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Search for Alarm in Topics

alarm video

Wath the video if you seen the : knex alarm.

Topic by knex gun and grenade maker  

Distance Alarm?

Hello, I am interested in seeing if I can create some sort of alarm for my 10 year old son.  He has autism and I'm looking for something kind of like a house arrest ankle bracelet BUT i don't want it to track where he is. (Not at this point anyway).   For now i just want to see if I can make a distance alarm.  I would strap a bracelet to his ankle and I could carry the alarm unit in my pocket to If he got more than 100 feet from my device I would hear an alarm.  He has an issue with wondering away and the electronic monitoring companies want to charge hundreds of dollars to put a house arrest type monitor on him.  If i could make  something that would warn me when he starts to wonder that would be amazing! Can anyone point me in the correct direction? Thanks

Topic by author-unnknown    |  last reply

Car Alarm

I just had an idea.... Someone needs to make a car alarm app for smart phones. It can use the microphone to listen for breaking glass, the speakerphone for playing pre-recorded messages (step away from the vehicle, the police have been called), the camera can sense movement inside the vehicle and the GPS can sense (and report) movement of the vehicle. All of this information can be sent in real time to the other phone that you carry with you. Installation is as easy as turning it on and tossing it in the seat! Compatible with any car! Battery backup! :)

Topic by AsianSpanker    |  last reply

Fire alarm!

This afternoon a couple of guys from the Mexican restaurant next door came up our stairs and asked how to get to the roof. They said something about a fire and smoke and it being urgent. We pointed them to our fire escape which has a ladder to the roof and then, for some reason, they lost interest and left. We were wondering if, you know, this was actually important or something when the fire engines started racing towards our building. So we looked out and two fire engines with ladders showed up along with 6 other vehicles and a total of about 25 firemen. It was on! The two ladders extended up to the top of the building where some smoke was coming out and a fireman climbed up to take a look. Fortunately, it didn't look too bad as none of the other firemen went up. Within about 15 minutes they started packing up and left. Just another day in downtown San Francisco.

Topic by fungus amungus    |  last reply

Alarm Clock?

Is there a relatively easy way to make an alarm clock?

Topic by kylechu  

Digital Alarm

This is Raj from India, I want a help from you. reg i want to build a system which works according to time. it is just like a alarm . i want the alarm clock that can play a different song at different set alarm time from the memory card. and i want the alarm time as a digital input to perform various tasks as to drive digital ON/OFF switch. and all this i want to be in a very very little place. please help me out in this.

Topic by rajuwithualways    |  last reply

Locker alarm Answered

I want to know how to make a song play every time i open my locker using my mp3 player and please keep it under $30

Question by deidei2299    |  last reply

Loudness measurement alarm? Answered

Hi guys, I'm looking for a plan to make a very simple plan for a device that can detect the loudness of a sound and sound an alarm if it is beyond a programmable dB value. Best regards, Vuur.

Question by Vuur    |  last reply

Computer Activated Alarm

Hi, I am trying to make a simple alarm system for ill patients, the alarm will be activated through a mouse click on an alarm icon and trigger an alarm connected to the PC. Does anyone have any ideas on how to tackle this problem? Many thanks in advance :)

Topic by RohanQ    |  last reply

Plasma alarm clock?

I am thinking it might be fun to hack the speaker output on a digital alarm clock to somekind of plasma device that uses a flyback transformer. Something along the lines of a lightning alarm clock that was released a few years back.

Topic by argos090    |  last reply

Laser Alarm System

Hello guys, I need some help building a circuit. I'm new to electronics, so go easy with me. Is there a way to build and laser alarm circuit but instead of the alarm going on just when the beam is broken the alarm stays on until I turn it off? Circuits like Kipkay's only go off when the beam is broken. How can I make the alarm stay on once the beam is broken? Thanks

Topic by HavocRC    |  last reply

Alien door alarm???

