annoyed :)

[madmikejt12]

ive done a realy simple circuit to wind my mum up just playing around with a cds cell lol, i connected a battery, Cds cell and a buzzer in series and fitted it into a 4AA battery holder (one side for batteries, the other for buzzer+wires, the Cds cell is "lose" so i can move it) i placed it under her light, so when she turns it on its going to give an annoying bzzzzzzz , she has an upward facing light shade so it is hidden, also i posisioned it so when you turn the light on, you can't see the shaddow lol :twisted:

 

[Dr.EM]

Pure evil :lol:

On the projects I think theres a similar project that buzzes when the lights are switched off

 

[madmikejt12]

yeh i know, im gunna do that aswell put that in my sisters room :twisted:
ive ordered most of the parts for it i was buying parts for my model railway signal and i thaught why not?? :lol:

 

[zachtheterrible]

Pure evil :lol:

On the projects I think theres a similar project that buzzes when the lights are switched off

Thats my circuit :lol:
It even delays 10 seconds after the lights go off :twisted:

 

[Optikon]

Pure evil :lol:

On the projects I think theres a similar project that buzzes when the lights are switched off

Thats my circuit :lol:
It even delays 10 seconds after the lights go off :twisted:

The 10 seconds is a nice touch Zach! Just when they get comfortable with silence, it kicks in.

To be particularly nasty, how about a random delay anywhere from 10seconds to 1 minute. Oh, and hide it in the ceiling light.

 

[madmikejt12]

i was thinking about that, wasnt sure if it could be done, you could also try to make it so at first there is a minuit gap, then 40 seconds, then 30, 20, 10 ,5 1,1, 1, 1, and then a minuit (after the 4th 1 second gap, they will think it has stopped and then when it comes on after a minuit again....... :twisted: lol

 

[Someone Electro]

That wod be prety easy to do whith an PIC.But wod be prety complicated to do analog or whith logic gates.

 

[madmikejt12]

oh yeh, it went well, my sister went in, turned the light on and it buzzed, she turned it off and on again... buzzed again she sed oh s**** and walked out, my mum came up and turned it on, she screamed coz she thaught it was a wasp or something, she turned the light off.. buzz stoped.. turned it on and it buzzed again, she was about to phone gordan (the electrician that does all our plumbing, DIY and electrical jobs) i had to go in and stop her!!! lol

 

[Someone Electro]

LOL :lol: :lol: :lol:

That must of ben fun to watch.

 

[mstechca]

That wod be prety easy to do whith an PIC.But wod be prety complicated to do analog or whith logic gates.

A resistor and capacitor determine frequency. Change the value of one of those components and then the time changes.

 

[zachtheterrible]

Electro, I'm still trying to get my PIC programmer to work, so when I do, and get a little knowledge on how to program PICs, I'm going to do just that :twisted:

 

[Someone Electro]

It can be somtines compicted to get purly random numbers.The easyest way is the pusedo number.

There is also an advantege since PICs use realy realy litle power.Especaly wen run at 32Khz.Even at full power(20Mhz) the PIC will consume les than 2mA.

And an Piezo speaker.It may seem silent but wen you are in bed you get used to the silence and hear it prety loud.

The one whith the PIC i built maked such buzing sounds like a fly.

 

[Roboticinfo]

You know what sfunny the Tv remote blocker, it sends a series of IR signals and doesn't let the tv remote work while holding the switch.
Simple circuit but fun to watch dad try to use the remote.

:lol:

 

[Someone Electro]

Ive seean those.
They flod the IR reciver.

 

[zachtheterrible]

Hee hee, ive done that one.

I used a 555 to modulate an IR LED @ 25khz. This was actually for a system that I made for my friend that beeps when someone walks through the door (IR sensor on the other side), but it worked fine for the TV.

 

[Agent 009]

What's a Cds cell :?:

 

[Someone Electro]

Its a photo resistor. It changes resistance acording to the light falling on it.

 

[madmikejt12]

it is similar to a LDR, does it work in the same way or the oposite way? im not quite sure

 

[Someone Electro]

I think Cds means Cardium sulfate wich is i thnk used in these things.
A LDR is Light Dependent Resistor.

There are other ways of detecting light like an photo didoe,photo transistor,LED,solar cell...

 

[madmikejt12]

yes but a Cds wired up to just a battery and a light/ buzzer will come on ONLY when there is light, is it the same for an LDR?

also, instead of the 50k pot used in this circuit, could i use a 10k? what would be the diference?

It's just that i broke my 50k



Edit: oops sorry, thaught it was in the nightlight thread, i got confused because both threads contain the word Cds cell in them lol