Primarily for general aviation discussion, but other aviation topics are also welcome.
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By rjc101
#1705144
gaznav wrote:
T67M wrote:
gaznav wrote:
Before you go Lee, then why not offer an option/module for PAW to emit SIL=0 CAP1391 low-power ADS-B Out? That would shut me up on the subject then? :thumright:


Are you going to pay for it, gaznav? About half a million pounds should do the job, maybe a million for SIL=1. (Note, that's a very wet finger in the wind estimate, but from my experience in another regulated industry, it's realistic if not a little on the low side.)


£500,000 to develop an ADS-B Out transmitter to this spec: https://publicapps.caa.co.uk/docs/33/CA ... PR2018.pdf

Why so expensive? The GPS that PAW uses should be fine for SIL=0 so you only need to develop a 20W ADS-B Out module. Are you telling me that SkyEcho 2 took £1,000,000 to develop it’s ADS-B Out transmission capability alone? Crikey, uAvionix will need to sell a lot of units to get that money back!! (NB. I doubt they spent that sort of money).

Sorry, I find those figures hard to believe - I’ve asked my brother in law who runs a company that makes datalink equipment for the emergency services. He didn’t talk about anything like that cost to develop something like this. From what I understand, the Declaration of Capability and Conformance process for CAP1391 devices is relatively cheap and straight forward. So where is the significant cost?


Having been involved too in the emergency services, data links, and safety of life systems, I can say that is nothing compared to anything when you add aviation into the mix. Just the product liability insurance is an eye opener.

Just look at some of the standards mentioned in CAP1391, the GPS receiver side is very easy. There are an number out there you can buy off the shelf, some even designed for aviation use, so we can side step that element.

Code: Select allThe technical requirements set out are based on a number of overarching regulations and specifications that many manufacturers will already be familiar with. These include:

Air Navigation: The Air Navigation Order 2016 and Regulations CAP 393 Fifth edition Amendment 1024, as amended and updated from time to time (Statutory Instrument 2016 No. 765 Civil Aviation The Air Navigation Order 2016 is reproduced in full).

British Civil Airworthiness Requirements (BCAR) Section R – Radio Issue 4 April 1974

Commission Implementing Regulation (EU) No 1207/2011 of 22 November 2011, laying down requirements for the performance and the interoperability of surveillance for the single European sky

EASA Certification Specifications CS-23 Amendment 5 Normal, Utility, Aerobatic and Commuter Aeroplanes27 and CS-27 Amendment 3 Small Rotorcraft

ICAO Annex 10 Volume IV Fifth Edition July 2014: Surveillance Radar and Collision Avoidance Systems

RTCA DO-260B/EUROCAE ED-102A with Corrigendum 1, Minimum Operational Performance Standards for 1090MHz Extended Squitter Automatic Dependant Surveillance – Broadcast (ADS-B) and Traffic Information Services – Broadcast (TIS-B) December 2011/January 2012


Physically building an ADSB transmitter is "reasonably" straightforward if you, and /or your team, are OK with FPGAs, RF systems design, power supply design, PCB design and layout, and mechanical design integration. The standards are explicit as to what is needed.

However getting the certification and testing performed, in certified labs, whose results will be accepted in all the various regulatory areas is horrendously, I will repeat that, horrendously expensive. You need to prove, without absolutely no doubt, that in ALL operational and potential failure modes your ADSB transmitter will not impact any other aircraft systems within range. That isn't just the RF side, but also the way it handles and processes data. Ignore data that cannot be right etc. You are testing the hardware and software/firmware.

Heaven forbid you also want to have it actually certified, for the likes of a TSO. Then before you start you need to be a Design Authority (if you're not already, well, you're in for a treat there). You cannot submit a product for TSO approval unless you are, or can work with a company that is who is happy to share the risk with you. For a price. If they trust you.

