PilotAware

British Forum => General Discussion => Topic started by: Mike Mold on April 19, 2021, 10:43:21 am

Title: External antennae on Jodels
Post by: Mike Mold on April 19, 2021, 10:43:21 am
Have any Jodel owners installed external antennae for their PAW kit? I've used my Rosetta on the rear shelf of my D117 and using Vector I've found that the forward looking 30 degrees arc is poor on signal strength due, I'm presuming, to the mass of engine and water (me) in the way. Hence, I'm thinking of fitting external antennae and the logical place to install them is on the lower fuselage behind the trailing edge of the wing, next to the access panel where my xpdr antenna is located. I know that I shouldn't fit the 1090 MHz antenna close to my xpdr antennae but any thoughts would be appreciated. 
Mike (D117A G-BFEH)
Title: Re: External antennae on Jodels
Post by: MartC on June 30, 2021, 06:23:50 pm
Yes - we mounted ours on the aluminium rear fuselage access panel - our transponder antenna on one side, the PAW in/out and ADSB receiver on the other side, spaced apart. Seems to work fine.
Title: Re: External antennae on Jodels
Post by: Mike Mold on July 02, 2021, 07:46:56 am
I've now done the same with better results from Vector.
Title: Re: External antennae on Jodels
Post by: exfirepro on July 02, 2021, 08:20:36 pm
Mike / Mart,

Well done both - external antennas are almost always a significant improvement, even in flexwings!

It would be really helpful if one (or both) of you fancy writing up brief details of your permanent Jodel fit (with photos / before and after Vector screenshots and any other significant hints or tips) and posting it in the ‘Fixed Installations’ section of the Forum (see previous posts there for examples). That would make it much easier for us to direct other Jodel owners to the details in future.

Best Regards
Peter
(PilotAware Development)
Title: Re: External antennae on Jodels
Post by: Ian Melville on July 02, 2021, 09:15:00 pm
Is there not a danger that we will install antenna to get the best reception in Vector, a ground station analysis, when we should be looking at Air-Air performance first?
Title: Re: External antennae on Jodels
Post by: PaulSS on July 02, 2021, 10:46:08 pm
Quote
Is there not a danger that we will install antenna to get the best reception in Vector, a ground station analysis, when we should be looking at Air-Air performance first?

Are the two mutually exclusive? Surely good Vector/ground station analysis = good antenna placement = better air to air than not having good vector/ground station performance.
Title: Re: External antennae on Jodels
Post by: Ian Melville on July 02, 2021, 10:52:26 pm
No they are not. Fit antenna under a metal aircraft and the signal will be blocked above the wing.
Title: Re: External antennae on Jodels
Post by: exfirepro on July 02, 2021, 11:17:24 pm
Ian/Paul,

Whilst that is technically ‘correct’, all the tests we have carried out indicate that it is almost impossible for an inbound aircraft to get to a position where it is ‘obstructed’ directly above or below the PilotAware equipped aircraft without being picked up from further out during the approach.

In any event, external antennas invariably prove more effective overall than internal ones - especially (but not exclusively) in metal-bodied aircraft.

Best Regards

Peter
Title: Re: External antennae on Jodels
Post by: Ian Melville on July 03, 2021, 07:11:49 am
Peter,
I totally agree regarding having the antenna external.
You may find that at a distance, you can see a target, but I don't think you are likely to have a mid air with those ones :o. But it will still be partially obstructed if metal or water is placed between the two aircraft. I have seen a PA28 with 1090ES disappear from my PAW as it banked towards me (presenting top of wing to me), and reappear once wings level. I was on the ground and PA28 turned final, no risk in this case, but a good demo of why antenna diversity is a good idea. There is no perfect position for a single antenna, which can only be placed to offer protection in the most likely scenario.
Title: Re: External antennae on Jodels
Post by: MartC on July 03, 2021, 10:31:39 am
Mike / Mart,

Well done both - external antennas are almost always a significant improvement, even in flexwings!

It would be really helpful if one (or both) of you fancy writing up brief details of your permanent Jodel fit (with photos / before and after Vector screenshots and any other significant hints or tips) and posting it in the ‘Fixed Installations’ section of the Forum (see previous posts there for examples). That would make it much easier for us to direct other Jodel owners to the details in future.

Best Regards
Peter
(PilotAware Development)

Hi Peter, our install was fitted in the Jodel just before first lockdown spring 2020 and we have had little opportunity to flight test, coupled with a protracted engine rebuild this spring which has prolonged our getting back into the air until only recently. Currently running in the new engine (and refreshing pilot currency) and may be little time before we can fully understand and configure our PAW system. Recent flights (after 6 months on the ground) we seem to have had a problem with the licence renewal not updating on the device, so nothing showing on vector for our Hex ID, need to recheck the settings (we have paid this year !!). Otherwise, once we know its all working, will look at sorting out a write up and take some photographs.

