AIS targets disappear after about 10 mins

JonJon

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I have a digital yacht AIS 100 linked up to my Acer netbook running OpenCPN. Windows 7 starter edition.
After about 10 mins my AIS targets disappear the AIS 100 still picks up transmissions (green light winks) but they are not displayed. If I unplug the AIS 100 from a USB port and plug it in another port back they come all fine for another 10 mins and then same again.

Anybody got a clue whats going on here, seems to work perfectly for a while and then stops displaying the data?
 
In OpenCPN AIS settings you can set various timeouts for stationary and lost targets. Could these settings be the culprit ? Try setting them all to higher values or uncheck the relevant boxes.
 
In OpenCPN AIS settings you can set various timeouts for stationary and lost targets. Could these settings be the culprit ? Try setting them all to higher values or uncheck the relevant boxes.

I so agree with this statement, the AIS setting should be verify in the AIS tab.
Which version of OpenCPN ?
sda
 
I don't think it is the culprit I have fiddled with these and the timeout seems to bear no relation to when I lose communication with the targets. I have downloaded the latest (beta version) of OpenCPN and the same problem happens. As I said I can get a temporary target reappearance if I change USB ports but after a few minutes its as tho the netbook ceases to listen to the AIS receiver I can still see the light twinkle on the receiver but no update. It also seems to get worse if the kit has been on for a few hours. It changes the kit from being an aid to a bit of a menace telling you there is nothing there when there is a superfast racing toward you at 20knots.
I have read elsewhere I don't seem to be alone with this issue and yet for others it seems to work fine.
 
Just for the record it is version 3.3.604 OpenCPN I am now using. There seems to be various theories about USB ports being interrupted by other programs in the computer -or aerial issues -whatever it is its a bit of a shame cos the nav part of open cpn works well.
 
I have not use opencpn so just some thoughts .Can you link the ais with a chartplotter , twinkly lights are just twinkly lights. The output from the ais needs to be confirmed as working correctly as well as the laptop. Also is there some sort of range for CPA. If all the the targets are calculated as being being above 1 miles CPA after 10 mins the system might not need to display them if CPA range is set for Example to .99 miles .
 
The CPA is set for 20 miles and I don't understand why it works initially and then gives up. Havent got a chartplotter only this kit. As I said it seems to get worse with time eventually not displaying targets at all even new ones I finish up fiddling with the USB ports instead of using the mark one eyeball - not good.
 
I would suggest you have a look at a simple data log program which will display the data coming from the AIS unit. You can then watch this and see if it is the AIS unit or cpn that is dropping out after 10 mins. I'm sure DY will have a free downloadable bit of software which will read the data coming from the AIS.
 
My guess would be some kind of operating system (or interaction of applications) problem rather than anything specific to the AIS or OpenCPN. This kind of thing is one of the reasons I tend to prefer dedicated kit.

Does Windows have some kind of system log that device problems might be recorded in, equivalent to dmesg or /var/log/messages on Unix?

Pete
 
The CPA is set for 20 miles and I don't understand why it works initially and then gives up. Havent got a chartplotter only this kit. As I said it seems to get worse with time eventually not displaying targets at all even new ones I finish up fiddling with the USB ports instead of using the mark one eyeball - not good.

why on earth do you req a CPA of 20 miles, mine is set @ 1/2 a mile & no targets beyond 10 miles
 
In Windows open Control Panel, then Power Options. Select the advanced settings for the current power plan, scroll down the list for the USB settings and ensure that Selective Suspend is set to Disabled. That stops Windows turning off the USB port to save power.
 
If you go into options|connections and click "show NMEA debug window" then a window will open showing any data the prog is receiving. Might be worth disabling any other connection apart from the ais. At least that will confirm if the issue is outside Opencpn (most likely) or not.
 
Just tried it Tony, many thanks I think you may have fixed my problem, it was set to turn off USB ports when on battery, why it didn't turn off the gps dongle I don't know but I always have that dongle connected to the single on the left side of the netbook maybe that one is not affected.
I am eternally grateful should you be In Preveza this week a pint of Alpha is yours!
 
Just tried it Tony, many thanks I think you may have fixed my problem, it was set to turn off USB ports when on battery, why it didn't turn off the gps dongle I don't know but I always have that dongle connected to the single on the left side of the netbook maybe that one is not affected.
I am eternally grateful should you be In Preveza this week a pint of Alpha is yours!

Don't count your chickens and all that! Post the Alpha to Crete please. :)

Glad it helped....possibly.
 
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