Certification labs are book months in advance, as you will almost certainly need to do more than one round of testing. Unless you get EVERYTHING perfect first time around. Then there is PCB fabrication and assembly, which all also forms part of your approval. You can't just start building and testing in your lab/office (see below).

Enclosure design will, probably, need some new injection moulds - depending on what you get done where, no doubt with a minimum order run. This also needs testing, proving it doesn't catch fire or emit fumes etc. if it does (or is involved in a fire).

The phrase "only need to develop a 20W ADS-B Out module" is a very simplistic statement for what could have potentially huge impacts to aviation of you get it wrong.

Even a 20W airborne transmitter will have a huge radius of coverage, say 100nm? Imagine if you, through a small error in the design or software, trigger a TCAS alert on 20 airliners. Or go bonkers and 'jam' and ADSB frequencies with rubbish. Have a few bits of error every x cycles of transmission.

(from above) You can't just build one and test it, you need to test it inside an anechoic chamber, or plugged into an ADSB tester/certification unit, in a shielded environment (get your cheque book out for one of these). You will also, almost certainly, have to perform tests in the air with the approval and by arrangement with your local authority, the CAA and NATS here I suppose. To ensure that what is transmitted will work with the systems in the ground, and that you don't cause trouble in the air, so they can help sort the mess out if you do.

You could burn through quite a stack of cash and time to "only .... develop a 20W ADS-B Out module". If you could do it for under £0.75m and a couple of years then get together with few people and get your soldering irons out, you could make a killing selling OEM ADSB-Out modules. You will need a chunk of venture capital, as you won't get any return on investment until it's ready to go, boxes ticked, and paperwork all in order. *

Dropping back to the emergency services for a moment. The new Emergency Services Network (ESN) to replace AirWave, is built using 4G mobile technology. So it should be simple to "just create a communications network, on top of a communication network", shouldn't it? It's years late, and way, way, over budget (£100's of millions over). It's all "standard stuff" but it's more critical than you being able to phone the AA if a wheel comes off. So it takes time, and money, lots of money, to get that right.

* you may have noticed that despite ADSB having been around for quite some time, no one has done this yet. I wonder why?
Last edited by rjc101 on Tue Jul 09, 2019 11:08 pm, edited 2 times in total.
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By Smaragd
#1705148
I'm lost.
gaznav wrote:
Why so expensive? The GPS that PAW uses should be fine for SIL=0 so you only need to develop a 20W ADS-B Out module. Are you telling me that SkyEcho 2 took £1,000,000 to develop it’s ADS-B Out transmission capability alone? Crikey, uAvionix will need to sell a lot of units to get that money back!! (NB. I doubt they spent that sort of money).

Sorry, I find those figures hard to believe - I’ve asked my brother in law who runs a company that makes datalink equipment for the emergency services. He didn’t talk about anything like that cost to develop something like this. From what I understand, the Declaration of Capability and Conformance process for CAP1391 devices is relatively cheap and straight forward. So where is the significant cost?


And then Tim says:
Tim Dawson wrote:It is not reasonable or fair to suggest that PilotAware could have ADSB out added to it cheaply. It would be very expensive for the people that built it to add that sort of capability.


And Gaznav gives Tim's message a Like. :roll: No wonder Lee want to dip out of this thread.

I'm just glad of the increasing capability that PAW brings me, now. Well done, team!
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By gaznav
#1705161
Smaragd wrote:I'm lost.

And then Tim says:
Tim Dawson wrote:It is not reasonable or fair to suggest that PilotAware could have ADSB out added to it cheaply. It would be very expensive for the people that built it to add that sort of capability.


And Gaznav gives Tim's message a Like. :roll: No wonder Lee want to dip out of this thread.

I'm just glad of the increasing capability that PAW brings me, now. Well done, team!


