Project: Night Buzzer - Page 2 - Electronic Circuits Projects Diagrams Free

zachtheterrible · 14th April 2005, 02:46 AM

Im gonna have to do that someday. Not now, as you may have read ive got a rather large alarm project that im working on.

Someone Electro · 14th April 2005, 04:45 AM

Il try to make it since i have an PIC16F88,programer,5v regulator...

I suck together an perogramer out of a cumple of transistors and resitors and its on the LPT.The down side is i have to have an external power suply of 13v an 5V

anyway what do ou know about PICs?

Hmm...meaby an phototransistor on ADC and an piezo speker

Someone Electro · 14th April 2005, 06:24 PM

i got the hardware working but the damn phottotrasistos has 15° angle so it can only sence light of objects that is exsactly pinted it to (this wod be only useful in a shoting game there you have to point the "gun" directly in an LED)
I just cant find the photoresistor of mine wich has an 130° angle

Now i have to make the program (10 bit output from the ADC is casing me headaces becose 10 bit is harder to work whith than 8 bit )

First il try to make it work like the "analog original" works so your circuit will have an digital brother but then il try to complicate it a bit like the thiming thing.

wod be also cool to conect an microphone in but in not going to do that.

It also has an super small curent draw.Wean slilent it drawn 0.04 mA an that wod run on my litium cell for about 2 years continuestly by runing it at 34kHz(you beter not run it for that long since the guy may end up by the psycaetrist and if he finds out you cod end up in a hospital)
you can see an slight delay on the leds since it has to divide an 10 bit number whith 120 on such an low freqency (but i goes super smoth wen run at 10Mhz but then it draws 1.3mA)

how much dose your circuit draw?

zachtheterrible · 15th April 2005, 01:44 AM

hey electro, thats a nice bit of information, glad youre keeping me informed.

I havent even checked what my circuit draws. at the time i built it, my ammeter was burned out. Dont ask about the stupidity that caused that.

What do I know about pics? Not a bloody thing. i am really going to investigate them though, i know there is so much that can be done with them.

Quote:

wod be also cool to conect an microphone in but in not going to do that.

what do you mean by that?

Quote:

i got the hardware working but the damn phottotrasistos has 15° angle so it can only sence light of objects that is exsactly pinted it to (this wod be only useful in a shoting game there you have to point the "gun" directly in an LED)
I just cant find the photoresistor of mine wich has an 130° angle

just short out the photoresistor while youre experimenting with it.

Someone Electro · 15th April 2005, 05:10 AM

Its working and it makes bzt evry so and so at 0.02 mA curent draw(whith 3.9V) it wod run 6 years on my 1150mAh litium cell! amazing!

and it ran a long time of an a cuple of caps i put on the power rails(2470uF to be exsact)

the mirophone wod betect if the guy starts yeling or an vibraon detrctor to detect the guy walking around the room

In the afternon il start maing it smarter

btw:
I fixed the phototransistor thing ba making it way more sesitive (that votage divider thing.you know)

we beter start sending each other PMs or lets get in a chat room somtine.

Someone Electro · 15th April 2005, 11:17 AM

here's the surce code of the PIC in mikroBasic

Code:

program beeper

dim light as  word
main:
  CMCON = 7
  ADCON1 = $00
  TRISA  = $FF
  TRISB  = $0
  PORTB = $FF
  Sound_Init(PORTB,2)
  
el:

light = ADC_read(2)

  If light < 200 then
   Sound_Play(10,10)
   delay_ms(5000)
  end if
  
goto el
end.

As for the conections there is an piezo speker on RB2 and the phototransistor output voltage to RA2.

The PIC is runing on its internal oscilator so no crystal

This one behaves like the one zatch made and as you see the code is very simple.

Il post the new code that has timing based on how fast do the lights get thurnded on.

btw:
what did you do whith your amp mether? (mine has an fused 200mA max input and an unfused 20A max input so its kinda hard to blow it)

zachtheterrible · 15th April 2005, 11:04 PM

Hey electro. Do you have microsoft instant messenger? Or AOL? I could redownload the AOL.

