Messages

91

General Discussion / Re: Enhancement Requests

« on: July 11, 2016, 09:52:09 am »

Just a thought to throw the idea into the mixer..

Making use of the Infrared receiver on the SDR dongle. ..volume changes or anything else?


http://www.rtl-sdr.com/making-use-of-the-infrared-led-on-rtl-sdr-dongles/

My SDR dongle came with a small credit card IR remote..

92

General Discussion / Re: What's the status of FLARM ?

« on: June 23, 2016, 12:38:40 pm »

What frequency does FLARM Tx/Rx on?  Is this receivable by either the RTL dongle or Bridge unit?
If this is the case then could PAW simply, without decoding, detect the presence of the signal and give some simple warning of gliders in the vicinity?

93

Technical Support / Re: New Licence

« on: June 23, 2016, 12:29:12 pm »

The RTL dongles are renowned for their hot running..

http://www.rtl-sdr.com/rtl-sdr-heat-dissipation-as-seen-by-a-thermal-camera/ 

94

General Discussion / Re: How to stop transmissions

« on: June 19, 2016, 05:39:41 pm »

what if at some point in the future there was a very lightweight/lowpower version of PAW for a very very lightweight A/C

Excellent Idea!  Every drone should be fitted with one!

95

Technical Support / Re: New User - Aerial Problems

« on: June 18, 2016, 11:09:31 am »

If you did want to leave the PAW antenna disconnected then you must terminate the output from the bridge with something like this..

http://www.ebay.co.uk/itm/1pcs-SMA-Plug-RF-Coaxial-Termination-Dummy-Loads-1-2-W-0-5-watt-DC-2-5GHz-50-Ohm-/322065885392?hash=item4afc9f68d0:g:4z0AAOSwQJhUbwtx

96

Technical Support / Re: Mode C

« on: June 18, 2016, 07:43:08 am »

I would have thought that by the law of 'Square the RF output power to double the range', any received replies from ones own transponder, even from outside to inside the AC would be a significant order of magnitude higher than anything received from other aircraft and fairly able to eliminate.

This is how the ZAON MRX PCAS works to eliminate 'own aircraft' A friend gave me his to look at as it was only seeing his own aircraft and nothing else. It turned out that the antenna connecter had broken at the pcb, so the device could only pick up the strong replies from the host aircraft (C172) actually on a 2mm track on the PCB of the device! and , seeing this now weaker signal, alerted on it.

Is PAW able to collect 'strength of replies' information from the DVB-T receiver to collect logs from willing volunteers?

97

General Discussion / Re: Tuning the DVB Antenna for 1090MHz Specific reception

« on: June 12, 2016, 05:43:26 pm »

Interestingly (and very timely) these two videos have appeared on Youtube looking at the supplied DVB-T antennas..

https://www.youtube.com/watch?v=Rb_GzhvVTQ4  ..for the techies amongst us. Good though there is resonance at around 540MHz so also at 1090! the cable probably is quite lossy then though.

https://www.youtube.com/watch?v=3RsazRx4cxE  ..shows a teardown of the antennas much as I did earlier in the thread.

98

Technical Support / Re: SOLVED! - Pi 2 Wifi problems with a Nexus 7

« on: June 10, 2016, 09:00:00 pm »

Forgot to mention, I was already running 20160530 which I had previously tested as fully stable at home.

99

Technical Support / Re: SOLVED! - Pi 2 Wifi problems with a Nexus 7

« on: June 10, 2016, 08:51:03 pm »

Interesting you should suggest that Paul, I flew with my now Pi 2 PAW (Bridge not arrived yet) and my N7 on Wednesday.

On the outbound flight I was P1. The PAW was on top of the coaming on the other side of the cockpit, no more than a metre away from the N7. The connection was rock solid for the whole hours flight (although we did receive some odd mute lifting RFI on Lakenheath Radar's VHF frequency 128.9 while crossing their overhead ..perhaps it was the multiple F16's doing circuits beneath us!  )

On the return, I was passenger, with PAW and N7 some 200mm apart and the connection to Skydemon simply refused to stay up for more than 30 seconds in most instances. Looks like we possibly have some internal emissions problems in our 70's cockpit. Next time I'll try switching off the Bendix King DME which is most likely not WIFI compliant!

100

General Discussion / Re: Tuning the DVB Antenna for 1090MHz Specific reception

« on: June 10, 2016, 11:36:19 am »

Still not happy with the D-TV antenna flapping about, especially weightless with the magnet removed, I tried for a neater solution and I think it's worked exceptionally well.

I found that a standard Wifi router antenna (£3 on Ebay) pulls apart so you can get to the monopole inside. I cut this to only just over 17mm in length which is 1/16 lambda at 1090Mhz.  I then cut down the top cover of the antenna and chamfered back a spigot so it would refit into the base....



