Gaznav

@RFguy - have you got any results yet from this? I’d be interested to know if you have any idea of the radiation patterns of those PCB antenna. Cheers, Gaz

Thanks Kyle - I didn’t know that. FLARM is standardised around Europe, so I naturally assumed it was the same globally. Another reason to adopt ADS-B then 👍

SkyEcho 2 receives FLARM too, but you need something like Fore Flight or Sky Demon with a FLARM licence (costs $30-$40 per year) to decode the signal. This is SkyDemon decoding FLARM from my SkyEcho. You can see a glider on final and a glider/tug with individual FLARMs fitted. Maximum range of FLARM detection is about 5nm - it’s a pretty weak signal. The other problem with bearing less Mode S and Mode C detection is that the proximity is worked out on signal strength. Power outputs from transponders range from 70W to 500W. So if your kit detects a 500W transponder it will warn you and make you think it is much closer than it actually is - or vice versa, it will not warn you as it thinks the weaker signal is further away. That is, I understand, why uAvionix ceased their development of the Mode S and Mode C bearing less detection - it is too unreliable. 👍

Cheers Graham, Merry Christmas to you all too. 🎄🎅👍🍻 There is also a few articles on this in the latest UK Flyer mag - free to view here: https://www.flyer.co.uk/electronic-conspicuity-devices-tested/ (link towards the bottom of the blog). I don’t work for Flyer either.

Hi Kyle, no they receive the ADS-B tracks (with their GPS) positions, and with the ground station position, they crunch the numbers of range and angle. It’s known as Pilot Aware VECTOR and it’s a free system they are offering people in the UK to check the ranges of their ADS-B, FLARM or P3i (which is a proprietary signal from Pilot Aware devices) installations. It’s a pretty neat system, but it does have a draw back - in that the ground station receivers aren’t a set standard (so they could have 3dB, 5dB, 7dB or even high end 9dB antennae) and it will only report the ranges that you fly from those receivers (so if you only fly 10 miles from a ground station, it will only report 10 miles). So the polar diagram can be very deceptive as it is not showing received strength like a normal diagram, but only the data that has been received - it’s good for the ‘knowns’, but not so good for the ‘unknowns’, if you get what I mean? Here is a link to their ATOM station - as you can see it is basic Raspberry Pi, SDR and an 1090 MHz antenna: https://global-uploads.webflow.com/5d56c24810fbfdbe08b488cd/5fbfd1a1de7eec471fcb156d_LATEST ATOM GRID installation December 2020.pdf It’s clever stuff, it is a really benevolent gesture from Pilot Aware, but you have to think carefully about what it is actually showing you. This is a link to their ATOM VECTOR explanation: https://www.pilotaware.com/analysis/vector Best, Gaz

PS. I should add that I don’t work for uAvionix. I am a WG CDR Fast Jet Weapon Systems Officer (was Navigator) in the RAF with a really keen interest in the use of ADS-B in General Aviation. 👍

Thanks Graham. I’ll show you a few Air-to-Air examples in a moment. But we have a network of amateur built and maintained ADS-B receivers in the UK (some are for UK system called Pilot Aware and some for things like Flight Radar 24). The Pilot Aware system has just launched a range analysis tool that shows what range and azimuth from your aircraft that your CAP1391 device (read SkyEcho) was received at (it is important to note that this shows the “up to the maximum range” that you flew from the ground station - so if the receiver is at your airfield and you stay in the circuit, then you may only see 2nm). The period of data can be set, so this is the 30 day data for a SkyEcho in an all-metal PA28 at a relatively busy flying school - sorry the data is in km. So, as these are amateur ground stations using say 7dB antennae, are the Airservices Australia ADS-B and WAM receivers giving you any better than say 20-25km for reliable tracking as shown here? If anyone has a screen shot of the performance of Airservices Australia’s reception range, then I’d be really grateful if they could share it. Moving onto SkyEcho’s receiver performance Air-to-Air, then for a reliable detection and track, I tend to get up to 5nm for PowerFLARM, 20-25nm for a Class 2 Mode S ES transponder in a light aircraft (emitting between 70W to 170W) and up to 120nm for a Class 1 Mode S ES transponder in an airliner (emitting between 250W to 500W). In the above image you can see my aircraft detecting a PowerFLARM (4067E9) at around 5nm and a Vans RV8 (G-RVFT) at around 20nm. This image is the SkyEcho picking up 500W airliners whilst in flight. As you can see, there are some that are 110nm away to the North. I hope that helps with the debate that you have been having on this forum. I would be grateful for your experiences with certified ADS-B systems. We don’t have SDA=1 in our SkyEchos (yet), so knowing what range you are detected by the certified systems of Airservices Australia would be really useful. Further, whilst you won’t generate a TCAS/ACAS RA, you will show up on Boeing and Airbus CDTI (Cockpit Display of Traffic Information) and ATSAW (Air Traffic Situational Awareness) displays. So if any of you have data on the detection of SkyEcho by airliners using CDTI and ATSAW then that would also be great. As I say, we don’t have SDA=1 in the UK yet, so certified ADS-B In doesn’t display us at present (we’re hoping that will change in the New Year). Best, Gaz

Hi, I’m a Pom that has been using SkyEcho in the UK for the past 3 years. Firstly with SkyEcho1 and then with SkyEcho2 later on. In the UK our plan is to use it mainly for Air-to-Air, whereas in Oz I believe the grand plan is to use it for Air-to-Air and Air-to-Ground using Airservices Australia’s WAM and ADS-B set ups. What sort of ranges are you getting picked up at with Airservices Australia? If you have any questions on my experience with SkyEcho, the UK UAT trial and FLARM reception then fire away. Best, Gaz