I ‘liked’ Tim’s post as it kind of answers my question - but then I have asked some more?
User avatar
By T67M
#1705162
gaznav wrote:Thanks Tim, that’s a useful statement, is there any reason why it would be so expensive to have a signal output on 1090 MHz rather than 869.5 MHz. I know the waveforms, frequencies and power outputs are different, but I always thought it was the ‘PAW Bridge’ that does the P3i transmission - so wouldn’t it just need a different ‘Bridge’ and a Raspberry Pi reprogram? Seeing as the later PAW Rosetta ‘Bridges’ sold for (I think?) £80-odd plus VAT, I am sure there are people out there that would pay double that if it meant they could output CAP1391 low-power ADS-B without junking the rest of their electronics? Or is that the supporting hardware could not handle that sort of power output rising from 0.5W for P3i to 20W for ADS-B?

Sorry for the 1,000 questions, but I am just keen to understand what would make it so expensive.


The PilotAware "Bridge" uses a commercially available OEM (Original Equipment Manufacturer) module designed to be built into millions of cheap electronic devices (think garage door openers). Whilst an OEM module comes "approved" for use and compliant with the regulations, significant further testing is required before that OEM module can be sold as part of a finished product. Whilst I wasn't involved in that testing - I'm not part of the PAw team, just one of the very early adopters - I do recall that the PAw team spend a long time and (I'm guessing again) a lot of money going through the formal certification programme required to embed the OEM module into a finished piece of equipment. I don't know how much it cost them, but in my day job I'd expect it to be a six figure sum. And that's just to embed an already designed, tested and approved OEM module into a piece of equipment.

There are no OEM modules for ADS-B (unless uAvionix want to sell one! :wink: )

Without an OEM module, in order to emit ADS-B you would have to do a ground-up design and complete the full certification process to DO-260B (as required by CAP1391 section 6.5). That's not going to be cheap, and it certainly isn't "just" moving PAw from 869.5MHz to 1090MHz and changing a few bits in the software.

Don't get me wrong, uAvionix have done a remarkable job to secure funding to develop a miniature, low power ADS-B module - whether it's on 978MHz or 1090MHz actually makes relatively little difference, and if I was designing it I would design a dual-band module from day one simply to reduce the testing costs. But it's not a cheap or quick process. I'd forgotten that uAvionix's original market was drones (apologies) but I stand by my earlier statement that the only way they can hope to recoup the cost is to sell the same intellectual property and the same module into many different market sectors, and even with the ADS-B mandate, I suspect that the recent DJI announcement is music to the ears of the investors who are probably just starting to think they might get their money back.

It is worth remembering that even in the field of proper transponders, there are actually only two core modules available for GA aircraft, with almost all GA transponders actually being the Trig module in a different box. Even Bendix King didn't develop their own - it's just too expensive. OK, the higher power of a transponder compared to a CAP1391 device will increase the cost very slightly, but in fact most of the cost is in the design and certification to DO-260B.
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By T67M
#1705165
gaznav wrote:
Smaragd wrote:I'm lost.

And then Tim says:
Tim Dawson wrote:It is not reasonable or fair to suggest that PilotAware could have ADSB out added to it cheaply. It would be very expensive for the people that built it to add that sort of capability.


And Gaznav gives Tim's message a Like. :roll: No wonder Lee want to dip out of this thread.

I'm just glad of the increasing capability that PAW brings me, now. Well done, team!


I ‘liked’ Tim’s post as it kind of answers my question - but then I have asked some more?


Tim's "answer" doesn't say anything that hasn't been said to you several times before over the last 18 months.
User avatar
By gaznav
#1705168
rjc101 wrote:
gaznav wrote:
T67M wrote:
Are you going to pay for it, gaznav? About half a million pounds should do the job, maybe a million for SIL=1. (Note, that's a very wet finger in the wind estimate, but from my experience in another regulated industry, it's realistic if not a little on the low side.)


