Show Posts

You can view here all posts made by this member. Note that you can only see posts made in areas to which you currently have access.


Messages - GeoffreyC

Pages: [1] 2 3 ... 8
1
Technical Support / Re: Clicking Sound in Headset
« on: November 26, 2021, 06:36:01 pm »
I’m also now wondering whether this could possibly be interference from electric fences. The airfield is surrounded by farm land and the clicks seem to be heard the most just after taking off, or on approach. Does anyone know how often electric fences pulse their volts into the wire? If it’s around twice a second I will go and look for one in the same area with an am radio!

Thanks.

Martin

I think electric fences usually 'click' once every couple of seconds.  If you walk up to the fence (but not touch it) you can usually hear the clicking, or at least you can with my wife's horse fence.

Cheers, Geoffrey

2
General Discussion / Re: Ofcom EMF licence changes
« on: August 23, 2021, 01:21:47 pm »
Hi Geoffrey

I ran the calculator with the Worst case scenario of 0.25 Watts (ERP) at 1% duty cycle
(we are much less than this)

the result cones out as

Low power. No further assessment required

Great thanks, that's really good to know. I think we're supposed to keep evidence of the EMF result in our aircraft reccords.  Could you upload a screenshot then we can all be compliant?

Geoffrey

3
General Discussion / Ofcom EMF licence changes
« on: August 20, 2021, 06:10:10 pm »
Earlier in the year Ofcom 'consulted' on changes to radio licences to bring in checking of EMF limits that might harm members of the general public (i.e. passengers we carry).

The BMAA and LAA both intervened as the Ofcom process was extremely confusing,  which resulted in a much clearer set of guidance from Ofcom https://www.ofcom.org.uk/__data/assets/pdf_file/0027/220797/emf-licence-condition-what-you-need-to-know-aeronautical-radio.pdf and this summary from the BMAA and LAA https://www.bmaa.org/news/bmaa-news/ofcom-electromagnetic-field--emf--licence-conditions

I received an email from Ofcom today advising that they are now varying my licence following this EMF consultation.

The PDF process covers what you need to do to be compliant for hand-held or panel radios and for transponders,  but for other equipment you have to run the EMF calculator on Ofcom's website https://www.ofcom.org.uk/manage-your-licence/emf/calculator
It asks a lot of questions about power output, etc,  which for my pilotaware I don't know.

Has the calculation been done already for PAW so we can share it and don't all have  to go through the same process?     Would need to be done for Atom ground stations as well I would imagine?

Thanks, Geoffrey

4
Is it possible for the RS232 converter to corrupt the signal somehow?
It shouldn't be, despite the circuitry at its heart its just a physical connector.  RS232 sends data in a serial manner with a ground and signal line into the transponder,  USB is Universal Serial Bus, 4 connectors, +5v, 0v, signal and signal ground.
There's no decoding/rewriting of the data packets being done, its at the signal layer.
Worth checking that the baud, error correction bit etc are set the same and match the Funke and PAW,   and maybe there's a problem with one device not being able to keep up so a different baud rate might help, but 9600 isn't exactly fast.
Geoffrey

5
I've not used the GPS Global exchange before but just had a play with it interrogating my flight last eve and I do indeed appear to be going backwards and sideways.

I then looked at my flight on FR24 and I was always going forwards, as I was when I checked the flight at the time.

I then looked at G-CIJO's flight on Flight radar from 2/5 and it was always going forwards. It looks like something to do with the functionality of the GPS Global exchange's presentation of the flight data. That doesn't show what's being presented during live flight of course but as I understand it any system will join up individual position reports and string them together so it's where you are each time your transponder transmits.
...
I've been flying with G-CIJO and have seen first hand on my pilot aware the incorrect funke transponder direction information showing his plane always pointing North rather than correctly showing the plane orientation.   It's not constant though, sometimes his plane points in the right flight direction, sometimes it points North.   I've taken screen shots of the issue for Brian to send to Funke.    We've put this 'flipping' of direction to sometimes my PAW is picking up his transponder signal and sometimes it picks up his pilotaware signal,  PAW correctly sends the direction track and so when receiving PAW signal the plane tracks in the right direction,  when receiving the transponder it points North.

