Messages

3166

General Discussion / Re: FLY IN AT FENLAND SATURDAY 19th SEPT - PILOTAWARE HOTSPOT FOR THE DAY?

« on: September 17, 2015, 08:38:34 pm »

All

We have tested (on the ground) all 7 of our PilotAwares so far built.  We have to add the barometric sensor next week.  But will take them all to Fenland on Saturday. Some will be flying!

Dave T

Hi Dave,

I presume by tested, they could all see each other ?
Did you have all booted and running at the same time, or were you testing in pairs, what was the
test scenario

thx
Lee

3167

General Discussion / Re: Testing ARF with a TV tuner

« on: September 17, 2015, 05:43:52 pm »

I recall somebody was using and SDR_RTL to decode the PilotAware traffic, I will see if I can find the email thread

3168

General Discussion / Re: FLY IN AT FENLAND SATURDAY 19th SEPT - PILOTAWARE HOTSPOT FOR THE DAY?

« on: September 17, 2015, 05:42:06 pm »

just out of interest, when showing PilotAware at the LAA rally I wanted an Antenna I could place outside of the marquee
I purchased one of these

http://www.ebay.co.uk/itm/868MHZ-915MHZ-GSM-3G-Small-99-UK-Omnidirectional-High-gain-Antenna-7DBI-/171802354402?hash=item280037e2e2

Just wondering if this would be useful for your control tower

3169

General Discussion / Re: Help for PilotAware Virgin

« on: September 17, 2015, 05:38:53 pm »

Having got the unit completed I needed to test it, so this afternoon sat under the take-off flight path of Leeds Bradford.

Total disappointment. No other little yellow plane silhouettes on the iPad ( running Sky Demon with Garmin Glo)

No problems with Wi Fi or Flamm connection etc
In the blue line at the top pf the screen it said it was using the services, or words to that effect
I am not using either of the new Upgrade, just the original version
The power was via the car's 12volt outlet / USB fitting. Could see lights on in the R-Pi Case
I wonder about the ADS-B Dongle as I have seen the bragging rites on the blog about some Dongles!
I bought mine from Ali Express, described as : Mini USB-T USB 3.0 SDR & DVB-T receiver RTL2823U +R802 Tuner Black


What do you think needs checking and in what order of likely cause??
Please

Sorry to hear this.
Couple of things to confirm

1. are all of the traffic filters disabled, ie able to view traffic +/- 40000ft ?
2. have you booted with a monitor attached to PilotAware, I would be interested on any messages produced

Thx
Lee

3170

General Discussion / Re: Testing ARF with a TV tuner

« on: September 17, 2015, 02:15:32 pm »

easy to rig up the following

http://www.ebay.co.uk/itm/FT232-Brush-USB-To-TTL-Serial-Cable-Line-Electric-Adapter-FTDI-Chipset-Computer-/281739777265?hash=item4198ffd4f1

https://www.wirelessthings.net/erf-0-1-pin-spaced-radio-module

voila, a simple test rig, just setup the parameters on the ERF and it will receive the ARF data

3171

General Discussion / Re: Altitude Accuracy

« on: September 17, 2015, 12:00:24 pm »

Been thinking about the connections for the MPL3115A2 with the Slice of POD.
I think this would be correct (?) ...

This is the version I used
https://www.sparkfun.com/products/11084

Your version looks slightly different, do you have a datasheet ?
It looks like it also has a 3.3v Regulator on board, and the 3.3v is labeled 3vo - is this an output ?
If so I would say it probably requires 5v input rather than 3.3v input - difficult to say without a
datasheet
Thx
Lee

(UPDATE)
Found the Adafruit description

Using the sensor is easy. For example, if you're using an Arduino, simply connect the VDD pin to the 5V voltage pin, GND to ground, SCL to I2C Clock (Analog 5 on an UNO) and SDA to I2C Data....

So this already has a regulator built in - I wonder what it can supply on its 3.3v output ?

3172

General Discussion / Re: Fail on boot up

« on: September 17, 2015, 09:59:24 am »

I have a 2.5 amp power supply on the Pi, but a 2m cable - have changed for a 1m long cable and appears better.  I haven't therefore taken the ARF out.  I will have to look at the aircraft power installation - I have a 5 amp power supply with 4 usb sockets to power pilotaware, iPad and Dual 150 GPS.  Maybe I will make up my own power cable for the pilotaware.
testing continues

I will look at your power supplies from amazon
dave

I would say 2m is way too long. If you need a long power lead, I think you need to rig up a bespoke solution.
I have been using 50cm/20AWG leads which have very low voltage drop.

I went for these 0.5M versions, cannot comment on longer cables
http://www.ebay.co.uk/itm/Heavy-Duty-4mm-OD-20AWG-Pure-Copper-USB-A-to-Micro-B-Fast-Charger-Cable-Lead-/271929181905

3173

General Discussion / Re: Altitude Accuracy

« on: September 17, 2015, 09:56:20 am »

Great Post,
I had no idea some Pressure Sensors were so inaccurate.
The Sensor I have been using seems very good, it claims 30cm of accuracy, which is way above what is required.