£500,000 to develop an ADS-B Out transmitter to this spec: https://publicapps.caa.co.uk/docs/33/CA ... PR2018.pdf

Why so expensive? The GPS that PAW uses should be fine for SIL=0 so you only need to develop a 20W ADS-B Out module. Are you telling me that SkyEcho 2 took £1,000,000 to develop it’s ADS-B Out transmission capability alone? Crikey, uAvionix will need to sell a lot of units to get that money back!! (NB. I doubt they spent that sort of money).

Sorry, I find those figures hard to believe - I’ve asked my brother in law who runs a company that makes datalink equipment for the emergency services. He didn’t talk about anything like that cost to develop something like this. From what I understand, the Declaration of Capability and Conformance process for CAP1391 devices is relatively cheap and straight forward. So where is the significant cost?


Having been involved too in the emergency services, data links, and safety of life systems, I can say that is nothing compared to anything when you add aviation into the mix. Just the product liability insurance is an eye opener.

Just look at some of the standards mentioned in CAP1391, the GPS receiver side is very easy. There are an number out there you can buy off the shelf, some even designed for aviation use, so we can side step that element.

Code: Select allThe technical requirements set out are based on a number of overarching regulations and specifications that many manufacturers will already be familiar with. These include:

Air Navigation: The Air Navigation Order 2016 and Regulations CAP 393 Fifth edition Amendment 1024, as amended and updated from time to time (Statutory Instrument 2016 No. 765 Civil Aviation The Air Navigation Order 2016 is reproduced in full).

British Civil Airworthiness Requirements (BCAR) Section R – Radio Issue 4 April 1974

Commission Implementing Regulation (EU) No 1207/2011 of 22 November 2011, laying down requirements for the performance and the interoperability of surveillance for the single European sky

EASA Certification Specifications CS-23 Amendment 5 Normal, Utility, Aerobatic and Commuter Aeroplanes27 and CS-27 Amendment 3 Small Rotorcraft

ICAO Annex 10 Volume IV Fifth Edition July 2014: Surveillance Radar and Collision Avoidance Systems

RTCA DO-260B/EUROCAE ED-102A with Corrigendum 1, Minimum Operational Performance Standards for 1090MHz Extended Squitter Automatic Dependant Surveillance – Broadcast (ADS-B) and Traffic Information Services – Broadcast (TIS-B) December 2011/January 2012


Physically building an ADSB transmitter is "reasonably" straightforward if you, and /or your team, are OK with FPGAs, RF systems design, power supply design, PCB design and layout, and mechanical design integration. The standards are explicit as to what is needed.

However getting the certification and testing performed, in certified labs, whose results will be accepted in all the various regulatory areas is horrendously, I will repeat that, horrendously expensive. You need to prove, without absolutely no doubt, that in ALL operational and potential failure modes your ADSB transmitter will not impact any other aircraft systems within range. That isn't just the RF side, but also the way it handles and processes data. Ignore data that cannot be right etc. You are testing the hardware and software/firmware.

Heaven forbid you also want to have it actually certified, for the likes of a TSO. Then before you start you need to be a Design Authority (if you're not already, well, you're in for a treat there). You cannot submit a product for TSO approval unless you are, or can work with a company that is who is happy to share the risk with you. For a price. If they trust you.

Certification labs are book months in advance, as you will almost certainly need to do more than one round of testing. Unless you get EVERYTHING perfect first time around. Then there is PCB fabrication and assembly, which all also forms part of your approval. You can't just start building and testing in your lab/office (see below).

Enclosure design will, probably, need some new injection moulds - depending on what you get done where, no doubt with a minimum order run. This also needs testing, proving it doesn't catch fire or emit fumes etc. if it does (or is involved in a fire).

The phrase "only need to develop a 20W ADS-B Out module" is a very simplistic statement for what could have potentially huge impacts to aviation of you get it wrong.

Even a 20W airborne transmitter will have a huge radius of coverage, say 100nm? Imagine if you, through a small error in the design or software, trigger a TCAS alert on 20 airliners. Or go bonkers and 'jam' and ADSB frequencies with rubbish. Have a few bits of error every x cycles of transmission.

