Author Topic: Barometric Pressure Way-off ?  (Read 13347 times)

JCurtis

Re: Barometric Pressure Way-off ?
« Reply #15 on: December 14, 2016, 06:25:26 pm »
The barometers on the old Harkwood ARF boards, which I still have, were both accurate to significantly better than 1mb.

I used MPL3115A2 modules from NXP, I presume the Bridge uses the same, they are very accurate.  Unless you vapour phase solder them, then some of the fluid can condensate inside the sensor and may cause issues down the line.
Designer and maker of charge4.harkwood.co.uk, smart universal USB chargers designed for aviation.  USB Type-A and USB-C power without the RF interference. Approved for EASA installs under CS-STAN too.

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #16 on: December 15, 2016, 01:55:34 pm »
Superficially it does look like the same barometric sensor and I note that the specified accuracy is circa 1ft, so this one being around 70ft out is something of a surprise.
John
G-JONL, Sportcruiser, Carlisle

Easy Cruising

Re: Barometric Pressure Way-off ?
« Reply #17 on: December 18, 2016, 07:29:39 am »
fyi .. I created a new post called "Feedback: PAW pressure and Mode C/S" , to give feedback after testing the pressure as suggested in this post.

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #18 on: December 18, 2016, 10:40:10 am »
My PAW has now been on for ten days just sitting at home watching the world fly by. Interestingly, the pressure sensor is slowly drifting into spec - it's now just about 1mb out, which is insignificant for the intended application.

Still yet to receive a single P3i transmission but PAW is thin on the ground as yet, up here in the frozen north.
John
G-JONL, Sportcruiser, Carlisle

exfirepro

Re: Barometric Pressure Way-off ?
« Reply #19 on: December 18, 2016, 10:51:39 am »
John,

You should try a flight up my way (East Fortune) we now have a small but solid core (and growing) of aircraft 'PAW operational' here and also a few out of Fife (Glenrothes) and Perth. Let me know if/when you can visit and I'll arrange to meet up.

Regards

Peter

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #20 on: December 18, 2016, 11:14:16 am »
Hi Peter,

I've flown past East Fortune numerous times, en-route Fife/Perth/Dundee/other places north, but never actually landed there. I should do that some time!
John
G-JONL, Sportcruiser, Carlisle

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #21 on: December 18, 2016, 03:01:51 pm »
Ahha, broken my duck! Something with PAW flew past a while ago and I picked up 79 P3I transmissions. Wonder who it was?
John
G-JONL, Sportcruiser, Carlisle

Ian Melville

Re: Barometric Pressure Way-off ?
« Reply #22 on: December 18, 2016, 05:47:47 pm »
The log will tell you

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #23 on: December 18, 2016, 06:18:40 pm »
Yes, I thought about that. I need to RTFM to find out how all that works. I guess I needed to enable some of the Log Interface Messages options in config but I hadn't done that, as most are too cryptic for me to immediately grasp what they do. The settings don't seem to save either. I'd better go and look out that manual... there's only so much one can discover by doing the blokey thing of not reading it.
John
G-JONL, Sportcruiser, Carlisle

exfirepro

Re: Barometric Pressure Way-off ?
« Reply #24 on: December 18, 2016, 07:55:48 pm »
John,

It's not critical to preset anything. Just plug a USB stick into your PAW while it is running. If all your USBs are being used you can unplug anything except the WiFi (PAW doesn't like it if you unplug the WiFi when it's running). Also don't use any port you have configured for ADSB out or FLARM in - or PAW can do things you might not like with any data on your stick.

Log in to 192.168.1.1. Go to the tracks page, Sync tracks you want (or all) onto your stick (PAW automatically sets up a PilotAware folder with a Tracks folder inside it). This only takes seconds - indicated by the progress bar moving across the screen. Remove your stick and transfer the track files to a PC or laptop. You can then open and read them with Notepad or Wordpad.

Look for entries at or near the time you had the contact. IIRC P3i entries will have the callsign enclosed in # 'brackets' unless the Group ID has been changed from the standard 'PAWGRP'.

Regards

Peter

Edit: John - just noticed over on another thread that you have already worked most of this out, but it might help someone else, so I will leave it on.
« Last Edit: December 18, 2016, 08:00:21 pm by exfirepro »

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #25 on: December 18, 2016, 08:50:46 pm »
Thanks Peter. Having finally got the track data onto my memory stick I've been playing around with the data and have discovered that it was one G-CCEJ, presumably of this parish, who buzzed the place at around 14:30 today, getting within a few hundred metres, so I think he must have seen the PAW alert and gone looking for the source! He would have found a white cottage on top of a hill with some VERY big aerials, none of which are anything to do with PAW. I think the RAF has it programmed in as a VRP.

I'm cracking this slowly...!

EDIT: I see that G-CCEJ is indeed in the PAW map and I have just added myself back there after my hiatus.
« Last Edit: December 18, 2016, 08:55:28 pm by The Westmorland Flyer »
John
G-JONL, Sportcruiser, Carlisle

Keithvinning

Re: Barometric Pressure Way-off ?
« Reply #26 on: December 19, 2016, 05:52:43 pm »
Hi John
Have you undertaken a permanent installation on the SC. Quite a few SC's have. It makes a tremendous difference on range
I have done it on G-MOOV
Keith

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #27 on: December 19, 2016, 06:06:03 pm »
Not yet, Keith. It's in my to-do list over the next few weeks, together with changing out my transponder for one that squitters appropriately. Why do I always seem to be doing maintenance work on my aircraft in the middle of winter?!

I'd be interested to know where you put the various antennas. I was thinking that the front of the engine bay might be a good place for the PAW antenna. I'd like to avoid taping it to the hatch if possible. The GPS and ADS-B antennas are rather less critical of course. I was thinking of running all the cables back to behind the seats, via the tubes under the central console and then putting the hardware there, out of the way. What did you do? If you'd prefer to take this to PM then that's fine.
John
G-JONL, Sportcruiser, Carlisle

Ian Melville

Re: Barometric Pressure Way-off ?
« Reply #28 on: December 19, 2016, 08:11:00 pm »
Quote
Why do I always seem to be doing maintenance work on my aircraft in the middle of winter?!
So it won't eat into summer flying time ;) But it is a pain if the hangar/shed is cold and dark

The Westmorland Flyer

Re: Barometric Pressure Way-off ?
« Reply #29 on: December 19, 2016, 08:19:02 pm »
Quote
Why do I always seem to be doing maintenance work on my aircraft in the middle of winter?!
So it won't eat into summer flying time ;) But it is a pain if the hangar/shed is cold and dark
Got it in one!
John
G-JONL, Sportcruiser, Carlisle