I now have a stubby antenna of less than 3 inches in length connected to a RP-SMA to MCX pigtail (RP= Reverse polarity, handy so it can't be mixed up with the PAW antenna). So, Where to mount it? I thought maybe it could fit somewhere on the, case but I haven't received my Bridge yet so didn't want to commit. Searched around for something everyone should have around the house, then it struck me that there's already a free stable mounting point on the Pi...



Finally, sourced a pigtail with a right angle MCX (bit more brass too so aids cooling of the hot running ADSB dongle!). I think the final solution is fairly neat, even more so when I get some black tyraps! and sturdy..



I thought the 1/16 wave antenna would also have the benefit of reducing the reception range of the ADSB but I noticed in the aircraft the other day, It was still picking up targets over 200km away!

Vic

101

Technical Support / Re: Downloading New Software Releases;

« on: June 07, 2016, 11:59:35 am »

Hi Vic,
Actually you can still install to test your WiFi issue, because you can see if you can connect to the home webpage
http://192.168.1.1
if you get a connection, then you know the reversion to WiFi Mode-B has solved your issue

Thx
Lee

Thanks Lee, that's much more stable, rock solid through 2 walls in the house!

NOW! when can I buy a bridge!!??   

**EDIT** Disregard, I see they're up on the  shop now! 

102

Technical Support / Re: Downloading New Software Releases;

« on: June 06, 2016, 11:40:20 pm »

Please note also, this release MUST have a PilotAware Bridge present in order to work correctly.

Ah! so no chance of me testing to see if my Nexus 7's connection is now stable before buying a bridge then? 

103

Technical Support / Re: Pi 2 Wifi problems with a Nexus 7

« on: June 03, 2016, 08:43:05 pm »

Lee, I am running v 20160511


Vic

104

Technical Support / Re: Pi 2 Wifi problems with a Nexus 7

« on: June 03, 2016, 11:06:30 am »

Bit more information on this which I am still experiencing to a degree on the N7 which definitely appears to be the bad boy in all of this.

I ran the Pilotaware on a Pi 3 official power supply following the previous suggestions.

The N7 is still reticent to connect to the PA WAP but eventually does so after about 30 seconds 'awaiting IP allocation' or similar. Accessing the web server part of the PAW is very slow in responding. The Skydemon connection appeared to hold up well though. 

If then, with the N7 still connected, I connect with my phone, the N7 disconnects in Skydemon (wifi stays connected though), unable to reconnect to 'FLARM', the web server is inaccessible and the phone's use on Skydemon with Flarm is also flaky with no web server response.  The only way to resolve this is to reset the PAW.

On resetting the PAW, the phone connects fine and I left Skydemon running stable for an hour seeing ADSB targets. As soon as I try connecting the N7 though, the phone is dropped out of Nav in skydemon.

I believe it should be no problem at all connecting multiple devices to the PAW?  Hope this helps anyone with diagnostics or maybe the next release will solve the issue.

Vic

105

General Discussion / Tuning the DVB Antenna for 1090MHz Specific reception

« on: May 28, 2016, 04:45:25 pm »

During my unsuccessful test flight with my PAW (ADSB only currently) due to connection issues with my Nexus 7, I realised that the DVB antenna was too long to comfortably mount on the coaming of our 172 under the rake of the windscreen. It ended up laying on its side at the base of the screen.

The DVB Antenna which comes with these USB TV tuners is a fairly basic device, It has a quarter wave tuned length to pick up broadcast stations in the 450MHz to 700 MHz band roughly. The screw off monopole top is around 12cm long. The ideal quarter wave resonant length at 1090Mhz is calculated at 68.9mm

I have a small telescopic antenna that can screw onto the DVB-T antenna base. It varies from 60mm up to around 200mm. I was using this on the PAW to find I was getting the best results with it at it's shortest length. While I was experimenting with the PAW in the garden and the antenna up on a fence post, I realised that even without the aerial present, just the base, I was still picking up aircraft around 50NM away! This alone is actually good enough for PAW use!


Antenna base with monopole removed



The exposed coaxial centre is, in itself, an antenna of around 19mm in length.


 So, to complete the construction of a properly tuned ADSB antenna, I cut down the top whip to 50mm in length, gently twisting off the end protector and gluing it back on the new (very sharp) end.

Results of ADSB reception is improved over the original antenna length, seeing targets out to 175Km in my fairly overlooked garden.

Tuned antenna


I know this sort of sensitivity is way over the top in terms of PAW usage but having an antenna tuned to the correct specific frequency is a good start in eliminating other unwanted frequencies, specifically in the natural case of this DVB antenna in its unmodified state, strong TV broadcasts and phone masts!

I now have a much shorter 1090MHz specific antenna which can sit easily on top of the pilotaware unit itself under the windscreen . I also took the opportunity to shorten the cable from the MCX plug as its easy from the antenna end of the cable.  The braiding isn't clamped under the metal disk anymore, but soldered to it aiding with strain releif.

So, my tip is to unscrew the top whip of the DVB antenna and cut it to a total of 50mm in length. Hope someone finds this useful!