DT project help

[jakeDT]

Hi i am study A level dt at school and need some help. I need to make a circuit that will light up LED's when it is dark. The circuit must be cheap and run off a 12v and under power supply. Also i will need to know where to get the parts from thanks

 

[birdman0_o]

You haven't filled out your location, how do we know where you need to get parts from. This can be a simple circuit if you use an LDR as a voltage divider accross the base of a transistor.

 

[audioguru]

What is "study A level dt"??
When I went to school the levels were numbered grades. Grade 7 to grade 13 was high school.

 

[JimB]

What is "study A level dt"??
When I went to school the levels were numbered grades. Grade 7 to grade 13 was high school.

At a quick guess the OP is in the UK, so I guess that you would not be familiar with "A level" AG. A level is a series of exams generally taken at the age of 17 or so, prior to leaving (high) school and maybe going on to university or w.h.y. At another quick guess, DT is Design and Technology.I will not address the subject of the project this time, but I will say to Jake (if he re-appears), please make your posts a bit clearer and less ambiguous, this is an international forum and many of the experts here will not be familiar with UK school culture. Come to think of it most of us oldies in the UK are not familiar either! Also, it is a good idea to fill in your location in the registration area, this often helps in sorting problems. OK, judging from the time the original post was made it may have been done on a school computer where the party line would be to never reveal where you are lest the boogie man comes and gets you. However putting UK or the nearest major town/city cant hurt anyone.JimB

 

[jakeDT]

Hi guys sorry about that yes im from the UK and i am still at school. Basically i just want to make a circuit that will turn on LED's when it is dark and it will run off a small 9v battery or some AA's. I would also like to put a variable resistor in the circuit to control how dark it needs to be for the LED's to come on. Would this be hard? as i say im still at school so could u explain as simply as possible as i am new to electronics. Thanks

 

[birdman0_o]

First post on this thread :
Link

 

[JimB]

I have had a look at the circuit suggested by Birdman.

It is a poor circuit, but will work ok within its limitations.
I have edited the circuit a little bit as shown below to make it light an LED rather than operate a relay.

JimB

 

[birdman0_o]

Thanks for the time put in Jim, I just wanted to quickly introduce him to the circuit and I had the link available, let's wait and see what he thinks of it.

 

[jakeDT]

Hi guys thanks for all the help that looks really good i recon i could make that where could i get those parts would it be best to get them anywhere off the internet? thank you