Not sure what I did with my ammeter. I think I connected across a 9volt battery while it was on a very small reading. Its a cheapo $3 one so i just got another one.

subahu · 23rd June 2005, 09:51 AM

Quote:

Originally Posted by zachtheterrible

If you want revenge that won’t kill someone, just make them go insane, have I got the thing for you!! I whipped this device up over the last couple of days and couldnt be more satisfied :lol:

Place this in a room where somebody sleeps. While the light is on, this circuit will not make a peep. When the light turns off though, the circuit will stay quiet for about 10 seconds (determined by the 1000uf cap and the 22k resistor) and then turn on. When they hear it, they will get up and turn on the light to look for it, but of course it will turn off. Thinking that they are imagining things, they will turn off the light and go back to bed. 10 seconds later, they will hear it . . . it’s a vicious cycle :twisted:

How it works: When the LDR senses light, it turns Q1 on, which in turn makes Q2’s base more negative than positive: transistor (and buzzer) is off. When the LDR senses no light, it turns Q1 off. The capacitor discharges through the 22k resistor, all the while causing Q2’s base more negative than positive (the 10 sec delay). When it is done discharging, the 22k resistor biases the base of Q2 positively, which turns the transistor and the buzzer on. Simple as that :lol:

To make a longer delay, just increase the capacitance. Since the 22k resistor serves a dual purpose: draining the capacitor and biasing Q2, it should not be made a higher value to increase the length of the delay because it then won’t be able to bias Q2 correctly. Of course you can experiment. I think that the value can be increased a bit more. If you want to shorten the delay, by all means, decrease the value of that resistor, just as long as the value is so low that Q2 will receive too much current through the base and damage it. I’m not sure if this will happen with so low a supply voltage, but beter 2 be safe than sorry.

The 5k POT and the 2.2k resistor in series with it work very well with the 3-16 volt buzzer. If it is a small room, lowering the value of the POT will make the buzzer quieter and harder to find. If you use a different buzzer, you will just have to experiment to find the right value of resistor(s). Just make sure that you turn the buzzer WAAAY down to where u can barely hear it, that way, they will have a very hard time finding it.

Any small small signal NPN transistor will work for NPNs in the circuit, i personally used 2n3904's cuz i have a ton of them, but like i said, anything will work.

This circuit is EXTREMELY sensitive to light. Just turning on a flashlight in the room will turn it off.

If requested, I will provide a PCB, although u will have to make sure that the capacitor, the POT, and the buzzer will fit on it.

Have fun . . . and don’t be too cruel :cry:

where Do we give an input to the circuit?

audioguru · 23rd June 2005, 05:03 PM

Light is the input to the circuit. The Light Dependent Resistor's resistance changes a lot with the amount of light shining on it.

geethurs · 12th July 2005, 10:01 AM

seems interesting. :roll:

charle08 · 16th July 2005, 06:20 AM

hmm.. a nasty project! lolz! nice and cool one! but it's kinda better if it trigger when he/she is in the middle of his/her dreams!

about 5-10 minutes.

zachtheterrible · 18th July 2005, 07:05 AM

that could be done charle. only problem is you would need a rather large capacitor.

you could do it with a 555 and you wouldnt need so large a cap.

electronic mind · 18th September 2005, 09:29 AM

how can a buzer which is (3-16) VDC be able to generate a sound when the Vcc is only 1.5 V (forgetting about the resistors)

zachtheterrible · 19th September 2005, 02:05 AM

Quote:

Originally Posted by electronic mind

how can a buzer which is (3-16) VDC be able to generate a sound when the Vcc is only 1.5 V (forgetting about the resistors)

Ummmm, i dunno, it just does :lol: Its not loud or anything.

pike · 19th September 2005, 06:48 AM

it just doesn't go at the specified frequency, i suppose. I'm assuming its a mechanical buzzer that is.

14th April 2005, 02:46 AM	(permalink)
zachtheterrible Experienced Member	Im gonna have to do that someday. Not now, as you may have read ive got a rather large alarm project that im working on. __________________ I'm no electronics god, i just talk too much.

14th April 2005, 04:45 AM	(permalink)
Someone Electro Experienced Member	Il try to make it since i have an PIC16F88,programer,5v regulator... I suck together an perogramer out of a cumple of transistors and resitors and its on the LPT.The down side is i have to have an external power suply of 13v an 5V anyway what do ou know about PICs? Hmm...meaby an phototransistor on ADC and an piezo speker __________________ Il give you shocking experience.

