ* Zero satellites.ツ* And the ClearNav vario said, "Warning no GPS".ツ* The PowerFlarm portable screen also went blank with a "Zero satellites" message. On 5/5/2019 1:05 PM, Tim Newport-Peace wrote: Dan, Open your file with a text editor and search for "B190338" This will put you in the right area. In each record, after the letter B, the next six bytes are the time. After B190339 the time jumps back to B190337, which is odd, and leads to there being two records with a time of 190338, and also 190339. Odd, but I have seen this before. Maybe you can avoid it in future by setting a longer fix interval, even 2 seconds might help, but no promises. I am not seeing any GPS outage around that time. This would be shown by the Letter "A" in the 25th byte changing to a "V". Although it does not help a lot, the sequence error seems to happen as you left the ground, so I guess you were not reversing turns? I'm not saying this is what OLC are complaining about, just that it is odd and it might be. Tim. -- Dan, 5J That smells of GPS jamming. Check this page. https://www.navcen.uscg.gov/pdf/gps/...terference.pdf I did not have a problem with the vario file today. My antenna has a shortened cable to a MECA divider, then a short SMA-SMA link cable. Jim |
#9
|
|||
|
|||
Implausible Time Records
Yes, the GPS jamming usually centers around Alamogordo and ranges out to
about 400 nm.ツ* Moriarty is well within that area.ツ* I've asked other local pilots and they don't report so many drop outs. Maybe there are just too many GPS antennae in my ship.ツ* I'll take a look at a divider for everything except the ADS-B WAAS GPS.ツ* Its antenna is mounted aft of the engine in the Stemme.ツ* The rest are on or under the glare shield. On 5/5/2019 7:42 PM, JS wrote: On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote: Thanks Tim I'll increase my time interval to 2 seconds and see if that helps. Strange that the igc file does not show GPS drop outs since my ClearNav screen went white with the caption (something like) No GPS.ツ* Zero satellites.ツ* And the ClearNav vario said, "Warning no GPS".ツ* The PowerFlarm portable screen also went blank with a "Zero satellites" message. On 5/5/2019 1:05 PM, Tim Newport-Peace wrote: Dan, Open your file with a text editor and search for "B190338" This will put you in the right area. In each record, after the letter B, the next six bytes are the time. After B190339 the time jumps back to B190337, which is odd, and leads to there being two records with a time of 190338, and also 190339. Odd, but I have seen this before. Maybe you can avoid it in future by setting a longer fix interval, even 2 seconds might help, but no promises. I am not seeing any GPS outage around that time. This would be shown by the Letter "A" in the 25th byte changing to a "V". Although it does not help a lot, the sequence error seems to happen as you left the ground, so I guess you were not reversing turns? I'm not saying this is what OLC are complaining about, just that it is odd and it might be. Tim. -- Dan, 5J That smells of GPS jamming. Check this page. https://www.navcen.uscg.gov/pdf/gps/...terference.pdf I did not have a problem with the vario file today. My antenna has a shortened cable to a MECA divider, then a short SMA-SMA link cable. Jim -- Dan, 5J |
#10
|
|||
|
|||
Implausible Time Records
Jamming is directed skyward, they're not taking out car gps's in a 400
nm radius. If you're getting bad time stamps just at liftoff, it's not likely caused by jamming. I'm suspicious of your cut-down gps cables, those are tiny wires to be working on. On 5/6/19 9:08 AM, Dan Marotta wrote: Yes, the GPS jamming usually centers around Alamogordo and ranges out to about 400 nm.ツ* Moriarty is well within that area.ツ* I've asked other local pilots and they don't report so many drop outs. Maybe there are just too many GPS antennae in my ship.ツ* I'll take a look at a divider for everything except the ADS-B WAAS GPS.ツ* Its antenna is mounted aft of the engine in the Stemme.ツ* The rest are on or under the glare shield. On 5/5/2019 7:42 PM, JS wrote: On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote: Thanks Tim I'll increase my time interval to 2 seconds and see if that helps. Strange that the igc file does not show GPS drop outs since my ClearNav screen went white with the caption (something like) No GPS.ツ* Zero satellites.ツ* And the ClearNav vario said, "Warning no GPS".ツ* The PowerFlarm portable screen also went blank with a "Zero satellites" message. On 5/5/2019 1:05 PM, Tim Newport-Peace wrote: Dan, Open your file with a text editor and search for "B190338" This will put you in the right area. In each record, after the letter B, the next six bytes are the time. After B190339 the time jumps back toツ* B190337, which is odd, and leads to there being two records with a time of 190338, and also 190339. Odd, but I have seen this before. Maybe you can avoid it in future by setting a longer fix interval, even 2 seconds might help, but no promises. I am not seeing any GPS outage around that time. This would be shown by the Letter "A" in the 25th byte changing to a "V". Although it does not help a lot, the sequence error seems to happen as you left the ground, so I guess you were not reversing turns? I'm not saying this is what OLC are complaining about, just that it is odd and it might be. Tim. -- Dan, 5J That smells of GPS jamming. Check this page. https://www.navcen.uscg.gov/pdf/gps/...terference.pdf I did not have a problem with the vario file today. My antenna has a shortened cable to a MECA divider, then a short SMA-SMA link cable. Jim |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
All US Records are Now Motor Glider Records | Tango Eight | Soaring | 99 | March 23rd 17 12:07 PM |
OT 4 airport round robin - time lapsed / real time with ATC COMS -video | A Lieberma[_2_] | Owning | 0 | August 30th 09 12:26 AM |
OT 4 airport round robin - time lapsed / real time with ATC COMS -video | [email protected] | Instrument Flight Rules | 0 | August 30th 09 12:26 AM |
4 airport round robin - time lapsed / real time with ATC COMS - video | [email protected] | Piloting | 0 | August 30th 09 12:25 AM |
they took me back in time and the nsa or japan wired my head and now they know the idea came from me so if your back in time and wounder what happen they change tim liverance history for good. I work at rts wright industries and it a time travel trap | tim liverance | Military Aviation | 0 | August 18th 03 12:18 AM |