(from above) You can't just build one and test it, you need to test it inside an anechoic chamber, or plugged into an ADSB tester/certification unit, in a shielded environment (get your cheque book out for one of these). You will also, almost certainly, have to perform tests in the air with the approval and by arrangement with your local authority, the CAA and NATS here I suppose. To ensure that what is transmitted will work with the systems in the ground, and that you don't cause trouble in the air, so they can help sort the mess out if you do.

You could burn through quite a stack of cash and time to "only .... develop a 20W ADS-B Out module". If you could do it for under £0.75m and a couple of years then get together with few people and get your soldering irons out, you could make a killing selling OEM ADSB-Out modules. You will need a chunk of venture capital, as you won't get any return on investment until it's ready to go, boxes ticked, and paperwork all in order. *

Dropping back to the emergency services for a moment. The new Emergency Services Network (ESN) to replace AirWave, is built using 4G mobile technology. So it should be simple to "just create a communications network, on top of a communication network", shouldn't it? It's years late, and way, way, over budget (£100's of millions over). It's all "standard stuff" but it's more critical than you being able to phone the AA if a wheel comes off. So it takes time, and money, lots of money, to get that right.

* you may have noticed that despite ADSB having been around for quite some time, no one has done this yet. I wonder why?


Thanks for that, useful stuff. Why would you not run your 1090 MHz output into a dummy load so that it doesn’t radiate on frequency? If you are really that worried then build a Faraday Cage to test it within to contain any last stray wigglies? It is only 20W, and at 1GHz too, so penetration of building walls, etc... will be poor and you needn’t test initially at max power output anyway?

As for the other processes, I thought the whole idea of CAP1391 was to make the process easier. It is nothing like a TSO process, and was designed to encourage the rapid capability development without all of the extra ‘nause’ that you describe. This simpler process is described in CAP1391 around page 28 onwards - https://publicapps.caa.co.uk/docs/33/CA ... PR2018.pdf

The paperwork required is SRG1757 which is here: http://publicapps.caa.co.uk/docs/33/SRG ... nabled.pdf

So whilst I accept building a certified product for fitment inside a certified aircraft - this simplified procedure in CAP1391 allows manufacturers the leeway to produce a portable carry-on low-power transceiver through a far simpler process than before.

Yes, last year’s re-think of the emergency services contract provision for another 3 years was a bit of a shocker!
User avatar
By gaznav
#1705170
T67M wrote:
gaznav wrote:Thanks Tim, that’s a useful statement, is there any reason why it would be so expensive to have a signal output on 1090 MHz rather than 869.5 MHz. I know the waveforms, frequencies and power outputs are different, but I always thought it was the ‘PAW Bridge’ that does the P3i transmission - so wouldn’t it just need a different ‘Bridge’ and a Raspberry Pi reprogram? Seeing as the later PAW Rosetta ‘Bridges’ sold for (I think?) £80-odd plus VAT, I am sure there are people out there that would pay double that if it meant they could output CAP1391 low-power ADS-B without junking the rest of their electronics? Or is that the supporting hardware could not handle that sort of power output rising from 0.5W for P3i to 20W for ADS-B?

Sorry for the 1,000 questions, but I am just keen to understand what would make it so expensive.


The PilotAware "Bridge" uses a commercially available OEM (Original Equipment Manufacturer) module designed to be built into millions of cheap electronic devices (think garage door openers). Whilst an OEM module comes "approved" for use and compliant with the regulations, significant further testing is required before that OEM module can be sold as part of a finished product. Whilst I wasn't involved in that testing - I'm not part of the PAw team, just one of the very early adopters - I do recall that the PAw team spend a long time and (I'm guessing again) a lot of money going through the formal certification programme required to embed the OEM module into a finished piece of equipment. I don't know how much it cost them, but in my day job I'd expect it to be a six figure sum. And that's just to embed an already designed, tested and approved OEM module into a piece of equipment.