My understanding was that Mode S transponders had altitude reporting in steps of 25ft, I cannot find any
information regarding calibration inaccuracy.

Bear in mind that PilotAware is only using information from Mode S using ADS-B or other PilotAware units, so I
was under the assumption that the Mode S figures would be reasonably accurate.

There are situations where Aircraft fitted with both ADS-B and PilotAware would be transmitting 2 Altitude figures
1. The ADS-B Pressure Altitude
2. the P3I GNSS Altitude

At the receiving end, I use ADS-B in preference to PilotAware, in other words I receive 2 records of information with the
same ICAO code, lets say 0x40abcd
0x40abcd (ADSB) Pressure Altitude
0x40abcd (P3I) GNSS Altitude

If I wanted I could change the Altitude transmitted by P3I to be the Pressure Altitude, or even send GNSS & Pressure
altitude on alternating packets with an indicator to identify what is being reported.

I need to think on this a little further to decide which is the best piece of information to use

3174

General Discussion / Re: How do I activate the FLARM function in Simulate mode

« on: September 16, 2015, 10:01:03 pm »

Run in simulate mode
Click in free space and select spawn aircraft
Control directions by dragging with your finger

3175

General Discussion / Digole 3.3v Regulators - anyone who needs them

« on: September 16, 2015, 08:07:12 pm »

Hi All,

I have an (over) supply of 3.3v Digole.com regulators, if anybody needs them, drop
me a PM/Email £4 incl P&P invoiced through PayPal.

thx
Lee

3176

General Discussion / Re: Can any more details shown about other aircraft

« on: September 16, 2015, 06:32:15 pm »

OK, my 2 cents,
I think the type should have a different icon on the display, rather than annotated text
the Reg/ICAO could be annotated text, but need to be careful this does not start to clutter the display,
In fact I would say, if the Reg is present annotate that, else annotate the ICAO

P3I can send the Reg, ADS-B does not have this field available

3177

General Discussion / Re: Altitude Accuracy

« on: September 16, 2015, 06:28:56 pm »

Have ordered two to add to my built boxes - this will fit quite happily to the Slice of Pod board. Again, happy to test the software when I get these installed (5 min jobbie )
The module says its temperature compensated - is there an issue with this getting baked on the instrument panel coaming?
Mark.

I did some hand calculations, and I was not too concerned about the total impact it would have on the altitude figure.
What we are trying to do here is make the figures more accurate, they are never going to be within 30cm which is the
claim on the datasheet.

Unless you know something I don't ?

3178

General Discussion / Re: Altitude Accuracy

« on: September 16, 2015, 06:19:48 pm »

Hi Dave,

Does this mean that if you have an ADSB equipped transponder already fed by an Altitude Encoder the barometric pressure sensor isn't needed - because it is only used if feeding data from pilotaware into a mode s transponder, or is the situation as below

In order for altitudes shown on Skydemon to be comparable with a received ADSB signal the pilotaware will require a barometric sensor (or the QNH updated manually in the web page)?

Complicated, isn't it 

This is nothing to do with the Altitude you are transmitting through your transponder, it is about comparing
relative heights between yourself and surrounding traffic.

ADS-B contains the Pressure Altitude, so altitude based upon an altimiter setting of 1013.25mb.
In order to correctly compare to ADS-B altitude against our own altitude, we need to either
1. Adjust the GNSS altitude using the given QNH
2. Use our own Pressure Altitude

The heights of traffic passed to SD, RunwayHD etc are relative +/- heights to our own position, not absolute heights.
So in order to calculate those relative height differences, in the case of ADS-B, we compare to our Pressure Altitude
in the case of PilotAware we use our GNSS Altitude.
The Navtool simply receives a message indicating the relative traffic height.

I hope that is clear

Thx
Lee

3179

General Discussion / Re: Altitude Accuracy

« on: September 16, 2015, 06:05:30 pm »

Lee
Spoken with the boss (John Parker) - we are going to add the barometric sensor into all our boxes - when you are able to give us the pin outs etc.  We have ordered the magic bit (x10)!!!!!!!
Dave t

Hi Dave,

Its pretty simple actually, it uses the i2c interface, so only 4 wires to connect from the sensor,

GND
    GPIO pin 6, 9, 14, 20, 25 - take your pick !

3.3v
    I have used the 3.3v from the GPIO header pin 1 (for expediency), this is only rated at 50mA, so
    I would recommend using the 3.3v from the regulator if you are able.

SCL
    GPIO pin 5

SDA
    GPIO pin 3

I1
    unconnected

I2
    unconnected

Let me know if that is clear. I will update the build guide at some point.

Thx
Lee

3180

General Discussion / Re: Altitude Accuracy

« on: September 16, 2015, 05:42:08 pm »

Hi Lee

I am presuming there is no room in the existing box to fit the additional barometric pressure sensor - that is the curvy side one pictured.  I guess it will need new headers etc?  I don't think we have much room in our boxes anyway!

I see there are 'standard' barometric units for use in arduino and Raspberry Pi on the net - I think one is BM180?

dave t

This will easily fit in the standard box, it is tiny