Ok, I wanted to make a door alarm, but the resulting "alarm" would be the sound of the alarm on the Nostromos, from the Alien movie. How could I pull this off??? Thanks a ton!! -Sylar

Question by Sylar521  

Laser alarm circuit

I am searching for a circuit which can drive a siren circuit like this and can be activated by a laser pointer.I have tried a lot of these circuits but all had the same problem:The siren sounds only for a few seconds(As long as the interruption of the laser beam...) Thank you in advance!

Topic by pizza1993    |  last reply

Shock alarm clock

Hi,  I want to build a Alarm that will shock you when the clock hits a certain time i am new to this could someone help me out ?!

Topic by josephwilmott2    |  last reply

Alarm clock mod

I took apart my alarm clock and took out the speaker and put in a headphone jack. Now it can wake me up and i was wondering if someone could help me figure out what the specific alarm electric thing looks like. I want it to be able to set off a motor that pulls off my sheets. I know absolutely nothing about circuit boards and things like that. any info would help. thanks

Topic by pizzadeliverykid    |  last reply

Latching Laser Alarm?

I'm here again guys to ask you this question, will this circuit work? More Importantly, is the LDR placed correctly? 'cauz I'm having doubts on this circuit :S  And I'm going to make a PCB for it, and I'm too lazy to test it on a bread board (too lazy to solder wires on parts with big pins, e.g. DC Jack). If this circuit will not work I'm going to switch to relay laser alarm types. Just give me the answer please. Thanks :D 

Question by Charles Mendoza    |  last reply

Hacking An Alarm Clock

My sister (yes, the one for whom I made earrings) wants me to modify an alarm clock to run a small electronic device when it goes off. Preliminary research has given me two methods:1) A digital clock with a 555 timer circuitIn this setup, a 555 timer circuit is used to translate the signal to an alarm speaker/piezo disk into a relay. When the clock goes off, the relay clicks, and any electrical device that is run through the relay has power.2) An analog clock with a transistor amplifierIn this version, the analog clock seems to just have a straight DC output to the alarm. The transistor is used to amplify the DC to drive the motor of a fire bell.Which of these would be easier to implement? The device I am supposed to use runs off of 3VDC, so I was just going to run the power line through the relay or through the transformer.

Topic by CameronSS    |  last reply

the laser trip alarm

Https:// I find this project absolutley great but I want to know if there is a way to make it so when the alarm is triggered i can be notified without having to look at the LED on the circuit board. so for example i have the laster and circuit board at the enterance to my house, and im in the basement 1 floor under, is there a way to make it so a light or buzzer is triggered where i am as opposed to upstairs?

Topic by astrozombies138    |  last reply

Customized Alarm Clock

What I want to do is this, -get rid of my alarms stupid sounds -insert a custom sound -do it cheap -and make it small enough I can still put it in a custom casing (the casing is the easy part, I'll have no issue making that.) I have looked around and have seen several ways to hack alarm clocks but I can't see how any of them would help me out with this particular problem. The way I see it I will probably need to rewire the clock so that it sends power to an external device when the speakers are supposed to go off. The only other way I can think of is having a small computer with one of those pre-programmed clocks but that would be more expensive than buying the sound recording clocks and a bigger pain to fit into the casing. I also think I heard someone talk about making homemade circuits, I don't know if that would work at all but it's worth mentioning. I would like to be able to find easy to follow instructions that are CLEAR and not super complicated. Any help would be appreciated! BTW, yes, I have looked at the sound recording clocks online and they all look like crap or are way to expensive to bother with. 

Topic by cward5  

Alarm using RTC.