And we think this is the cause of the discrepancy between adsb exchange (which as it says is displaying ADSB information) and flight radar 24.  FR24 says that it gets its track information from ADSB receivers AND glidernet (which is linked to the Atom grid network to receive PAW signals)  We think its is prioritising the glidernet traffic displays over the ADSB, hence why FR24 shows the right orientation but ADSB exchange doesn't.

You make a good point that the flight replay websites could be interpreting the flight information and determining their own orientation information, not displaying what is actually received.  We can't know for sure whether that is the case or not, but I can say with absolute confidence that Brian's PAW/Funke transponder combo will sometimes show the plane on the right track and sometimes it pointing North.  The North orientation usually appears when we are further apart in flight and when we're not in the locality of a PAW ground station - further strengthening our view that its the transponder at fault.

Geoffrey

6
Technical Support / Re: Missing Vector Plot
« on: April 20, 2021, 09:33:58 pm »
Hi Brooklands

Are you looking for the PAW data or CAP1391 ?
I also see the last time you were reported was 31/March
which systems were active on the 4/April ?
We did have a break in data recording from around 11AM of the 4th/April

Thx
Lee
Was the break in recording for most of the day Lee?

i flew on 4th April at 18:40-19:30 BST and there was no ADSB or PAW capture on Vector.  Other days captured fine, so I assumed something wrong at 'base' as it was strange there were nothing and ADSB exchange captured me ok.

(my hex code is 405f7f)

Cheers, Geoffrey

7
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: April 01, 2021, 09:39:41 pm »
I think I know the source of the original problem which was fitment of the BNC cable onto the existing antennae cable,  the outer shield was crimped onto the outer rubber sleeving and not the wire braid inside, so when the BNC was plugged in it could push the pin backwards partly out of the plug and cause it to short on the outer shielding.
Although I could re-make this one to be more secure I've made up a whole new cable and thoroughly tested it for continuity in the right and wrong places.   Its waiting in the car boot to take it and fit back to my plane.
...
Cheers, Geoffrey
First flight today after lockdown, unfortunately I missed the good weather as I was away earlier in the week, so it was decidedly lively for my check flight today.

To try to isolate the cause of the front RHS blind spot on PAW I tried flying without the Anker plugged into the USB socket by the front strut.

Looking at the Vector diagrams after what was a very local 30 minute flight it does seem to still have the front right gap, so suggesting its the front strut rather than the Anker.  Most traces from 10km away but encouragingly some traces up to 40km.  When I get the chance for longer flights I'll see if this bears out.

And I now have ADS-B working now and appearing on Vector as well,  and on https://globe.adsbexchange.com/?icao=405f7f&lat=52.148&lon=-0.311&zoom=12.9&showTrace=2021-04-01 the trace is absolutely rock solid, no gaps or faint lines at all, so the new Transponder to Antenna cable did the trick.

Cheers, Geoffrey

8
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: January 13, 2021, 08:55:08 am »
...
This morning I thought to test the continuity of the inside pin to the shielding,  and I can report that that's showing great continuity as well, barely any resistance at all !

Think I now know the source of the ADSB transmission quality.  I'm sure i was careful to not get any braiding trapped when I shortened the cable, but clearly I must have done somehow.   Will see if I can find and fix it, otherwise will continue with plan A of making up a new cable.

Thanks for all your help and advice

Geoffrey

Hi Geoffrey,

I had a long chat on the phone to one of my contacts in Trig Technical Support this afternoon. She confirmed that the output of the TT21 is protected, so hopefully all will be well once you fit your new cable.

Best Regards

Peter
Thanks Peter, that's useful to know.  Good old Trig.

I think I know the source of the original problem which was fitment of the BNC cable onto the existing antennae cable,  the outer shield was crimped onto the outer rubber sleeving and not the wire braid inside, so when the BNC was plugged in it could push the pin backwards partly out of the plug and cause it to short on the outer shielding.
Although I could re-make this one to be more secure I've made up a whole new cable and thoroughly tested it for continuity in the right and wrong places.   Its waiting in the car boot to take it and fit back to my plane.

Miserable foggy weather today so not like I'm missing anything,  but yesterday was clear and I heard the sonic boom from the Typhoon jet from Coningsby as it rushed to intercept an errant German pilot that had lost comms.  We should check their Vector plot !