Regards
Martin
Title: Re: External antennae on Jodels
Post by: exfirepro on July 03, 2021, 03:41:44 pm
Hi Martin,

Thanks for the reply and I appreciate the ongoing issues. It would be great to see a ‘Jodel Fit’ fixed installation option (or options) added to the Forum in due course for the benefit of other Jodel Owners.

With regard to the problem with the licence renewal key not updating on the device, this could be linked to the software version on the device. IIRC if this is one of the older software versions the new licence key will not be recognised. In this case you should first update the software to one of the more recent (2020xxxx) versions. Any problems please come back to me.

Regards

Peter
Title: Re: External antennae on Jodels
Post by: MartC on July 03, 2021, 05:40:00 pm
Thanks for the advice. Its a Rosetta and according to the update app on my phone, current version is 20201101 licence expires 2-May-2022. We have had around 4-5 flights over the past week or so, nothing showing on vector. I think the first couple of flights might have coincided with expiry failure, oddly Skydemon worked perfectly first flight then would not connect second flight, checked through the iPad the pilotaware admin page 192.168.1.1 on the wifi connection whilst still in the aircraft and clicked the 'update software' button, then it seemed to work with in flight navigation normally again. We didn't turn the unit on for the subsequent flights, busy with other snagging. Subsequent check of vector website shows no flights, so I am wondering if the Hex ID has dropped off the settings somehow..... can't check until next back at the aircraft, that's the only problem with a permanent install, the unit is not removable to play with at home. It would be good if the phone app could 'save' the last on-device settings page so that you could see what the Rosetta setup is without being connected 'live' and /or whether it was broadcasting correctly.
Title: Re: External antennae on Jodels
Post by: exfirepro on July 03, 2021, 10:19:35 pm
Original Post Edited Sunday 8am

Hi Again Martin,

From what you say above, it looks like the Licence Key has now been accepted (which it certainly should have been with 20201101). It sometimes requires a shut down and reboot of the device for the new licence date to show - which is probably what has happened here. Pressing the ‘Update Software’ button when your iPad was connected to your Rosetta would have no effect unless a software update had previously been downloaded but not installed.

The ‘No show’ on Vector seems a bit strange, however, if you had the unit running, though it seems there was some confusion as to whether and when the unit was working. When and where were you flying? If you can post (or message me) your HexID/Reg, I will take a look on the PAW database and see what is going on and will let you know what I find.

I will pass your suggestions re the Firmware Updater App on to Neil (the Developer). In the meantime it’s quite simple to take a set of screenshots of the main Home, Configure, etc Screens on your iPad when it’s connected to your PAW. I always try to remember to do this whenever I make any changes to my settings (or when I’m setting up a unit for anyone else) as it acts as a very valuable reminder - and can be posted on here to assist with remote diagnosis.

Best Regards

Peter
Title: Re: External antennae on Jodels
Post by: MartC on July 04, 2021, 10:35:06 am
Very helpful thanks Peter. Hex 401E9B G-BHVF vicinity of Henstridge - Yeovilton. 23 June 2021 1145-1600 (subsequent flights not sure if PAW activated as we were looking at other aspects, although it was plugged in so should have been transmitting). Our PAW is connected to transponder for ADSB-out.
Title: Re: External antennae on Jodels
Post by: steveu on July 04, 2021, 12:05:37 pm
Very helpful thanks Peter. Hex 401E9B G-BHVF vicinity of Henstridge - Yeovilton. 23 June 2021 1145-1600 (subsequent flights not sure if PAW activated as we were looking at other aspects, although it was plugged in so should have been transmitting). Our PAW is connected to transponder for ADSB-out.

