Hey Forum members,

I have recently gotten into armature rocket propulsion research (like Hybrids, Liquids and chemical acid based oxidizer motors) and need a means to safely fire them from 250m plus (A CATO from a MYROL rocket isn't something to be laughed at), but as well from firing the actual rocket there is ground support gear that needs to be remotely looked after such as fill stations and heaters ect. probably 4 things in the end need to be initiated

I am looking into a WIreless/radio system

However I need this to be safe and as I have stated I don't want to be any ware near a tube full of well, explosives.
The risks of things going wrong is to high and thus wanna get away from them.

I was thinking of 3 possible ways
1. I could use simple 433mhz radio module and then use an encoder and decoder system...

2. I could get to micro controller stamps (basic stamp, picaxe, arduino)
then inter face them with an XBEE rf module. this way I could have the Transceiver send a string to the receiving unit and it would then match and let commands be sent or actively refused which eliminates my stray signal problem. However that's eaisley over $200 and i don't have the money to do something like that.

3. The jaycar sms I/O controller this is perfect aside from 1 thing.
The Australian mobile telecommunications backbone isn't that good and optimality I would like to be in the middle of the bush away from any people that could accidentally walk inline (I don't want to put anybody in danger!) I just want the tests to be performed at remote safe locations.


I could relay use the help of someone to help me with the schematics as Im a Chemist not an electrical enginear and don't have a massive knowledge on the subject. but I understand the basics and moderate stuff ( I can follow a IC's data sheet)

Cheers,
Kwinchee

Thanks for reading

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\"What it was, what it always will be\"

 

Check out this ebay store-
http://stores.ebay.com/e-MadeinCHN_W...Q3amesstQQtZkm
You can select momentary, or latching control, and it is all done thru coded digital signals- only your transmitter operates your receiver.
Best of luck with your rocketry- Play safe!
John

 

I strongly recommend that you find a source of surplus cable, buy yourself 250m of a multiple conductor type, say 24 or 26 AWG, with perhaps 4 or 6 pairs of wire and string this from your control bunker to your launch site. This is far safer and simpler than using wireless. A new cable of this length might cost US$100 but you might find surplus or used cable for much less. Save your time and energy for your rocket motor research, don't spend it on a project that has little to do with rockets.

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RadioRon

 

Although hard wiring is "simpler", without knowing what types of ignitors, initiators, or activators are in use at the launchpad, wire may be susceptable to random signals (false fire). It's a large antenna.
If you encode the signals on the wire, might as well go wireless. You'll need some large batteries and large cable to power 250 yds of cable too.
Let us know what your voltage/current is needed at the pad, and we can compute how large a power supply and wire size you'll need to hard wire.
John

 

I am firing the rocket via a pyrogen bridgless ematch which eaisley needs 12v @ 2 amps

But See I could just use relays and have a big sealed Pb battary on the receiving end.

But the made in china system is relay perfect for my situation!

Thanks for your ideas

If any body has any good digital circuit ideas using like wireless data modems give me a yell

__________________
\"What it was, what it always will be\"

 

I would go for hardwire I bet NASA does the same

make sure your batery case is sturdy enough to take a blast
just an idea
try a laser pointer and a IR cell who is sensative for that spectrum but with a small beam it's dificult to get the alingment right (you will need binoculars)

 

A laser pointer at 250 Meters? For ignition? Sounds risky if not very difficult.
Doubt if the original poster has a NASA budget. Yeah, I'd put the battery and receiver below ground level, and protected.