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n/a
DELETED (Inactive)
4 Posts |
 Posted - Feb 08 2004 : 3:38:04 PM
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Well I don't know what you are all going to say about this one. Just don't call me cheap.
I just finished looking through the entire forum for some ideas and info.
I'm designing a cheap car alarm for a friend. Just somthing that can be activated and de-activated using a remote (radio or IR doesn't matter).
I have a system of relays that are going to be used for controlling different things such as a flashing LED when the alarm is activated. Headlight flashing, horn honking, etc. maybe even include something on the starter so it can be killed so the "thief" cannot start the vehicle.
I do however need some ideas for the remote... I might just use an old RC toy for the transmitter and receiver. This will drive a small circuit that will run a latching relay to keep the alarm on until something is done to kill the system.
Here's the problem... I know next to nothing about all of this and I will probably end up making something that doesnt work at all... Any input from anyone here would be appreciated. Even critisism is ok for me. I just what to know what you all think. I will have the schematics up on my site soon enough... As soon as i refine them a little bit. At least so i can read the schematics and understand them myself.
Ok well thx in advance for any help or avice.
Tha_Bommer
alias Alexander Arsenault
tha_bommer@hotmail.com
http://www.bommer.dynu.com |
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Feb 09 2004 : 4:39:13 PM
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There's an IR Remote schematic in the circuits section of this site.
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YS
Nobel Prize Winner
USA
1132 Posts |
Posted - Feb 09 2004 : 7:35:13 PM
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How do you provide security?
with any standard frequency range, be it IR or radio, if you do not apply some coding everybody can disengage the alarm. Radio things are much cheaper to buy than to make. For example, you may buy RC model for $10 or even less, throw away the plastic, and use transmitter and receiver, just adding encoder/decoder. It might be a tone generator on the transmitter side and NE567-based decoder on the receiver side, take both from schematic Aaron just mentioned; or make a pulse sequence.. so, think of combining two or more well-known things into unusual combination. You may use two tone generators at different frequencies and two tone decoders, with AND gate to combine outputs. Or, the cheapest: consider magnetic-controlled contact (like in reed relay) put under rubber strip on the driver's window. Having a small magnet in your hand or on the bracelet, you can engage it. Not a big distance though. And so on..
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BEatonNo1
Nobel Prize Winner
USA
1133 Posts |
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ecm
Apprentice
Canada
89 Posts |
Posted - Feb 12 2004 : 8:31:38 PM
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for my alarm control i use the keyless entry of the car to activate a latching relay .the alarm i built it my self .
to do or not to do |
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Cheap Car Alarm
