HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Nov 25, 2010, 10:58 PM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Tony,

Too bad the board is too complex for me to proto here at the workshop.

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Sign up now
to remove ads between posts
Old Nov 30, 2010, 09:29 PM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Just been looking at some of the new GPS modules ...and I'm thinking it might actually be more effective to use one and send the coordinates over the 433MHz link.

Of course, this means you'll need a GPS unit on-hand too (though one could just use the traditional yagi-tracking as well using the signal as well).

The downside of using a GPS module is that of course the cost goes up a bit and it'll be somewhat more fragile than the non-GPS.

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 05, 2010, 09:23 PM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Just received my GPS module, nice little 30x30mm unit, a bit heavy though (integrated antenna).

The "idea" here is that I can sample the plane's position periodically and then transmit it over the 433MHz band. If in the event of a crash the GPS breaks, I'll just retransmit the last known position.

Biggest downside though with all this is that it makes for a very expensive LMA.

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 10, 2010, 06:23 PM
Registered User
Tony Finn's Avatar
Weipa Queensland
Joined Jul 2007
180 Posts
Paul

just checked the thread since being on shift work, I like the way this is heading , Ive been looking for an excuse to get a hand held gps. This will make locating the model super quick. This will need to have a read out similar to the lrm on the receiver, so you could also use the read out to show a bar graph to indicate signal strength when not using the gps module, removing the need to have headphones. On second thought better keep the head phones to avoid tripping over taipan whilst not watching were we are going.

Tony
Tony Finn is offline Find More Posts by Tony Finn
Reply With Quote
Old Dec 10, 2010, 06:28 PM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Tony,

I was thinking, I could just build a GPS into the walk-around version as well, along with a compass and then I could just direct the person by working out the the relative distance/direction. Would be horribly expensive though
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 10, 2010, 09:32 PM
Registered User
Tony Finn's Avatar
Weipa Queensland
Joined Jul 2007
180 Posts
Paul

its all relative, loosing a $1000 glider every now and then gets a bit on the nose, so the investment in quality location gear is worth every cent and we all know you will look after us cost wise .

Tony
Tony Finn is offline Find More Posts by Tony Finn
Reply With Quote
Old Dec 10, 2010, 10:04 PM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Each of the options at hand have something for/against them...

1) Plain RF beacon
+ cheap, light, small
- no GPS location info, needs manual directional antenna locating

2) GPS equipped beacon
+ Know where your plane is, also can be located using 'simple' RX with tracking antenna
- More expensive, heavier, larger, more fragile

I'm thinking it'll be simpler/faster/cheaper for me to get started on the 'dumb' TX first... and maybe try design the PCB for both operations, though I'm not sure I'll succeed (yet).

The 'dumb' board is only 25x25mm, the GPS board will need to be ~32x32 (to match the GPS module and some clearance).

If anyone is interested in taking an investment gamble, I can move this along a bit quicker (right now things are tight on the cashflow), else it'll be till next year likely.

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 11, 2010, 07:32 AM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Tony,

Many thanks for that helping hand there... now, which model would you like me to develop first

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 11, 2010, 07:52 AM
Registered User
Tony Finn's Avatar
Weipa Queensland
Joined Jul 2007
180 Posts
Paul

I think the original version will be good for now as it will be the lightest and quickest to make, but dont give up on the gps version, it sounds pretty good.

Tony
Tony Finn is offline Find More Posts by Tony Finn
Reply With Quote
Old Dec 11, 2010, 08:00 AM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Tony,

I think we can have a board ready for dispatch on Monday - just hoping that the fabrication house is still open (even though it's in China they also take Christmas off for a week or so).

Paul
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 11, 2010, 08:32 AM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Here's the 3D model of what's planned...

Features:

* Integrated lipo charger (set to 50mA charge rate)
* Integrated audio alarm
* Detects signal failure from RX or power failure ( on lipo equipped versions )
* Low power consumption, enough to make TX last a couple of days on a reasonable lipo (280mAh or more)
* Low-cost version without lipo charger/integration will be buildable as well from the same board.
* Uses standard 433MHz module
* 25x25mm size.

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 11, 2010, 10:14 AM
Registered User
Stone Mountain, GA
Joined May 2007
409 Posts
Audible alarm louder than 95db?
dgfinch is offline Find More Posts by dgfinch
Reply With Quote
Old Dec 11, 2010, 05:46 PM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
dgfinch,

For the RF-tracking LMA we won't be using a super-loud audio alarm because it'll drain the battery too quickly. The small audio-alarm on the RF-tracking unit will be to help provide locating over the last 5~10m.

On the standard LMA design we certainly are looking for louder alarm options that aren't too bulky.

Paul.
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 14, 2010, 06:48 AM
PLD
Magicsmoke maker
PLD's Avatar
Australia, QLD, Charters Towers
Joined Dec 2003
17,404 Posts
Tony,

Board design will be submitted tonight for production. Crossing fingers that it'll work out

Paul
PLD is offline Find More Posts by PLD
Reply With Quote
Old Dec 14, 2010, 07:33 AM
Registered User
Tony Finn's Avatar
Weipa Queensland
Joined Jul 2007
180 Posts
Paul

Sounds good, what is the final rx set up.

Tony
Tony Finn is offline Find More Posts by Tony Finn
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Real-Time GSM/GPRS Plane Tracking or lost plane finder. for 59$ ganapati08 FPV Aircraft 12 Nov 05, 2010 11:21 AM
Discussion Radio beacon ; Lost Model finder albertocvr FPV Talk 24 Nov 07, 2007 05:15 PM
Discussion Lost plane sound beacon question. TIMN Electric Sailplanes 3 Aug 06, 2007 02:36 PM
Alert Audio lost plane beacon - finder; locator Phildc DIY Electronics 10 Jul 15, 2004 06:25 AM