There are no OEM modules for ADS-B (unless uAvionix want to sell one! :wink: )

Without an OEM module, in order to emit ADS-B you would have to do a ground-up design and complete the full certification process to DO-260B (as required by CAP1391 section 6.5). That's not going to be cheap, and it certainly isn't "just" moving PAw from 869.5MHz to 1090MHz and changing a few bits in the software.

Don't get me wrong, uAvionix have done a remarkable job to secure funding to develop a miniature, low power ADS-B module - whether it's on 978MHz or 1090MHz actually makes relatively little difference, and if I was designing it I would design a dual-band module from day one simply to reduce the testing costs. But it's not a cheap or quick process. I'd forgotten that uAvionix's original market was drones (apologies) but I stand by my earlier statement that the only way they can hope to recoup the cost is to sell the same intellectual property and the same module into many different market sectors, and even with the ADS-B mandate, I suspect that the recent DJI announcement is music to the ears of the investors who are probably just starting to think they might get their money back.

It is worth remembering that even in the field of proper transponders, there are actually only two core modules available for GA aircraft, with almost all GA transponders actually being the Trig module in a different box. Even Bendix King didn't develop their own - it's just too expensive. OK, the higher power of a transponder compared to a CAP1391 device will increase the cost very slightly, but in fact most of the cost is in the design and certification to DO-260B.


Thank you very much - I think I now understand. :thumleft:

I also now understand @Tim Dawson’s post. Thank you, Tim.

So in summary, the opportunity for PAW to operate an ADS-B Out transmit function has long since passed (which is a real shame) and it will only ever transmit P3i. So unless other manufacturers develop a P3i receive-only capability, then other devices will never detect a PAW user. So I guess time will tell whether uAvionix or FLARM will embody that receive capability into their devices in the future - but they will have to decide whether ‘the juice is worth the squeeze’ with relatively small number of PAW users compared to that of ADS-B/FLARM (globally and in the UK).

That’s a real shame...
By rjc101
#1705172
Why would you not run your 1090 MHz output into a dummy load so that it doesn’t radiate on frequency?


Because you need to be able to measure the signals coming out, both for frequency, power, and modulation.

If you are really that worried then build a Faraday Cage to test it within to contain any last stray wigglies? It is only 20W, and at 1GHz too, so penetration of building walls, etc... will be poor and you needn’t test initially at max power output anyway?


Good luck with that, you need a proper chamber. Anything that leaks out could be a problem. Are you willing to take the risk? You must test a full working power, little point otherwise. Remember you also need to keep all those real high power ADSB signals out, as they will impact your testing too. Such chambers are expensive to build.

As for the other processes, I thought the whole idea of CAP1391 was to make the process easier. It is nothing like a TSO process, and was designed to encourage the rapid capability development without all of the extra ‘nause’ that you describe.

So whilst I accept building a certified product for fitment inside a certified aircraft - this simplified procedure in CAP1391 allows manufacturers the leeway to produce a portable carry-on low-power transceiver through a far simpler process than before.


I stand by my post, I wasn’t even thinking about going TSO. Do you think any regulatory authority would let you switch an ADSB transmitter on, in the air, without going through even basic conformance testing? You’d never get product liability insurance either.

ADSB is a complex, time critical, protocol down at the transmission level.

Having been through testing for various products, not even designed to radiate RF, it’s expensive and slow. Add in you are testing an intentional radiator too that must also be shown to transmit the right stuff. Basic EMC lab testing will show you radiate at the right frequency and power. You then also need to prove that *what* you transmit is within the specs. Again needs a proper environment and gear to do that, safely.

Throw in too I suspect you need to show it doesn’t go bonkers when radiated itself (immunity testing) and the fun just gets going.

