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Need To Make A Simple Circiut into a 555 timer HELP

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Newbie level 4
Aug 31, 2007
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ok so my teacher wont accept the fact that the circuit he has told everone to use isnt even going to work... he has refuses to let us make our own but i dont realy care as it isnt reght that we all have to use the same circuit cos its easier fr him...

so if anyone has any clues of what way i would go about doing this please tell me

the curicuit needs to do this...

activated by eiter the reed or tilt switchs
then set of an alarm with Flashing led's and a Buzzer and latch on with a thyristor.

the circuit can then be turned off by a key switch to cut the power from the thyristor.

it sounds simple anough but my teacher want to have a 555 timer to do this..

dont worry about parts as i will get them myself because i dont want to be stuck with him trying to tell me bull that things like reed switchs arnt sensitive (which is complete bull as he is just trying to save him self the hassle and the department the money even tho they still charge s for the crap he gives us)

ok so if anyone can give me a hand it would be great...

if you would like more info that is fine just ask

from where are you?
you have to use 555, reed switch and tyristor?
can you use anything else?
what is your background? what lab it is?
he gave you the circuit?


Yes you can use 555 IC for the implementation.

You have to operate it in BISTABLE mode for doing this.

Try this, if it works :)

yes i can use other things but the way i made my own circuit it had a set up like this

___Switch 1____Switch 2 (NO)____Switch 3(NO)______
| ////////////////////////|_____________|___Resistor3¬ ////|
| \\\\\\\\\\\\\\\\\\\\\\\\|///////////////////////|\\\\\\\\\\\\\\\\\\\\|\\\\Resistor 4(470)
|\\\\\\\\\\\\\\\\\\\\\\\\|////////////////////// |\\\\\\\\\\\\\\\\\\\\| ///LED 1
|\\\\\\\\\\\\\\\\\\\\\\\\|////////////////////// |\\\\\\\\\\\\\\\\\\\\| ///LED 1
|\\\\\\\\\\\\\\\\\\\\\\\\|////////////////////// |\\\\\\\\\\\\\\\\\\\\| ///LED 1
|\\\\\\\\\\\\\\\\\\\\\\\\|////////////////////// |\\\\\\\\\\\\\\\\\\\\|__Thyristor
|_____________ |____________ |______________|

thats the sort of scematic im looking at lol cant upload a schem cos its on my other comp.... anyway the background to this is that it is a alarm type circut and not he did not give me the circuit he told us to use a prefabricated one and to customise it but the problem is that the picture of the pcb he gave use does not match the schematic or the design that we also got so it theriticly doesnt work and we have all said this but he will not answer the question "will this circuit even work" so i am following my gut instinct and im going to make my own with out his help as he him self is realy only out of college ......

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