Messages

31

Technical Support / Re: Incorrect GPS position sent to Trig TT22

« on: September 16, 2022, 06:07:19 pm »

The NMEA sentences have a checksum, so I can't see it being data corruption.  I suspect if you go for a flight the trig display will be correct, even if you don't enable the output.

32

Technical Support / Re: Incorrect GPS position sent to Trig TT22

« on: September 16, 2022, 01:45:09 pm »

What does a flight tracking website say is your position compared to a SkyDemon track? I.e. is it actually wrong or is this just a display issue?

33

Technical Support / Re: iGrid connection to hotspot flakey - Solution is to open on hotspot page

« on: August 20, 2022, 05:28:10 pm »

Re the cellular coverage issue - we are finding that, perhaps counter-intuitively, cellular coverage can in fact be WORSE when you can see MORE telecom masts, though testing to determine the optimal installation is currently ongoing. Watch this space!

The handset will be hitting multiple masts, so probably flip-flopping between base stations.  I vaguely remember reading a paper on the new ESN and how aircraft would be integrated.  I think it required 100's more new and modified EE base stations handling aircraft at 500 - 10,000 ft, but it would need new specifically designed hardware for the airframes too.  In theory, EE would be the better bet for in-air use, but I suspect access to these masts may well be restricted to ESN users.

The ESN was due to go live in 2019, it's looking more like 2026 now.  Only 7 years late, pretty good going.  The catchphrase when installing Airwave was "yesterdays technology, tomorrow", I wonder what the ESN one is now...

34

Technical Support / Re: What should I see/hear tuned to 869.525Mhz with a Software Defined Radio?

« on: August 14, 2022, 12:30:37 pm »

Ideally, the whole thing, unless Lee can sort me out a temp licence for a spare Pi to install PAW onto? 
I borrowed the Pi from my previous test bench to fix something else that had an "accident" during some development work...

Drop me a PM here or send me a mail to the address on the Charge4 website and I'll give you the address, or take it from the invoice from your charger purchase.  Return shipping would be £12 + VAT.

Lee, I have a spare Pi 3 Model B v1.2 is that suitable? Would I just need to send you the MAC address from the PAW status page on it?  The Host ID of my spare Pi is B827EB23B6C6 

35

Technical Support / Re: What should I see/hear tuned to 869.525Mhz with a Software Defined Radio?

« on: August 11, 2022, 08:37:07 pm »

Excellent in the charger!
Your welcome to post it, the only “fee” is the return shipping. Take so very little time to actually test it.

36

Technical Support / Re: What should I see/hear tuned to 869.525Mhz with a Software Defined Radio?

« on: August 11, 2022, 07:00:13 pm »

The transmissions are a few milliseconds every second or so.  An SDR probably can pick them up, if you have a waterfall plot you may be able to see it pulsing.  It won't transmit if it doesn't have a GPS fix, though.  It won't give you an accurate power output, but it should at least show some activity.

I test PAW Bridge RF output with a real-time spectrum analyser.  The only way to be able to determine the effective transmitted power coming out of the SMA connector on the bridge.  This also verifies the frequency is correct too.  I do this on any PAW bridge I fix the SMA connector on to verify the repair.  Only takes a few mins to run the tests, if you're near Cambridge happy to test it.

37

Technical Support / Re: Loading PAW onto a Raspberry Pi 4

« on: July 20, 2022, 04:07:01 pm »

Replacing the power USB socket on a Pi is a simple thing (if you have the right gear), and I have spare sockets on the shelf.

After a rummage I do also have a single spare Raspberry Pi 3 B, I had two but best not go into why I'm down to the one.

38

Technical Support / Re: Loading PAW onto a Raspberry Pi 4

« on: July 19, 2022, 10:09:19 pm »

If it's SD card connector, may be able to reflow that.  Not sure if I have and space connectors handy though, got plenty of Pi power connectors.

39

Technical Support / Re: Loading PAW onto a Raspberry Pi 4

« on: July 19, 2022, 10:04:00 pm »

Only next year, pfffft. I went to order some parts, 117 week lead time.  Have multiple back orders in all over the place for parts.

I might have a spare Raspberry Pi 3 of some variety knocking around though, need to check.  Do you need a 3 B+ ?

40

Technical Support / Re: iGrid connection to hotspot flakey as hell. - An Update

« on: July 13, 2022, 07:01:01 am »

You have 12 channels to choose from.

Actually you don’t. For 2.4GHz based WiFi only channels 1, 6, and 11 don’t overlap with other channels.  With 5GHz, unless you up the bandwidth by bonding, none of the channels overlap.

41

Technical Support / Re: Aircrew Instrument Firmware Update

« on: July 10, 2022, 02:09:57 pm »

SDR’s get hot, they are rated to 85degC, we gave pushed them and the PI (by increasing ambient temperature and workload) to over 100 degC without issue
Jeremy, are you running the SDR under workload, or just plugged int USB ?
Just plugging in will not necessarily generate heat
Thx
Lee

Oh, it’s working hard…  as the Pi 4 it’s connected too.

42

Technical Support / Re: Aircrew Instrument Firmware Update

« on: July 10, 2022, 11:36:33 am »

How do you tell if something has gone a bit iffy, normally they quickly get very hot after power on.

That is the bit that worries me. It does get hot quickly but I'm told that the SDR card does generate a lot of heat.

I have an SDR on the bench here, been running flat out for a week.  Checking it with a FLIR camera, it's holding at 40℃, I can hold it OK - it's warm, but not uncomfortable.  When things are too hot to touch, then I'd say there is a problem.

SDR's are very inefficient, hence they generate a lot of heat.  A WiFi dongle or GPS in comparison should not really get warm at all.  A USB to serial adapter should never be above ambient.

43

Technical Support / Re: IGrid WiFi

« on: July 10, 2022, 11:19:20 am »

All of these features are addictive, and not mutually exclusive
We have found that using data from multiple sources ensures maximum system redundancy
So adding iGRID, loses nothing
Thx
Lee

Or additive?

44

Technical Support / Re: Aircrew Instrument Firmware Update

« on: July 10, 2022, 10:54:24 am »

OK, so the total available to all 4 USB ports combined is physically limited to 1200ma - or there will be issues.

Is it possible to work out the total draw when all 4 USB ports are in use? In my case:

1. GPS Mouse
2. WiFi Dongle
3. USB to RS232 Serial Adapter - GPS to Trig for ADSB out
4. SDR

GPS probably 50ma max
WiFi maybe 200ma max
USB-RS232 I'd be surprised if more than 20ma, but call it 50ma max.
SDR is the biggest, could be up to 300ma depending on model, so lets say 400ma max

So this gives, 700ma max from the USB ports.  But if any of these goes a bit iffy, then all will suffer as a result.

How do you tell if something has gone a bit iffy, normally they quickly get very hot after power on.

I haven't measured a Rosetta boot and running power, but the older classic was running at a peak of ~1300ma.  The consumption of a PAW system isn't steady state by any means, it's very bursty and totally different to charging a battery.  I can't find the dataset just a low quality screen grab of around a couple of seconds of current consumption from back in the dark ages (2016).  The PAW does more work than it did back then, maybe I need to dig out my Classic or build a Rosetta and take some up to data measurements....

45

Technical Support / Re: Aircrew Instrument Firmware Update

« on: July 10, 2022, 09:45:33 am »

Hi All,

Thanks Jeremy. Pi of choice is Model 2B for the Classic and Model 3B for Rosetta.

Best Regards
Peter

OK, so the total available to all 4 USB ports combined is physically limited to 1200ma - or there will be issues.