Radarbox delayed data after powered for a long time

[homestea]

I have noticed that if i keep my Radarbox powered and on for and extended period (about 12 or more hours) it seems the live ADS-B traffic being recieved by the unit gets delayed by at least 10-20 seconds.  To remedy this I just unplug the radarbox usb and plug it in again and I see that the delay goes away and the positions are again live.  Has anybody else noticed this effect?  I notice this effect because i like to leave the radarbox on 24-7 to share my data with other users.

[Allocator]

No, I've never had this problem.  How do you know that there is a 10-20 second delay?  Are you comparing this with aircraft you can see?

[AirNav Support]

We have never seen this issue either, we have dozens of machines runing 24/7, some at airports and used by certain company who need accurate data and its never been mentioned to us by them either.

[pure3000]

Hi there, im still quite new to this got my box for christmas.
Now at the bottom left of the airnav screen near the hardware connected box i have a message that counts down for 30 seconds is this the same thing as mentioned above?

[homestea]

No, I've never had this problem.  How do you know that there is a 10-20 second delay?  Are you comparing this with aircraft you can see?

Yes, I'm comparing the display to what i am seeing out my window.  I can then unplug the USB and reconnect it and instantly I see a jump in the program to the correct aircraft position. I am running windows 7, so i wonder it there may be a bug of some kind where a buffer is filling then begins to delay.

[Spaice]

Have you changed the default setting for the refresh, ie higher than 1000ms? the higher the number the longer the refresh delay.

[eggplant]

Hmm.  I am using Windows 7 and my ANRB is normally on 24/7. I haven't noticed any delay. I have some landmarks which I can view from my window to gauge the correct position of aircraft - I'll keep a close eye next time we get a clear day, so could be six months or so....and report further then.

[homestea]

Have you changed the default setting for the refresh, ie higher than 1000ms? the higher the number the longer the refresh delay.

For some reason, mine was set to 4000ms!! I dont know how that happened! I changed it back to 1000.  I will let you know if that was causing the problem! Thanks for the feedback!

[Aerotower]

Hi! Been there a few times to leave the RB on and when I get home, I see that in MyLog was a cut in the receipt list.

When happen again put here a screenshot.

[jannuh]

Got my RB as of 6th Sept., runs now for at least 2 months without seeing it (its located in the loft ;-) )

[homestea]

after changing the refresh to 1000, I am still experiencing a build up of delay over just a couple hours.  This delay translates to about a 10-15 second delay of actual aircraft position and what is being displayed on the map.  I dont know what i can do to resolve this short of uninstalling the program and drivers and reinstalling everything from scratch.  Is there some kind of usb data speed setting, perhaps my usb port is operating at a slower baud rate of what the radarbox is sending it out, and thus putting excess data into a buffer, causing the delay?! I'm very puzzled why it is acting ths way and nobody else seems to have this problem.

[homestea]

I also notice that when I listen to the control tower departure, and the departing aircraft says the altitude it is climing through, it is often off by 500ft or more from what the softwaare says.  This applies to mode-s aircraft as well as ads-b aircraft.

[Allocator]

I also notice that when I listen to the control tower departure, and the departing aircraft says the altitude it is climing through, it is often off by 500ft or more from what the softwaare says.  This applies to mode-s aircraft as well as ads-b aircraft.

When an aircraft is climbing out, the controller is required to verify the Mode C (the level readout) displayed on the screen compared to the level the pilot says he is passing.  The tolerance for this is 300ft - what you see on the screen must be within 300ft of what the pilot says.  To get within 500ft using a non-calibrated but of kit that costs less than GBP400 is pretty good!

In level flight the tolerance is 200ft.

See the link below for more details regarding verification of Mode C and requirements for assuming an aircraft is level:

http://www.ecacnav.com/content.asp?PageID=395

(it's been a while since I've put this into practice, so I'll sure that somebody more current will correct me here if I've got this wrong!)

[DaveReid]

To get within 500ft using a non-calibrated but of kit that costs less than GBP400 is pretty good!

Not sure what amount of calibration of a RB/SBS would produce or eliminate any difference between the altitude the aircraft is transmitting and what the box is decoding, but point taken.

It's also worth bearing in mind that a departing aircraft could easily be climbing out at 3000fpm, so in the 5 seconds or so that a pilot takes to report his callsign and altitude he's already 250' higher than he says he is  :-)

[Allocator]

To get within 500ft using a non-calibrated but of kit that costs less than GBP400 is pretty good!

Not sure what amount of calibration of a RB/SBS would produce or eliminate any difference between the altitude the aircraft is transmitting and what the box is decoding, but point taken.

Time taken to process the data would be critical here.  This would be a specified requirement for ATC use, but is largely irrelevant with a 'hobby' item.

The Hi-Brite display in the ATC Visual Control Room (VCR) is a slave using the same data shown downstairs in Approach, but you are not allowed to control on it, as it isn't calibrated for this use.  You can use it to gain situational awareness and to identify zone crossers, but you can't actually 'control' with it.