If the PAW was on and had GPS lock it will have recorded a .trk file for the days in question, connect your device to the PAW Wifi, download the .trk file(s) then upload then to Aircrew, replay the flight and see which ground stations the PAW connected to in the flight and the distances involved.
Title: Re: External antennae on Jodels
Post by: Admin on July 04, 2021, 02:11:59 pm
@martc
are you sure you have the correct hex code programmed into your PAW ?
I can find no record of this ICAO since November 2020

I have a suspicion the hex code is set to the default for your unit F384E8
I saw this flying 30/June
if so - this has stunning PilotAware coverage

Thx
Lee
Title: Re: External antennae on Jodels
Post by: MartC on July 04, 2021, 05:17:02 pm
Hi Lee, this might be the case, would explain why our navigation was working (Skydemon off the PAW GPS), but I cannot find the vector on our correct Hex ID. The aircraft has been grounded since November due to lockdown /engine rebuild complications, only flying for the first time on 23 June. Until I can get back to the aircraft I can't check, but it would explain if the Hex has reset to default for some reason. I wonder if the settings were inadvertently changed due to the licence software update complication we had. Will report back asap. Regards Martin
Title: Re: External antennae on Jodels
Post by: exfirepro on July 04, 2021, 10:56:18 pm
Hi Mart,

Sorry I got distracted earlier and didn’t get back to the Forum - rain coming in through my Utility Room roof again in today’s thunderstorms, but I see Lee has responded to your HexID post.

As Lee says, there is certainly nothing on the database from 401E9B - neither from PilotAware OR ADSB, which suggests that you may have inadvertently activated the default profile when trying to ‘Save’  the new licence key. The ‘Profile’ select button is right next to the ‘Save’ button at the bottom of the ‘Configure’ screen, and if the profile with the default F384EB Hex has been inadvertently selected (which seems likely as the PAW is clearly transmitting on F348EB), that profile probably won’t contain the correct USB Port settings to supply the GPS data to the transponder for ADSB out - hence no ADSB reports on the PAW database from 401E9B either - which is definitely the case.

Easiest fix would be to reselect the ‘Correct’ Profile - with the correct USB Transponder Port Settings, (check the rest of the settings while you are in there and re-save if you change any), then go back later and delete any unwanted profiles - remembering to reselect the correct one before exiting.

FTAOD, SkyDemon would still get the GPS data, whatever the HexID was set to, so would still work as normal.

Best Regards

Peter

Title: Re: External antennae on Jodels
Post by: Mike Mold on July 06, 2021, 09:56:51 am
Hi Peter, the description of my Jodel antennae mod is now in the Fixed Installation thread area.
Regards, Mike
Jodel D117A G-BFEH
Title: Re: External antennae on Jodels
Post by: exfirepro on July 06, 2021, 01:10:51 pm
Well Done Mike!

That will be very useful for anyone running PilotAware in a Jodel (or similar) aircraft. The ‘before’ and ‘after’ Vector screenshots clearly show the benefit of getting the antennas outside and your photos complement the written description perfectly.

Thank you

Best Regards

Peter
Title: Re: External antennae on Jodels
Post by: MartC on July 06, 2021, 01:59:55 pm
@martc

I have a suspicion the hex code is set to the default for your unit F384E8
I saw this flying 30/June
if so - this has stunning PilotAware coverage

Thx
Lee

Lee, PAW range approaching 80km on 23 June was at 4000ft. Shorter range produced on 30 June at 1200ft or so, but still a respectable 40km..... vector shows a reasonably even 360 spread suggests a very good result from our external antenna position.
Title: Re: External antennae on Jodels
Post by: MartC on July 15, 2021, 03:52:23 pm
Hi Mart,

As Lee says, there is certainly nothing on the database from 401E9B - neither from PilotAware OR ADSB, which suggests that you may have inadvertently activated the default profile when trying to ‘Save’  the new licence key. The ‘Profile’ select button is right next to the ‘Save’ button at the bottom of the ‘Configure’ screen, and if the profile with the default F384EB Hex has been inadvertently selected (which seems likely as the PAW is clearly transmitting on F348EB), that profile probably won’t contain the correct USB Port settings to supply the GPS data to the transponder for ADSB out - hence no ADSB reports on the PAW database from 401E9B either - which is definitely the case.

Easiest fix would be to reselect the ‘Correct’ Profile - with the correct USB Transponder Port Settings, (check the rest of the settings while you are in there and re-save if you change any), then go back later and delete any unwanted profiles - remembering to reselect the correct one before exiting.

FTAOD, SkyDemon would still get the GPS data, whatever the HexID was set to, so would still work as normal.

Best Regards

Peter

Hi again Peter, now attended to the Pilotaware configuration, selected the correct Hex ID profile and deleted the default, so settings are now as here:

From the vector, we are now getting Pilotaware broadcast correctly, but nothing for ADS-B out, although the settings show the Funke transponder in Port 2. Any reason why the ground network should not see our ADS-B - for example, do the stations local to EGHS (Henstridge) not have that capability? We actually flew (14/7/21) a circular route around Yeovilton, Henstridge-Seaton-Taunton-Wells_Henstridge.

