Author Topic: Some Targets not appearing on Skydemon  (Read 604 times)

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #15 on: April 03, 2021, 06:27:13 pm »
Ok Peter. Sorry about that. I also seem to have a similar problem as Geffory C in a recent post.
 No ADSB traffic seen on vector over 3 Separate flights over 3 different days. Today I was flying for almost an hour north of EMA around Trent and Gamston VORs at around 2300 feet. I will try and send some screen shots of Vector later. Pilotaware and Skyecho2 look ok.

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #16 on: April 03, 2021, 06:30:37 pm »
Hope this is better

exfirepro

Re: Some Targets not appearing on Skydemon
« Reply #17 on: April 03, 2021, 10:30:51 pm »
Hi Again Dave,

That’s much better thanks. No sign of any obvious issues with any of your settings there, though as I have said earlier, I would open your range and altitude filters wide until we know you are receiving and displaying traffic.

I will take a look at the database and see what it is telling me and report back.

Regards

Peter

« Last Edit: April 03, 2021, 11:49:25 pm by exfirepro »

exfirepro

Re: Some Targets not appearing on Skydemon
« Reply #18 on: April 03, 2021, 11:36:28 pm »
OK Dave,

My initial search for your aircraft ID shows reception of Mode-S (via MLAT) and PilotAware by the ATOM-GRID Network since January 2020 and PilotAware and ADSB (presumably CAP1391 from your SkyEcho) from early December. Strangely, there are no Mode-S MLAT reports from any flights after 7 October 2020 (despite the fact that there are reports from PilotAware/ADSB flights since that date), which would suggest that your transponder has either become defective or not been used since October 2020  ???

The two most recent flights I can see are reporting PAW and ADSB transmissions on the 29th March solely from PWEGBN and at a maximum range of 4Km for both (which would imply a short very local flight) and on the 30th March from PWArnold (North Nottingham) - PAW only at up to 11Km, PWBostonW - PAW only a few contacts at ~60 to 64Km, PWDarley -  both PAW and ADSB at up to 55Km, and PWEGBN - both PAW and ADSB at up to 40Km and 37Km respectively. These ranges are consistent with what I can see from your (as yet unpublished) Vector Diagrams. I would deduce from these results and the Vector Diagrams that both units were operating in ‘portable’ mode, probably on the coaming or right-hand front window of the aircraft. Does this sound right? Reference to the Vector Diagrams should help guide you as to how you might reposition the units to improve coverage.

It doesn’t of course explain why you are still reporting seeing no 1090MHz traffic on SkyDemon. Are you seeing any 1090MHz traffic reporting on the PAW Traffic Screen? Whether you are or not, a screenshot(s) of the PAW Traffic screen - taken when the unit has been running for a reasonable length of time and in an area where you know there was definitely 1090MHz traffic active might be helpful. If not, I would suspect an issue with the 1090MHz antenna, pigtail or SDR, though the Home Screen is showing 1090 signals had been received (though at the time that screenshot was taken the unit had only been running for 3 minutes). The first thing to check is that these are all properly connected / seated in the USB slot, which you can do fairly easily by opening the end cover of your Rosetta.

Let us know how you get on.

Best Regards

Peter
« Last Edit: April 04, 2021, 07:22:37 am by exfirepro »

exfirepro

Re: Some Targets not appearing on Skydemon
« Reply #19 on: April 04, 2021, 11:20:23 am »
Dave,

A Quick update.

Yesterday’s flight also now showing in our records (only appear after midnight at my access level).

Results are pretty similar to 30th March, other than a single report at between 20 and 30Km from PWQuorn and a couple at less than 10Km from PWWestBfd.

Peter

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #20 on: April 04, 2021, 12:04:55 pm »
 Thanks for your very quick response Peter. On the 29 March I only flew a few circuits at EGBN.(after lockdown).On the 30th of March I flew to Gamston and back. On the third of April (yesterday) I flew for an hour around north Derbyshire and Nottinghamshire. As far as I know my transponder (Garmin 328) is working ok as I’ve had no complaints from EMA radar.
My hex code is 401C1B. Is it possible for you to check Vector on my behalf. Yesterday shows much more activity.
You are correct about my set up. The 1090 antenna is mounted perpendicular on the front glare shield with very clear view of the sky. However the dipole aerial is mounted on the right hand side window(high up).
I’ll check all the connections again as you suggest and take a screen shot of thePAW traffic screen over a longer period of time.What do you mean by pigtail,SDR.?
Kind regards Dave.

exfirepro

Re: Some Targets not appearing on Skydemon
« Reply #21 on: April 05, 2021, 06:15:26 pm »
Hi Again Dave,

Sorry for my prolonged 'absence' - I have been rebuilding a Ground Station ready to re-install at Balado Airfield (near Kinross). The previous one had to be taken down several months ago as they were demolishing the tower which it was mounted on and I'm desperate to get the new one up as flying has resumed (albeit on a limited basis as we're still not allowed to travel outside our own local authority areas up here!