Cheers, Geoffrey

9
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: January 07, 2021, 01:49:44 pm »
Quote
This morning I thought to test the continuity of the inside pin to the shielding,  and I can report that that's showing great continuity as well, barely any resistance at all !

Yikes!
I hope that has not damaged the power output amplifiers by shorting, might be worth consulting the manufacturer

On a related note, I am happy that the VECTOR service helped identify the issue - even if that is not its main intention!

Thx
Lee
It did indeed thanks Lee, I would probably have been none the wiser on this issue other than perhaps some ATC's reporting poor visibility of my transponder.

Peter's useful guide to checking the PAW to Transponder connection,  and then mine to check the continuity (or not) of the cable might be worth writing up somewhere.

I'll makeup a new cable and will have to wait until can fly to try it out.   Don't think at the moment I can make provision for this as urgent flight safety,  maybe when lockdown starts easing.

Thanks again all

Geoffrey

10
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: January 07, 2021, 01:16:29 pm »
Thanks Peter for your advice on checking the transponder and Pilotaware connection.

Went briefly to the airfield yesterday evening,  the transponder head is showing the GPS coordinates from PilotAware when you press FN several times, as I thought it was.

I have removed the transponder body to antennae cable and took it home with the plan to make up a new cable with the plugs I've ordered.  Testing it last night, it appears to have good continuity both on the outside shielding and the inside pin, so thought it might be due to degradation of the shielding over time that was causing the poor transmission quality.

This morning I thought to test the continuity of the inside pin to the shielding,  and I can report that that's showing great continuity as well, barely any resistance at all !

Think I now know the source of the ADSB transmission quality.  I'm sure i was careful to not get any braiding trapped when I shortened the cable, but clearly I must have done somehow.   Will see if I can find and fix it, otherwise will continue with plan A of making up a new cable.

Thanks for all your help and advice

Geoffrey

11
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: January 05, 2021, 03:09:01 pm »
That front strut is too close to the PAW antenna. I suspect it may be acting as a reflector and improving the signal to the left at the expense of the right.

Many microloghts and Gyros have the coms antenna on the top of the nose, as far forward as possible. Is that an option?

I was about to suggest moving your existing antenna to just inside the outer edge of the upper windscreen - as high up as you can manage, which would clear the immediate (close) obstructions, and help to reduce obstruction to the right rear due to Pilot, Passenger, Pylon and Engine, etc., but have just seen your recent post about dropping the wing for storage, which would make this awkward (though not impossible - it would just involve disconnecting the cable from the antenna before removing the upper screen).

...
WRT your ADSB issues, it definitely looks like a fault to me. Loss of GPS to the Txpdr - would prevent Mode-S/ES transmission, but would also affect PAW transmissions and would be reported as gaps on your Nav System and PilotAware Tracks, so relatively easy to check. Please let us know how you get on.
 

Best Regards

Peter
An update on my PAW and ADSB results from the flight I managed to get in on 2nd January,  probably the last for a while  >:(

I moved the PAW ADSB antennae up as high as I could on the lower windscreen,  so it was half on the bottom windscreen and half on the upper.   PAW Vector was near identical to prior flights.  Having looked at Brian Montilla's trace, his trace doesn't show the right hand 'blind spot' mine does, but his Rosetta is mounted underneath the lower windscreen so has antennae in almost identical position to mine.   This makes me think that its not the front strut that is shielding the signal,  I am wondering whether it is the USB cigarette socket converter for my ipad which is on the opposite side of the front strut from the PAW antennae.
I'll try flights with no power converter plugged in or a different one in use,  somehow I have misplaced the Ankher I was using.

ADSB, no positive progress.  Moved the GPS mouse to above the coaming and didn't see any GPS dropouts on my Trig or Skydemon in flight.   The Vector plot is non existent again, and looking at Flightradar 24 and ADSB Exchange, they both show a patchy flight trace.
Have ordered replacement plug to makeup a new antennae cable for my transponder as first option before I change the transponder antennae.