Before making any further rash comments that “it’s only just...”, take it from people who have the scars. It isn’t and never is just.,.
Last edited by rjc101 on Wed Jul 10, 2019 7:48 am, edited 1 time in total.
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By T67M
#1705173
gaznav wrote:
T67M wrote:[snip]

Thank you very much - I think I now understand. :thumleft:

Excellent - glad to have helped.
gaznav wrote:So in summary, the opportunity for PAW to operate an ADS-B Out transmit function has long since passed (which is a real shame) and it will only ever transmit P3i. So unless other manufacturers develop a P3i receive-only capability, then other devices will never detect a PAW user. So I guess time will tell whether uAvionix or FLARM will embody that receive capability into their devices in the future - but they will have to decide whether ‘the juice is worth the squeeze’ with relatively small number of PAW users compared to that of ADS-B/FLARM (globally and in the UK).

That’s a real shame...


Not quite. As has been said here many, many times, the PilotAware team never had the resources to produce an ADS-B out function. It's not that they "missed" the chance, or that they "chose" not to do it out of sheer bloody-mindedness. They are a small group of maybe four people who are putting a lot of their own time and money into trying to build a useful tool for GA pilots, and continue to do so despite the best efforts of people here telling them that they've got it wrong. Thank you, @leemoore1966.
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By johnm
#1705191
There is no ideal answer from where we are. because there's no consistent equipment fit. So if one has certified ADS-B out then PAW looks like the best overall compromise. If it did FLARM direct it would be darn near perfect as a receiver.
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By Tim Dawson
#1705193
It might be worth asking them if they’d consider receiving flarm direct, with the same mechanism that uavionix use. If my understanding is correct, it isn’t difficult but just requires another radio module.
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By Flyin'Dutch'
#1705196
Tim Dawson wrote:It might be worth asking them if they’d consider receiving flarm direct, with the same mechanism that uavionix use. If my understanding is correct, it isn’t difficult but just requires another radio module.


The additional cost for that could be recouped by omitting the Pi transmitter and the resulting product could be sold as an EC receiver.
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By Balliol
#1705202
There’s a lot of tech stuff above that went over my head, but am I right in thinking then that the motivation / benefit of the P3i transmission route is that the electronics to do it can avoid having to go through the detailed certification and testing that ADSB electronics would have to?
By rjc101
#1705207
Balliol wrote:There’s a lot of tech stuff above that went over my head, but am I right in thinking then that the motivation / benefit of the P3i transmission route is that the electronics to do it can avoid having to go through the detailed certification and testing that ADSB electronics would have to?


I think the original idea was to have something like FLARM but with a longer range and without the encryption. You have to update FLARM every year as they change the encryption keys. FLARM is, from memory 50mW TX power and PAW is 500mW.

When FLARM made the Power FLARM for GA aircraft you will note they didn’t include an ADSB out module either.

Testing is still required for the likes of PAW, you have to be sure it doesn’t interfere with other equipment or be impacted by emissions from other things. That would have taken several days at an EMC testing facility. Even this basic testing is going to be many £1000’s per cycle.

Ironically if you make a product for aviation you can sidestep the normal regulatory testing for then likes of a CE mark. But the testing with be orders of magnitude more expensive, not many sites are certified to handle avionics stuff.
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By stevelup
#1705208
gaznav wrote:Are you telling me that SkyEcho 2 took £1,000,000 to develop it’s ADS-B Out transmission capability alone? Crikey, uAvionix will need to sell a lot of units to get that money back!! (NB. I doubt they spent that sort of money)


uAvionix almost certainly have spent a 7 figure $$$ in R&D developing their whole suite of products. I really don't find that difficult to believe at all.

They already sell a fully self-contained 20W 1090MHz ADS-B transponder. It weighs 20g and measures just 50x25x17mm.

https://uavionix.com/products/ping20si/

It would be trivial to integrate this into PAW were it not for the fact that it is staggeringly expensive.
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