Please ignore my earlier comment about your Mode-S flights after 7 October 2020 and accept my apologies. It turns out it was nothing to do with your transponder, but apparently a change at our end in the way the Network handles Mode-S data, which no-one thought to tell me about!

The 'pigtail' is the short peach-coloured cable which connects internally between the (shorter) 1090 antenna - or shorter dipole if you have changed to one of those - and the Software Defined Radio (SDR) - which is the smaller circuit board inside the end cover of PilotAware (with the (pigtail) cable plugged into it). This is the bit that receives 1090MHz Mode-C, Mode-S and ADS-B signals and passes them into PilotAware for processing. I just wanted you to check all is connected properly, though the fact that it was reporting when you took the shot of the Home Screen implies thay should be OK. The other circuit board inside the end cover by the way is the GPS receiver.

I'm a bit confused about your antennas. When you say ' the 1090 antenna is mounted perpendicular on the front glare shield with a clear view of the sky', I hope you mean orientated vertically - if it is horizontal, it will perform very poorly. Photos of the units and antennas in situ would clarify.

I have had a look at the Vector Plots for your PAW and SE2 transmissions (see attachments). The PAW one shows fairly good coverage and range (though there are a few 'blind spots' which could probably be improved. The SE2 transmission seems to be predominantly towards the front and RHSide. Other PA28 users have reported better coverage by fitting it to the RH Rear-side window, so that might be worth trying. Remember, you can filter your reports on Vector (by clicking on the Calendar Symbol at Top-Right of the Vector Screen) to only show your 'pre-change' and 'post change' results separately for comparison.

Hope this helps

Regards

Peter

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #22 on: April 05, 2021, 08:01:23 pm »
Hi Peter,
No problem with the delay. It is bank holiday after all and I know how busy you must all be. Your team is helping my friends set up a station at Leicester in the very near future I believe.
Thanks for explaining pigtail and SDR for me. The 1090 antenna is mounted vertically!.
I will try your suggestion and move SE2 to the rh rear window and check vector again post change.
I’ll look at all the connections again sometime this week and report back after further flights.
Much appreciated
Dave

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #23 on: April 08, 2021, 04:51:40 pm »
Hi Peter,
Been down to the airfield today and checked my connections etc. Took some screen shots as you recommended while on the ground. (Didn’t want to run my battery down to much) Any comments greatly appreciated
Regards Dave

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #24 on: April 08, 2021, 04:55:32 pm »
Resent

exfirepro

Re: Some Targets not appearing on Skydemon
« Reply #25 on: April 08, 2021, 10:53:37 pm »
Hi Again Dave,

Your first screenshot shows a good mixture of Mode S with PilotAware (G-CTCL - C S - P - - -), ADS-B (G-HANC - C S A- - -) both of which were well within range and should therefore have been showing on SD as moving aircraft. There were also a load of 'Mode S' equipped aircraft (designated by CS -----) which unfortunately were all too weak to be reported on screen (identified by very low SIG (signal strength), so would not be presented to your Nav System.

The second Traffic Screenshot again shows G-CTCL and G-HANC - both indicating that they would be displayed, as would the other ADSB aircraft (C S A---) G-EUPJ and N721AN, but ONLY if they were within the range of your tablet screen (depends on your zoom scale). The other Mode S aircraft (C S -----) were again all to weak to be presented to your Nav Display.

But this certainly proves that your PilotAware is working as designed - just not enough aircraft in range.

Give it another try once you can get flying with the settings advised previously and let us know how you get on.

Best Regards

Peter

Dave jones

Re: Some Targets not appearing on Skydemon
« Reply #26 on: April 09, 2021, 11:27:43 am »
Thanks Peter for all your help. Very useful.
Regards Dave