Flight Radar 24 has this for the flight, not sure if that is our Mode S track....
https://www.flightradar24.com/data/aircraft/g-bhvf#2866392e

ADS-B Exchange has this:
https://globe.adsbexchange.com/?icao=401e9b&lat=51.069&lon=-2.057&zoom=9.0&showTrace=2021-07-14

Suggests we are broadcasting ADS-B but vector not seeing that, or am I not understanding the websites quoted....?
Title: Re: External antennae on Jodels
Post by: MartC on July 15, 2021, 03:54:47 pm
Here is the ADS-B trace from vector:
Title: Re: External antennae on Jodels
Post by: MartC on July 15, 2021, 04:27:12 pm
Here is our settings configuration page:
Title: Re: External antennae on Jodels
Post by: exfirepro on July 21, 2021, 09:09:06 pm
Hi Martin,

A whole new can of worms opened up when you mentioned a Funke Transponder. Unfortunately I can't get the FR24 track to play, but the adsbexchange trace clearly shows your aircraft constantly oriented Northwards - irrespective of the fact that it was presumably heading straight along the track, - which is a clear indicator that the transponder isn't transmitting the correct data.

Lee has already done a considerable amount of investigation into this phenomenon, which has identified a discrepancy between the format of the data passed to the transponder by PAW and the format which Funke Transponders expect to receive. As a result He has produced a beta version of the PAW software specifically designed to address this issue (though in my opinion, the problem still lies with Funke - NOT PilotAware). This beta software has been tested successfully by at least one other Funke User to my knowledge and I'm sure Lee might like you to give it a try to see if it resolves the problem with your unit.

It would ,however, first be useful to know exactly which model of Funke Transponder you have and what firmware version it is running. Also has it been back to Funke for updating to ensure that it will broadcast ADSB - (Not all work even after 'modification). I would also like you to check that your USB to RS232 cable is in fact in Port 2 (lower left when looking at the USB Port end of the PAW with the ethernet port on the left). We would also need to check the recommended Baud Rate for Funke (I know Trig now recommend a minimum of 9,600Baud).

You can find lots more info about this phenomenon by searching for 'Funke Transponder' from the Forum Home Page.

Best Regards
Peter
Title: Re: External antennae on Jodels
Post by: MartC on July 22, 2021, 09:25:11 am
Peter, many thanks once again for all your input to this.

Ours is in fact the more recent Funke transponder model TRT800A OLED installed in 2015 by a professional avionics engineer with firmware update 5.3. It does not suffer from some of the problems which beset the earlier models /software, but it does not surprise me that it may not output the correct speed /direction vectors. Although, according to the information on extended squitter operation (ADS-B) published by Funke: "Airborne position and airborne velocity are sent out if reliable data is available"

At the time (February 2020) of our connection by the same avionics engineer of an uncertified GPS (Pilotaware Rosetta) to enable ADS-B out, SIL value on the Funke transponder was set “0” (as per recent LAA approval) and tests carried out satisfactorily confirming ADS-B out working. Although the FR24 trace may not verify as this could be our Mode S transmission I imagine, the ADSBexchange trace I assume is based on an ADS-B signal for our aircraft, albeit not with correct velocity shown (constant pointing north).

Pretty sure the Farnell USB cable is in USB2 slot but will check tomorrow at the aircraft. Also, baud set for 4800 which matches the Funke, again will check this.

We would be happy to trial the beta software and report back. I assume that modifies the GPS information sent by Rosetta to the transponder to 'force' the correct speed/velocity out data?

PS - we wish we'd bought a Trig ! ::)
Title: Re: External antennae on Jodels
Post by: exfirepro on July 22, 2021, 10:05:11 am
Hi Martin,

Thanks for the update. Don't know whether Lee want's to publicise what he found with the Funke, but yes - basically a question of a 'missing' decimal point - which AFAWK only 'Funke' seems to need.

I'm sure Lee will be happy to give you access to the beta version to try - it certainly fixed the issue for Brian Montilla.

I have PM'd Lee.

BR
Peter
Title: Re: External antennae on Jodels
Post by: MartC on July 23, 2021, 03:44:28 pm

I would also like you to check that your USB to RS232 cable is in fact in Port 2 (lower left when looking at the USB Port end of the PAW with the ethernet port on the left). We would also need to check the recommended Baud Rate for Funke (I know Trig now recommend a minimum of 9,600Baud).

Best Regards
Peter

Photo attached of Rosetta connections, shows Farnell in USB2, GPS in USB1. Baud rate is 4800 for the Funke, discussed with our avionics guy who thinks it would make no difference re-setting to 9600, although I think the Funke can be set to the higher rate.