I propose a...

[normiss 803]

You're gonna need one hell of an extension cord.

[rwieder 0]

It's internally powered, no worries.

Best-
Richard

[normiss 803]

Until it needs recharging, right?

[billvon 2,998]

Where will you fit the laptop in your rig?

[normiss 803]

You're jumping ahead of the class.
Again.

[Andy9o8 2]

billvon

Where will you fit the laptop in your rig?

Reserve trays tend to be very snug fits these days. Just wedge it in there. Guaranteed not to extract.

[Divalent 137]

nigel99

The investment to develop a system is simply not worth it.

I've been toying with developing a proprietary system to recover main parachutes for a couple of years now (it's not technically difficult). Coupling a GPS device to a very low power transceiver is a piece of cake, and once you are off mobile phone technology a 2-3 year battery life from a small lithium is easy. Range would be about half a mile on a typical dz without any real problems.

The problem is that to make it worth doing in the first place, it is going to cost circa $100 per setup and I don't see people bothering to spend that money in enough volume to make it viable...

Several companies are working on, or actually have, devices that might do the job as a main recovery option for under $100. See some of the links in this thread:

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4512148

I'd be interested in your thoughts on what is they are developing. A more limited range unit is available now (~100 ft; and about the size of a triple thick US 25 cent coin), and one company hopes to have a 1/2 mile version out by the end of the year (but it's larger).

[nigel99 489]

Divalent

***The investment to develop a system is simply not worth it.

I've been toying with developing a proprietary system to recover main parachutes for a couple of years now (it's not technically difficult). Coupling a GPS device to a very low power transceiver is a piece of cake, and once you are off mobile phone technology a 2-3 year battery life from a small lithium is easy. Range would be about half a mile on a typical dz without any real problems.

The problem is that to make it worth doing in the first place, it is going to cost circa $100 per setup and I don't see people bothering to spend that money in enough volume to make it viable...

Several companies are working on, or actually have, devices that might do the job as a main recovery option for under $100. See some of the links in this thread:

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4512148

I'd be interested in your thoughts on what is they are developing. A more limited range unit is available now (~100 ft; and about the size of a triple thick US 25 cent coin), and one company hopes to have a 1/2 mile version out by the end of the year (but it's larger).

Hi Peter,

The core requirements that I see are as follows:

1) Cost of less than US$100
2) "True" radio range outdoors of approximately 0.5miles
3) Battery life equivalent to an Audible so a few hundred jumps or about 1 year.
4) Ability to differentiate between units
5) Timely search function.

The Blutracker device is highly unlikely to have a genuine 0.5mile range. Most claims of that nature are based on the Friis transmission equation and are high school physics level. You need to account for fading margin and other effects, unfortunately due to marketing pressures nearly everyone uses the simplified Friis equation, so to really get 0.5miles, you'll want to see 2-3 miles advertised.

Secondly recharging every 2 months, is a headache and I'm pretty sure most people would simply forget to charge it after the first couple of attempts, meaning that when you need it, its flat.

Technically how I would do it:
- Use the higher powered ISM bands (There are usually between 870 and 930MHz, depending on where you are in the world)
- You would have a receiver unit (USB dongle perhaps?) that would respond to the rig based unit, so technically a transceiver.
- Unit on the rig unit 'pings' once every 5 minutes.
- if the rig unit receives a message, it will then actuate the GPS receiver and transmit the location once a minute for about 10 minutes then default to the original state.
- possible have an audible beeper on the unit that can be activated remotely.

The above would need the rig unit to be in sleep mode for the vast majority of the time, this gives you the years of battery life, that things like Ultra low power Blutooth can't. The big issues are regulatory compliance - if you make a unit for the USA it won't be legal in Europe and so you have issues with global travel.

Cost wise you would need circa $100k for the development and then you would need to manufacture at least 1000 units to get a reasonable built cost. So you end up spending $250-500k for a really small market. Lets not forget that attaching stuff to mains, risers or freebags is a whole lot of safety considerations and rigging that also needs to be dealt with.

In short as soon as you introduce a radio transmitter and you want to stay legal it costs alot of money.

One really simple option would be to have something fitted to a riser that has the cutaway cable fed through it. When you cut away it starts beeping loudly every 10-20 seconds. The most complicated part of that is ensuring you don't mess with the cutaway system, and the benefit is that the battery would last for years as it is off until activated.

Experienced jumper - someone who has made mistakes more often than I have and lived.

[potatoman 0]

A cellular phone sim card, can be triangularly traced without it having a a power source, and they are small. Problem if it is in water though.

The only problem is, you need the company that owns the nearby transmitting towers to play with.

You have the right to your opinion, and I have the right to tell you how Fu***** stupid it is.
Davelepka - "This isn't an x-box, or a Chevy truck forum"
Whatever you do, don't listen to ChrisD.

[nigel99 489]

potatoman

A cellular phone sim card, can be triangularly traced without it having a a power source, and they are small. Problem if it is in water though.

The only problem is, you need the company that owns the nearby transmitting towers to play with.

That's not correct, did you get that from a Bond movie

You can triangulate a mobile phone, provided it is on, but it doesn't need to be in a call. You certainly need more than the SIM, as you need the air interface (radio)

Experienced jumper - someone who has made mistakes more often than I have and lived.

[airtwardo 7]

GooniesKid

...type of Lo-Jack system for rigs.
There must be a way to fit a small/lightweight Lo-Jack system on a rig right?
All these recent reports of stolen rigs...

I bet the most likely culprits of stolen rigs are the 1 time visitors and NOT the veteran weekend warriors.

I know...how about just keeping an eye on your rig?

~ If you choke a Smurf, what color does it turn? ~