New Zealand Radar

[nzfatmatt]

Screenshot from 2014-03-29 17:19:42.jpg

Are my eyes working. A rough measurement to Christchurch on Google Earth has nearly 700km. Or is F-NZCH2 been taking something today! Getting close to the Chatham Islands now. I think someone should move out there

[Eule]

You are right, I had some exceptional coverage in that direction before. It goes beyond my SBSplotters range of 360nm.

Not sure how that is possible. I am on a sand dune and there is nothing in the way in that direction, but by my calculations it should be below the horizon. My adsbScope recorded the last position at 397nm (715km). I think that might be a record for me.

20140329_SBSplotter.jpg

400nm

[Oblivian]

Good atmospherics atm with this high pressure. But, it may also have just handed over and still crediting the last one, which does happen

Sent from my GT-I9300 using Tapatalk

[nzfatmatt]

Screenshot from 2014-03-29 17:39:44.jpg

That's it just before it disappeared a couple of minutes later.

[Petenz]

Best I ever had was a skip to 500NM south east; then a true reading at 275 NM after a few more skips at 400 Nm. The plane was QF A27 at FL380. That was the summer before this and my DPD antenna had just been put up using the Beast. I have misplaced the Jpg so cannot show .

[Eule]

Best I ever had was a skip to 500NM south east; then a true reading at 275 NM after a few more skips at 400 Nm. The plane was QF A27 at FL380. That was the summer before this and my DPD antenna had just been put up using the Beast. I have misplaced the Jpg so cannot show .

What do you mean by skip?

On a different note, I noticed that the log of my FR24 box has changed, it now suddenly has some lines referring to MLAT in it.
Such as:
2014-03-29 04:44:26 | [mlat][i]Stats 0/0

Could that mean that they are testing MLAT in New Zealand?

Is there a way to find out if this is happening?

[Petenz]

Mlat is used at Queenstown (due to the awkward terrain) and has been for some time I believe. I know that the NZ Airways Corp are in the process of installing stations on prominent hills in the South Island , I guess this is instead of putting ADSB in their older aircraft they will use a form of Mlat to carry through until adsb ( which comes installed in all the replacement acft) is the norm. I understand that the mechanical Radar stations are to be discontinued when ADSB and Mlat are well installed.
The term 'skip' I used to denote contact by radio waves from an unusual distance which probably has bounced off the 'heavyside' layer somewhere in the stratosphere and then come back to ones receiver. Someone correct me if I am wrong as I am no expert on radio wave behaviour.

[JackL]

Mlat is used at Queenstown (due to the awkward terrain) and has been for some time I believe. I know that the NZ Airways Corp are in the process of installing stations on prominent hills in the South Island , I guess this is instead of putting ADSB in their older aircraft they will use a form of Mlat to carry through until adsb ( which comes installed in all the replacement acft) is the norm. I understand that the mechanical Radar stations are to be discontinued when ADSB and Mlat are well installed.
The term 'skip' I used to denote contact by radio waves from an unusual distance which probably has bounced off the 'heavyside' layer somewhere in the stratosphere and then come back to ones receiver. Someone correct me if I am wrong as I am no expert on radio wave behaviour.

The term you are looking for is tropospheric ducting. The vast majority of duct-producing inversions lie between 450 and 1500 m (1500 to 5000 ft) with a few between 1500 and 3000 m (5000 to 10,000 ft). I've had some amazing distant contacts above 1ghz thanks to the phenomenon.

[Eule]

Mlat is used at Queenstown (due to the awkward terrain) and has been for some time I believe. I know that the NZ Airways Corp are in the process of installing stations on prominent hills in the South Island , I guess this is instead of putting ADSB in their older aircraft they will use a form of Mlat to carry through until adsb ( which comes installed in all the replacement acft) is the norm. I understand that the mechanical Radar stations are to be discontinued when ADSB and Mlat are well installed.

Sorry, I was referring to FR24 MLAT (the MLAT capability of the FR24 boxes that is already being used in Europe). I don't think that has been used in New Zealand yet. I think it needs at least 4 FR24 units with overlapping coverage and some minimum baseline distance. With F-NZGT1 great coverage there might be some overlapping areas from 4 FR24 receivers.

Does anybody know how one recognises whether the FR24 unit has been activated for MLAT?

