proximity circuit

shumaila

hey everyone
greetings
i am first year student of electronics at ned khi and i am asked t make a proximity circuit using LDR
can any one help me make a simple circuit .... there are bonus mrks for smallest circuit ... i can not find a schematic

kwinn

Did you try googling "LDR proximity sensor schematic"? I got "About 1,840,000 results" when I did.

Clock Loop

Well lets go ahead and make this an official project.


And ...Considering its your first year....

Step 1: Purchase a BOE bot kit.
http://www.parallax.com/product/28832

Step 2: purchase 5 transistors(in case you kill some, really you only need 2) http://www.parallax.com/product/500-00001

Step 3: purchase an LDR. http://www.parallax.com/product/350-00009

Step 3: look at this circuit.

The boe bot kit contains the breadboard, resistors, jumper wires(you can use this without the BOE BOT, (which has power built in) you can have it portable with a 9v battery, or 3 AA's(you supply)
(the boe bot shows you how to make a proximity circuit and intelligent proximity decisions for the "future classes", HINT HINT.

The LDR circuit above can be built on the breadboard, (no need to include the breadboard circuitry into the circuitry of the LDR project. you are just using it as a power supply, and breadboard. (you will use the boe bot and other parts later in school, and for fun)

If you still have trouble with the preset resistor and led resistor values, let us know.

Clock Loop

What can a boebot do with a (LDR)photoresistor? (it uses it to calibrate the level of light in the room)

http://forums.parallax.com/showthread.php/141426-Daylight-Sensor?highlight=photoresistor

http://forums.parallax.com/showthread.php/128920-Photoresistor-controlled-light-switch?highlight=photoresistor

http://forums.parallax.com/showthread.php/140672-Photo-Resistor-Resistor-value?highlight=photoresistor

shumaila

Thankyou for your response but i am facing alot of trouble with values of resistors