14th April 2005, 06:24 PM	(permalink)
Someone Electro Experienced Member	i got the hardware working but the damn phottotrasistos has 15° angle so it can only sence light of objects that is exsactly pinted it to (this wod be only useful in a shoting game there you have to point the "gun" directly in an LED) I just cant find the photoresistor of mine wich has an 130° angle Now i have to make the program (10 bit output from the ADC is casing me headaces becose 10 bit is harder to work whith than 8 bit ) First il try to make it work like the "analog original" works so your circuit will have an digital brother but then il try to complicate it a bit like the thiming thing. wod be also cool to conect an microphone in but in not going to do that. It also has an super small curent draw.Wean slilent it drawn 0.04 mA an that wod run on my litium cell for about 2 years continuestly by runing it at 34kHz(you beter not run it for that long since the guy may end up by the psycaetrist and if he finds out you cod end up in a hospital) you can see an slight delay on the leds since it has to divide an 10 bit number whith 120 on such an low freqency (but i goes super smoth wen run at 10Mhz but then it draws 1.3mA) how much dose your circuit draw? __________________ Il give you shocking experience.

15th April 2005, 05:10 AM	(permalink)
Someone Electro Experienced Member	Its working and it makes bzt evry so and so at 0.02 mA curent draw(whith 3.9V) it wod run 6 years on my 1150mAh litium cell! amazing! and it ran a long time of an a cuple of caps i put on the power rails(2470uF to be exsact) the mirophone wod betect if the guy starts yeling or an vibraon detrctor to detect the guy walking around the room In the afternon il start maing it smarter btw: I fixed the phototransistor thing ba making it way more sesitive (that votage divider thing.you know) we beter start sending each other PMs or lets get in a chat room somtine. __________________ Il give you shocking experience.

15th April 2005, 11:17 AM	(permalink)
Someone Electro Experienced Member	here's the surce code of the PIC in mikroBasic Code: program beeper dim light as word main: CMCON = 7 ADCON1 = $00 TRISA = $FF TRISB = $0 PORTB = $FF Sound_Init(PORTB,2) el: light = ADC_read(2) If light < 200 then Sound_Play(10,10) delay_ms(5000) end if goto el end. As for the conections there is an piezo speker on RB2 and the phototransistor output voltage to RA2. The PIC is runing on its internal oscilator so no crystal This one behaves like the one zatch made and as you see the code is very simple. Il post the new code that has timing based on how fast do the lights get thurnded on. btw: what did you do whith your amp mether? (mine has an fused 200mA max input and an unfused 20A max input so its kinda hard to blow it) __________________ Il give you shocking experience.

15th April 2005, 11:04 PM	(permalink)
zachtheterrible Experienced Member	Hey electro. Do you have microsoft instant messenger? Or AOL? I could redownload the AOL. Not sure what I did with my ammeter. I think I connected across a 9volt battery while it was on a very small reading. Its a cheapo $3 one so i just got another one. __________________ I'm no electronics god, i just talk too much.

23rd June 2005, 05:03 PM	(permalink)
audioguru Experienced Member	Light is the input to the circuit. The Light Dependent Resistor's resistance changes a lot with the amount of light shining on it. __________________ Uncle $crooge

12th July 2005, 10:01 AM	(permalink)
geethurs New Member	seems interesting. :roll:

16th July 2005, 06:20 AM	(permalink)
charle08 New Member	hmm.. a nasty project! lolz! nice and cool one! but it's kinda better if it trigger when he/she is in the middle of his/her dreams! about 5-10 minutes. __________________ † \| cHron0Cr0Ss \| †

18th July 2005, 07:05 AM	(permalink)
zachtheterrible Experienced Member	that could be done charle. only problem is you would need a rather large capacitor. you could do it with a 555 and you wouldnt need so large a cap. __________________ I'm no electronics god, i just talk too much.

18th September 2005, 09:29 AM	(permalink)
electronic mind New Member	Question? how can a buzer which is (3-16) VDC be able to generate a sound when the Vcc is only 1.5 V (forgetting about the resistors)

19th September 2005, 06:48 AM	(permalink)
pike Experienced Member	it just doesn't go at the specified frequency, i suppose. I'm assuming its a mechanical buzzer that is. __________________ www.winpicprog.co.uk - Great PIC language tutorials.

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