Hi, I am new to arduino and RTC DS1307. I am trying to create an alarm using RTC and arduino. I have a buzzer that I have connected to arduinio and also I have connected RTC module to it. I am programming the arduino in such a way that whn the timer runs off, it produces a sound from the buzzer. I am trying to use Time.h and TimeAlarms.h libraries. I dnt know how can I make the timer buzz the buzzer.  This is the code I ve done so far.  #include #include "RTClib.h" #include #include ; RTC_DS1307 RTC; void setup () {     Serial.begin(57600);     pinMode(4, OUTPUT); // set a pin for buzzer output     Wire.begin();     RTC.begin();   if (! RTC.isrunning()) {     Serial.println("RTC is NOT running!");     // following line sets the RTC to the date & time this sketch was compiled     RTC.adjust(DateTime(__DATE__, __TIME__));   } } void loop () {       DateTime now =;     Serial.print(now.year(), DEC);     Serial.print('/');     Serial.print(now.month(), DEC);     Serial.print('/');     Serial.print(, DEC);     Serial.print(' ');     Serial.print(now.hour(), DEC);     Serial.print(':');     Serial.print(now.minute(), DEC);     Serial.print(':');     Serial.print(now.second(), DEC);     Serial.println();     Serial.println();        delay(1000);             //Somthing sould come here to make the buzzer buzz     soundBuzzer(); //sounds the buzzer        buzz(4, 2500, 500); // buzz the buzzer on pin 4 at 2500Hz for 1000 milliseconds } // This is the function to make the buzzing void soundBuzzer(){   } //This is for the buzzer. It produces a beep. void buzz(int targetPin, long frequency, long length) {   long delayValue = 1000000/frequency/2; // calculate the delay value between transitions   //// 1 second's worth of microseconds, divided by the frequency, then split in half since   //// there are two phases to each cycle   long numCycles = frequency * length/ 1000; // calculate the number of cycles for proper timing   //// multiply frequency, which is really cycles per second, by the number of seconds to   //// get the total number of cycles to produce for (long i=0; i < numCycles; i++){ // for the calculated length of time...     digitalWrite(targetPin,HIGH); // write the buzzer pin high to push out the diaphram     delayMicroseconds(delayValue); // wait for the calculated delay value     digitalWrite(targetPin,LOW); // write the buzzer pin low to pull back the diaphram     delayMicroseconds(delayValue); // wait againf or the calculated delay value   } } I am really bad at programming so sorry for mistakes. But please I need help.

Topic by Bam Boy    |  last reply

Out of range alarm

I'm working on a project where I need to have a transmitter and a receiver with an alarm, so when they are apart a certain distance the alarm goes off. I need the alarm to be attached with the transmitter not the receiver, where it will be attached to a valuable stuff for example.

Topic by AmmarK22    |  last reply

panic alarm data?

 i request to get data about panic alarm.

Question by nelson ndegwa    |  last reply


Hello I want to create a anti theft alarm system for heavy Batteries mostly used in communications systemIt is called VRLA Cell. It consist of 24 cells each of 2.1 volt .So when a cell is lifted or its get disconnected from the circuit a Alarm should be raised at the premises itself and should also extend alarm o nearest control room.So please suggest the way to create such system .Thankyou

Question by PiyushS93  

Simple alarm system

How can I build a simple alarm system for a garage using a 30 watt 12 volt siren, a keyed outside activation switch and an inside motion detector. 110 volt power in garage.thank yougarry

Question by garhug    |  last reply

Reverse proximity alarm ?

If my backpack or suitcase was moved away from me an alarm would go off in the luggage if the luggage was moved more than a few meters . This would be a 2 piece gadget , 1 piece in the luggage and 1 in my pocket . Cheers

Question by Witold888    |  last reply

alarm clock help?

Hey, i want to make an alarm clock that i can either wear or have it wireless. other info: headphones would be ok if the device is small enough i can stick it in a headband or somethong i dont really have any money to spend on on parts so re-purposed stuff is great no aduino please! (i dont have one) any advise would be great! thanx

Question by cheesewzrd    |  last reply

Wireless water alarm

Hi all. Hoping I can get some suggestions. I have a water alarm in my basement, when it's sensor gets wet, it beeps. This does me no good since I can't hear it. What I'd like to do, it hack it so that instead of beeping, it lights a led I can hide somewhere in the house. Maybe in one of the wifes stupid knick knacks in the living room. If I just needed to wire the led to the beeper, I could figure that out. But I want it wireless. Any suggestions? Mechanically, I'm good. I know how to assemble, disassemble, solder, etc, but I don't know much about the electronics involved. I'm thinking I can use an inexpensive wireless doorbell as my transmitter and receiver. So, I guess what I need to do, is figure out how to incorporate the doorbell button into the alarm so when the alarm triggers, it activates the doorbell. Then, install an led in place of the chime and hide the whole shebang in something. (If it could also send me a text, that would rule, but it's way outside of my current skill level.) Will it work? How do I do it?