[Petenz]

Sorry, I was referring to FR24 MLAT (the MLAT capability of the FR24 boxes that is already being used in Europe). I don't think that has been used in New Zealand yet. I think it needs at least 4 FR24 units with overlapping coverage and some minimum baseline distance. With F-NZGT1 great coverage there might be some overlapping areas from 4 FR24 receivers.

It is a pity that your FR24 Mlat program is not compatible with the PlanePlotter Mlat programs already being used in NZ.

[nzfatmatt]

I saw a Mount Cook out of Rotorua earlier and noticed it was down to ground level on F-NZRO1 so looks like another hole filled

[nzfatmatt]

I'm still mucking around and experimenting with NZWN5 and a few days back changed out the "older" e4000 based dongle for a new R820T based NooElec dongle. That change has made a huge difference to it's coverage, with an indoor colinear antenna it's doing almost as well in some cases as my Beast with the DPD outdoor antenna. The Pi/dump1090 combo is working just fine too.

Been reading through the whole of the NZ thread. Taken a little while. Thanks for this suggestion. Currently have the aerial that came with the DVB-T in the window. Was running on the E4000 and had pretty crap reception and then changed over to the R820T which we had lying around but weren't using and noticed a large improvement. North went from Kapiti Island to Bulls and South from finals to 34 to Lake Grassmere.

Do have a DPD antenna coming so hopefully with that on the roof will see more.

I am near the Karori Wildlife Sanctuary at 200m with a view of the terminal through a gap in the hills.

[North Borneo Radar]

Been reading through the whole of the NZ thread. Taken a little while. Thanks for this suggestion. Currently have the aerial that came with the DVB-T in the window. Was running on the E4000 and had pretty crap reception and then changed over to the R820T which we had lying around but weren't using and noticed a large improvement. North went from Kapiti Island to Bulls and South from finals to 34 to Lake Grassmere.

Do have a DPD antenna coming so hopefully with that on the roof will see more.

I am near the Karori Wildlife Sanctuary at 200m with a view of the terminal through a gap in the hills.

Well done. I did the same more than 1 year ago, going through the whole thread of NZ Radar but that was probably 70++ pages then. Now it's 114 pages! It's the thread I like most after New Feeder Spotted really as the discussions are good. Seems like the dpd antenna is the antenna of choice for fellow New Zealanders! Wow...

[BPO]

The term you are looking for is tropospheric ducting. The vast majority of duct-producing inversions lie between 450 and 1500 m (1500 to 5000 ft) with a few between 1500 and 3000 m (5000 to 10,000 ft). I've had some amazing distant contacts above 1ghz thanks to the phenomenon.

This area (Mackenzie high country) experiences two common inversions of around 1,000m and 1,500m. These are one of the main reasons the site was selected for an optical astronomical observatory: Fog, low cloud, and most airborne particulates remain trapped beneath them, while the site at 1,800+m enjoys clear blue sky above them.

Some days both are active, and I pop out of the cloud at ~1,100m into crystal clear air, but with another layer almost immediately above (ceiling ~1,300m), so I'm in the gap between.

On another note, I've only just now discovered the feeder stats page for my FR24 and it's been interesting reading. For one thing, the most distant contact listed for the past week is "only" 228nm/420km, and to the NE. Yet almost all of the long range tracks I've watched on the FR24 map are off to the W/NW and have reached as far as ~300nm/550km.

Is this discrepancy an issue with FR24's mapping and/or coordinate system, or Google Maps ruler tool? Or are the stats incorrect? Whatever the case, it's making this all even more interesting.

[Eule]

On another note, I've only just now discovered the feeder stats page for my FR24 and it's been interesting reading. For one thing, the most distant contact listed for the past week is "only" 228nm/420km, and to the NE. Yet almost all of the long range tracks I've watched on the FR24 map are off to the W/NW and have reached as far as ~300nm/550km.

Is this discrepancy an issue with FR24's mapping and/or coordinate system, or Google Maps ruler tool? Or are the stats incorrect? Whatever the case, it's making this all even more interesting.

I found that the FR24 feeder stats under reports distances (or is maybe capped). Yesterday when I was getting close to 400nm as recorded by my SBSplotter and adsbScope it listed 328nm as my maximum range. The interactive polar graph doesn't quite work for me either, some range dots are not selectable.