But next stage of testing these will depend on ability to fly again :-(

Geoffrey

12
General Discussion / Re: VECTOR analysis and obscuration video's
« on: December 31, 2020, 12:43:43 pm »
Here's the link to the PilotAware YouTube channel https://www.youtube.com/c/PilotAware

and to the most recent videos:
Electronic Conspicuity and Obscuration https://www.youtube.com/watch?v=Xu8a0f0PkzY
Vector Electronic Conspicuity checker https://www.youtube.com/watch?v=VOoZPhzFNDY

13
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: December 31, 2020, 12:40:06 pm »
Hello GeoffreyC,

I'm not so sure Flight Radar is tracking you very well.
There is a big section between  Clapham and Sharnbrook where there were no tracking points.

Oundle to Peterborough looks good, but 'jumpy' between Whittlesey and Gold hill and also jumpy in the St Neots area.
Note: there are approximately 3,000 Flight radar ground stations compared to approx 200 ATOM stations so the chances that FR24 picks up your ADSB transmission is much higher because you are likely never to be far away from an FR24 station.
Flight on the 22nd shows similar big jumps.
However, flights in July show a good signal being picked up, so has a connector been disturbed or something else changed?

I'd be looking at the ADSB antenna / cabling installation, FR24 (and Vector) are indicating a possible range problem.

Deker.
Thanks Deker.

The transponder cable did get shortened and a new plug fitted on it post accident as the old cable was always too long (bent around the pod bag) and in fact it came off when I was dismantling the plane.  I am sure I checked there were no shorts when I put the new plug on it, but I'll check again.

Suspect some of the jumpiness on the FR24 track is the PAW GPS losing signal.   The GPS mouse trail prior to July was on the top of the pod, to the right of the front strut.  Post-accident reassembly it got installed on top of the base tube at the bottom of the front strut.  On the flight of the 22nd I noticed a couple of GPS dropouts and planned to relocate the GPS mouse,  so I'll do that first.    It doesn't explain a potentially poor range on ADS-B though.

Geoffrey

14
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: December 31, 2020, 12:31:31 pm »
That front strut is too close to the PAW antenna. I suspect it may be acting as a reflector and improving the signal to the left at the expense of the right.

Many microlights and Gyros have the comms antenna on the top of the nose, as far forward as possible. Is that an option?
Thanks Ian, I suspected that the front strut was causing problems to the right and Vector certainly shows it up in a very visible way.  Hadn't thought that the strut might be improving the left side as well as impacting the right.

Putting the antenna on the front of the nosecone is an option,  my pod had its radio antenna originally there and I know that Brian Montilla has his PAW one mounted on the front in the hole.   Following my accident I had a new pod made by Albatross (and they've done a good job of the fabrication), so would have to be drilling a hole in the virgin fibreglass  :(

Its not a position I favour because we store our trikes with the wings de-rigged and so have to drop the base bar over the nose of the trike every time we put the plane away and vice-versa to re-rig it.  I've caught the antenna with the bar on a previous trike and ripped the fibreglass as a result, so would prefer not to introduce that risk.

Having said that, it does make logical sense that this would maximise my front visibility, doubtless at some impact to rearwards.

Will look at Brian's traces and see how his PAW visibility compares to mine.

15
Technical Support / Re: Vector shows PAW but not ADS-B signals
« on: December 30, 2020, 07:20:22 pm »
(continued)

What was surprising was that Vector reports NO ADS-B traffic at all.

My transponder was on, it was connected to PAW and was receiving a GPS signal,  and flightradar 24 shows my flight pretty much from when I left the circuit to when I returned back.   FR24 is using ADS-B to trace my route so I am confused

Geoffrey

Update:  the runway had dried out enough today to get up in the air again,  this time a much longer 2 hour flight around Bedford, Peterborough and towards Ely.

Looking on Vector, same/similar results.

A good set of PilotAware traces, 5676 contacts today, up to 60km away, and definite issue on front/right, caused I think by the front strut.  I could move the antennae in front of the strut but then I fear I'd get no rearwards signal,  I could mount it under the pod further back, but then great for planes below me, but what about above?

ADS-B does show 35 contacts, all very close range,  and again FlightRadar tracks me fine, screenshot of the latter half of the flight below.

And, another strange thing, Vector is showing 869 pilotaware contacts from 9th August.  They weren't there last week, I didn't fly then and in fact the plane was dismantled and PAW stripped out of it then,  so unless someone else was inadvertently using my ICAO hex code, these don't make sense.

Pages: [1] 2 3 ... 8