Topic by nitsuj1098    |  last reply

Alarm Buzzer Driver? Answered

So I have removed a buzzer from an out of date smoke for fun use, but it doesn't work as expected.  I set up a driver circuit with a 555 and some resistors/capacitors.  I don't deal much with IC's or the 555 and haven't really bothered to learn to use them properly, but I took an LED flash circuit and vastly decreased the capacitance, upping the frequency drastically.  I have included an image of the circuit.  The 555 runs on 6 volts, the buzzer runs on 9 (the blue wires).  The volume was ok, but nowhere near expected levels and I wondered if it had to do with the higher than normal frequency.  I attached it to an arduino and ran the tone function from below audible to above it (whole frequency range) and the sound was very quiet, even using an npn transistor and 9 volts right off the battery hitting the buzzer.  As you can see, the buzzer has 3 leads, i only used two, but as with most 3 poll buzzers I assumed one was just for some form of feedback.  Any voltage in any direction across the three produces sound, so should I use all three, and if so how should I do so.  How would you recommend driving this buzzer?

Question by    |  last reply

How To Use the Alarm from an Alarm Clock in Something Else?

I wanted to make an alarm type thingy, ad I want to use the alarm from an alarm clock. I don't know how though, I tried connecting a cell to the wires that were already on the alarm, but it won't work. I think it's one of those piezo-electric crystal thingies. And I know I have to have pressure on it to work. How exactly would I use it?

Topic by Aeshir    |  last reply

how to make a Fridge alarm?

Hi All, I want to make a fridge alarm, but i dont know the right configuration or maybe I need to buy a different time delay module?  Please help me Kind regards, Jonathan

Topic by JonathanH243    |  last reply

Wireless activated buzzer/alarm

Can someone help me with this? I need a wireless activated buzzer or alarm. Similar to the cheap wireless doorbells where you push the button on the remote and the bell rings. Release the button, and it stops. But it needs to be a loud sounding buzzer or alarm, fairly high decibels, and did I mention very inexpensive? Also, the buzzer/alarm part needs to be as small as possible. I appreciate all your help!

Topic by wolfsmane    |  last reply

Infrared Beam Burglar Alarm

Could someone please tell or show me a fairly inexpensive way to throw an infrared beam across my office and once it's tripped by an intruder an outside alarm or siren (I mean the loud ones-like you can hear several blocks away)would go off. I'm so impressed by the quality of minds on this website. I know someone can probably help. Bless You All.Thank You So Far!

Topic by ropor    |  last reply

Light Alarm Clock Help

I want to build my own version of the the Progressive Light Alarm Clock by Phillips found here. Theres several of these products on the market, but most are $100-200. Does anyone have any ideas of how to make one yourself?

Topic by Navygreen33    |  last reply

trigger retail door alarm

I know most people that think of retail exit door alarms want to avoid setting them off, but is there a way to purposely trigger them, especially from a distance? i am reasonably good with a soldering iron, ok using a ohm-meter and beginning on using oscilloscope. and i have lots of junk PC/PC parts and various other electronics around to strip for parts... (if that helps any). thank you for reading --rex

Topic by rexifelis    |  last reply

DC power drop alarm Answered

I need a very simple way to see if power is ever lost to load.  I am trying to run a long term test of at least 60 days.  I have a UPS that is powering a load and I need to be able to determine if the 12 - 15 V dc that the UPS is providing is ever lost. The UPS has a battery that will supply power if the AC input is lost.  The solution can be very simple and I really don't want the load to be reconnected if the current going to the load is ever lost. I need to know if the load is ever not powered, even for a brief instant.  I was hoping there might be some type of switch that would open if the current stopped flowing through it.  Sorry for the simplicity but I know very little about electronics.  Thanks for any help or advice.

