HELP with letterbox that tells the user when they have mail. how cool is that!!

[sampenso08]

hi i am a yr12 student studying systems engineering and would like some help with a project that i would like to put together. i plan on making a letterbox that tells the home owner when they have mail. 

i think I'm going to do this buy using an LDR (light dependent resistor) or motion sensor (undecided) to detect movement/light when the letter box door is opened. once the LDR/motionsensor has detected movement/light, a transmitter will send a radio frequency to a receiver inside the house. from there i was going to either use a servo to mechanically flick a switch which activates a simple LED circuit to notify the user of mail, or i was told i could use a micro controller.

i only know the basics of electronics but i have put together several medium skilled kits. anyone out there that could help me would be really cool

what I'm really looking for is a list of components that i would need to purchase at a hobby store or electronics department store, and at most a quick sketch of some schematics that i could follow.

the pat that I'm struggling with the most is the whole making it wireless idea. i dont want any leads running from the letter box and into the house.

i know I'm asking for alot out of this post but it would be really awsome if someone out there could help! thank you

[goatfish]

you could just have the mailman flick a switch which is connected to a resistor and LED then to a 9v battery,just lots of cable like u didnt want lol,i know this is isnt really what you asked for but its still an easier way,just the postman does all the work(if he remebers)

[superchiku]

12 yr old studying system enginering hmmm.. isnt that just too much for ur age

but getting back i think we have replied u with ur answers using rf will be a good solution , try to search the internet for schematics

[Private Reid]

hmmmmm

didn't you already post this...

[Private Reid]

i think I'm going to do this buy using an LDR (light dependent resistor) or motion sensor (undecided)

LDR

i was told i could use a micro controller.

not recommended for this project

schematics that i could follow.

didn't i provide them...?

earlier

whole making it wireless idea

already done...i just haven't had time with the schematics

[Private Reid]

but getting back i think we have replied u with ur answers using rf will be a good solution

yer, we did

12 yr old studying system enginering hmmm.. isnt that just too much for ur age

Year 12 !

Read...

[Asellith]

just use an IR sensor to detect distance and put it at the bottom of the mail box. Whenever something is put inside the distance will change and when that happens set off the LED. Might even be better to put the sensor on the top of the box and detect downward. Might not pick up a post card but it would detect when something was inserted into the box.

[michaelsane]

Using the IR ranger is a much better way of doing it, that way it won't say you have mail when someone opens the box. 

[cooldog]

okay my idea

put a momantairy switch at the bottom of the mailbox so that when mail is put in it activates it. next go and buy a cheap remote control car. hook the switch inside the mailbox to the forward in the remote. then take the circut board in the car take off the wires leading to the motor and hoom them to a led.


so that when mail is put in the box it wirelessly sends a signal to the led to turn on

[Private Reid]

okay my idea

put a momantairy switch at the bottom of the mailbox so that when mail is put in it activates it. next go and buy a cheap remote control car. hook the switch inside the mailbox to the forward in the remote. then take the circut board in the car take off the wires leading to the motor and hoom them to a led.


so that when mail is put in the box it wirelessly sends a signal to the led to turn on

that was my idea, but i would use a ldr in the bottem of the mail box