[The Westmorland Flyer]

I'm chasing this down as well, as I'm seriously thinking about putting a KT74 in my Sportcruiser.

Mendelssohn told me today that the current KT74 has the Trig 3.4 firmware, which does support ADS-B out with SIL=SDA=0, as required. Whether that applies to older models of KT74 is unknown, so for a start I suggest checking the firmware revision level. I am still trying to get to grips with the relationship between the TT31 and KT74. The latter must have some additional/different firmware to support the number buttons but beyond that all the evidence I have so far is that it is a TT31 in disguise.

Next is the GPS capability. As I understand it, ADS-B out only works if your GPS supports (and is receiving) EGNOS WAAS satellites.

I think this trial, with its distinctly odd parameter requirements, has put the cat amongst the pigeons, with transponder manufacturers scrambling to keep up (or not) and rather a lot of misinformation out there.

[ianfallon]

It does sound like PilotAware is the affordable option for you to do this Rob plus you get ADS-B in on your Nexus tablet software (SD ?) plus the PilotAware peer-peer system as a bonus

[Rob P]

Ummm... OK



It must be hard for those who understand the complexities of the current electronics conspicuity to know just how baffling it is to those who don't

Rob P

[PaulB]

I haven't set up pilot aware, but I have just set up a standard raspberry pi by following the instructions on how to do so..... I can't tell the difference between an Ohm and a Watt and a Volt(a).

Provided I can get to Yorkshire, Pilot Aware is tomorrow's project!

[FASVIGcoord]

......with transponder manufacturers scrambling to keep up (or not) and rather a lot of misinformation out there.

Indeed. Hence my push to try to get minimum requirements statements from as many transponder manufacturers as possible and post them on the FASVIG website.

It started with Trig because I had information from one Trig owner about his unsuitable firmware level and being advised to upgrade. And Trig came through to me with the info. I have now emailed five other manufacturers pointing them at the FASVIG web page containing the Trig info and asking them for similar. Air Avionics (Garrecht) responded very positively the next morning saying they will create and send me a guide. I am awaiting responses from the others. I did not email Garmin as they refused to engage with NATS on their uncertified GPS trial so I saw no point.

What ADS-B seeks to achieve - basically broadcast of an aircraft's GPS position - is simple in principle. Unfortunately, the definition and workings of the ADS-B specification is very complex. It also leaves scope for manufacturer's to take different approaches to how they implement it. E.g. Some may provide a way to set the ADS-B Operational Status Messages to the values that the CAA have demanded for use with an uncertified GPS, while others may not. Of course this situation can change if a manufacturer chooses to make it change - it is likely just a change to the firmware to bring that about. (I appreciate even this may be a pain for some owners as upgrading firmware means de-installing the transponder and sending it somewhere to be upgraded and maybe paying a sum of money for the service!)

My hope is that by publicising those makes of transponders that do a good job of supporting uncertified GPS it will provide a bit of a prompt to those that do not. I have also pressed the point with the CAA that they need to do more on getting better support out of the transponder manufacturers. That means transponders that work with uncertified GPS and much better provision of information, including in their manuals, about what is needed and how to get it working.

[Rob P]

That means transponders that work with uncertified GPS ..

Am I correct in my assumption that the above should now read "uncertified WAAS GPS"?

Rob P

[Paul_Sengupta]

That means transponders that work with uncertified GPS ..

Am I correct in my assumption that the above should now read "uncertified WAAS GPS"?

I don't think there's any reason it should apart from maybe some manufacturers implementing it that way in their software.

Apparently the Trig works fine with the PAW output which is non-WAAS tagged.

Garmin seem to specify that their transponder will only work with a WAAS GPS though - or at least will only be certified with one.

[FASVIGcoord]

Hi Rob,

No, that would not be my view. Uncertified is uncertified. Of course, the CAA may have a different view. As Westmorland said, the focus of ADS-B has been heavy, heavy certified kit and this move to uncertified GPS is exposing differences of opinion in how to do that within the ADS-B spec.

For example, on the Trig transponders the ADSB Op Status Message settings for use with an uncertified GPS are driven simply by the user declaring "Uncertified GPS" in the setup menu and feeding NMEA0183 data, of which only one particular sentence matters, into the transponder. So, as far as I know, the Trig implementation cares not about WAAS.

Steve

[FASVIGcoord]

?.... and this move to uncertified GPS is exposing differences of opinion in how to do that within the ADS-B spec.

And not just 'how to' but 'whether to'!

[Paul_Sengupta]

Apparently the Trig works fine with the PAW output which is non-WAAS tagged.

tWF has done some trials with the PAW and the UBlox USB GPS (£6 or less), and when it's receiving the EGNOS satellite, it *does* output that it's DGPS active. So, this may solve your problem Rob, if indeed this is what the transponder is looking for.

[Rob P]

Is this going to make any difference?

Raspberry Pi Foundation: UK Nonprofit Unveils New Basic Computer Device, Pi Zero

The Pi Zero's motherboard includes USB and Wi-Fi capabilities and is the size of a money clip. Available Thursday for $5, it's the cheapest Raspberry Pi device ever, The Wall Street Journal reported.

Rob P

[Paul_Sengupta]

I was looking at that on the Farnell website earlier. I think for the moment no, but it might become the basis of some sort of industrialised PilotAware in the future.

[morticiaskeeper]

I've got one!

With another on the way tomorrow. It's very small, and very nice!

One will control the fish tank, the other will just be used as a hack base.

The lack of USB sockets may be a bit of a problem for PAW use. By the time you've got an adaptor and USB hub fitted, it would probably be bigger than a B+.