Question by brentatespicorpdotcom    |  last reply

Shock Alarm wrist Watch?

Their basically is not a thing like that out their. I want to build a wristwatch that can shock me at a resettable time. I will keep it on when I sleep so It has skin contact. How do I do this? Please help me because I wont wakeup from anything else tryed everything and I hope this will work.

Question    |  last reply

Help! Alarm Clock Renovation

Alright, this is a crazy class project I've taken on, so bear with me. What I want Alarm clock display that can be custom programmed to a non-time sequence.  (IE: 666, 777, 888, etc.) Programming above sequence to blink repeatedly. Converting alarm clock from power cord to battery. (Not necessary, but one of the models has an old AM/FM radio display. Making this display move "randomly" would be amazing.) What I have Alarm clock #1:  Model No: KMC 500; "Electronic LED Alarm Clock"; Power supply AC 120V 60HZ 5W Alarm clock #2: Trade Name "Realistic"; Chronomatic-233; Model No: 12-1540; Frequency Range: AM 520-1620KHz  FM 88-108MHz; Power Supply AC 120V 60Hz 10W Cold soldering kit Limited budget If it would help, I could take pictures of the clocks mentioned above. They're from the 70's, with the "simulated walnut grain finish" and red display screens.

Topic by Kizoku  

Sunrise lamp adaptor alarm

Hi guys and compliments for the comprehensive forum! I would love to have one of those sunrise simulator alarm clock out in the market but since I have no bedside table, and the wall cover with wood on one side, I am looking for a way to make an adaptor to start dimming my existing lamp at a precise time, like 7 am. I found out this product:  but the producer told me it does not work outside US (I'm from Italy) since we have 220V main and the gig would fry out. Also he told me it cannot be modified and power adapters don't work. Any idea on how to build one? Thanks a lot! Sam

Topic by samumar82    |  last reply

Vibrating alarm clock help

 Hey guys,  I'm a soon-to-be college freshman and a very heavy sleeper. I contacted my soon-to-be roommate, and it turns out he's a very light sleeper and is frightened by waking up to loud noises. Of course, coming from a house where I used a phone hooked to a guitar amplifier as an alarm clock, I figured I'd have to change my waking habits. I heard from my father about an alarm clock system that utilizes pillow-mounted vibrators, but that costs waaaay too much, and I'm already going to have to balance a job or two just to get by paying tuition. Besides, I don't like buying things I can build at home. So here's my situation: I have a five-volt vibrating massager that plugs into USB ports that I wanna use as a pillow-mounted vibrator in college, so I don't wake my roomie up with a fright. My phone has a 3.5mm plug that I use to connect it to the guitar amplifier. My question is: How can I build an amplifying circuit that'll power the vibrating motor enough to work with the signal from the phone (or any alarm clock signal, for that matter)? I need 5 volts to power the motor. That much I know. I haven't measured the signal from the phone, since I haven't access to a volt-meter, at the time. HELP ME PLEASE!! Thanks.

Topic by Usf    |  last reply

Ultimate Bathroom Alarm Clock...

I have a Burning question on building the ultimate bathroom alarm clock.  I like to have a nice LED clock.  But also be able to alarm out saying BRUSH your TEETH. But also. for the OLDER folks.  to take your medications...  and maybe even take that second one ONE step further.  how about to be able to Dispense your medication for you...   So multiple alarms for multiple people...     and design it however you think would look and feel the best.  But this is MY ultimate WANT and Desire!!!!

Topic by lonelydragon757    |  last reply

Arduino alarm on mechanical clock

I am new to arduino and I am trying to hook a mechanical wooden gear clock to trigger an alarm or chime when the clock hands hit 12. Does anyone know how I can go about this or any tutorial/instructable that does this or something similar?

Topic by zippystix    |  last reply

Hacking a projector alarm clock?

I have small projection alarm clock that projects time and temparature on the wall powered by a small LED. The light emited by that LED is small and hence the image is also lightly visible. I wanted to hack this one and put a high powered LED to get a brighter image on the wall . What can be done?.?

Question by chicagopooldude    |  last reply

Arduino alarm clock help!

Hello I am trying to make a pressure switch for my alarm clock where when I stand on it for a certain amount of time the alarm will stop. I've never done any arduino work before so I was wondering what board would best suite me for this project. I found this one but I don't know if it will work. I also found some code online that I think would work. Here is the link for the code: Also would this be how I would set the entire thing up?Do I need any resistors? What type of power supply would I be able to use?

Topic by boom man56    |  last reply

Virus in Instructable or false alarm?

When I try to open the following link, my Avast anti-virus sounds the alarm and aborts the connection. My question is: Does Avast have a screw loose or is this something that is a danger to the community and should be removed?Please be warned--possible virus attached!!!The link is: and Virusses by ELECTROfun)Thanks for any responses

Topic by jd570a    |  last reply

Make alarm clock louder

I am an incredibly heavy sleeper, and looking for a way to make my alarm clock loud enough to wake the dead.t is not a clock radio; it plays a recorded message. It is 110v AC. It does not have a line out - I tried to add one and plug in amplified speakers, but no luck. I'm capable of soldering but have no idea how to make this happen. I'm stuck on using this alarm because I can record people yelling at me.Thanks! PS I have tried four alarms at once tuned to odious stations, light timers, things that beep, etc.

Question by brandegor    |  last reply

Alarm airsoft gun...thing

I want to make an alarm out of an air soft gun and a web cam. I know how to make it so the web cam will go off if something passes it, but I can't thing of a way to make a servo pull the trigger on the gun, without having me around to press a button on an FM receiver i would just like it to happen all by it's self. The gun is electric by the way.

Topic by CowGuy    |  last reply

Arduino intruder alarm modification

We have a professionally installed burglar alarm system that dials out (over a dedicated landline) to a monitoring station when an intrusion is detected.  I'd like to modify it to send us an SMS (via the mobile phone network) and/or email (via wi-fi on a different landline) as well, just in case the phone line is cut, and to make sure we get notified immediately - the monitoring station tries to call on the landline first, then it calls our keyholders and the police, which all takes time.  If I'm 5 minutes away and the alarm is triggered, I'd like to know straight away so I can rush home. The alarm company have quoted a huge sum to make this change, because an updated control control panel would be needed to deal with the texting/emailing.  I can't go cutting into their system or it will invalidate the maintenance contract, so I need to pick up when the alarm is triggered without any physical connection.  Short of remotely detecting a current in the cable to the siren (a 12V DC signal, so how would I detect that?) it occurs to me that using Arduino to listen for the siren might be the best bet.  But I'm an Arduino beginner and I have no idea whether it would be better/easier to detect a noise over a certain threshold - the siren is very loud, but the noise from the adjacent road can be pretty loud too - or to try and detect the particular sound frequency of the siren.  All suggestions gratefully received. 

Topic by Yorkshire Lass    |  last reply

Credit Card Reader Alarm

Does anyone know of a way to wire a MAGTEK 21080148 credit card reader in anyway to generate an on or off signal when using a credit card with a certain code on it? It uses a ps/2 plug. Does anyone see a way which it is possible to set up? Please post any ideas you have for it.

Topic by InventingMan  

IR laser detector alarm

With the new Infrared laser pointers etc. there is no way to tell if light is on or not. I think there is a need for a IR laser light detector that is small enough to fit in your pocket and could be clipped to your shirt. If a IR laser was pointed in your direction the sensor would chirp or make a noise. I've noticed several places selling IR laser pointers. I think they are dangerous and very little use for them, since they are invisible. Anybody want to make one? If you do I want one.

Topic by paduckaartist    |  last reply