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This Auto Anti-Hijack Alarm Circuit Diagram was designed primarily for the situation where a hijacker forces the driver from the vehicle. If a door is opened while the ignition is switched on - the circuit will trip. After a few minutes delay - when the thief is at a safe distance - the Siren will sound.

Where it differs from the first two alarms - is in what happens next. I'm obliged to Victor Montanez from the USA who suggested that the engine cut-out should not operate - until the vehicle comes to a stop. That way - the engine will not fail suddenly or unexpectedly. And the hijacker will retain control.

I haven't been able to implement Victor's excellent suggestion completely - because I couldn't think of a simple, reliable and universally applicable way of sensing when the vehicle has come to a stop.

Instead - I have postponed engine failure until the ignition is switched off. Once the thief turns off the ignition - the engine will not re-start. Clearly - there is no certainty as to when this will occur. But I think it will occur sooner rather than later. Because there's a strong possibility that the hijacker will turn off the ignition - in an attempt to silence the siren. 

As well as acting as a Hijack Alarm - this circuit offers some added protection. Like the Enhanced Hijack Alarm - it incorporates Jeff Chia's suggestion. That is - every time the ignition is switched on - the alarm will trip. So it will protect the vehicle whenever you leave it unattended with the ignition switched off - even overnight in your driveway.

Before fitting this or any other engine cut-out to your vehicle - carefully consider both the safety implications of its possible failure - and the legal consequences of installing a device that could cause an accident. If you decide to proceed - you will need to use the highest standards of materials and workmanship.

Notes

You're going to trip this alarm unintentionally. When you do - the LED will light and the Buzzer will give a short beep. The length of the beep is determined by C4. Its purpose is to alert you to the need to push the reset button. When you push the button - the LED will switch-off. Its purpose is to reassure you that the alarm has in fact reset. 

If the reset button is not pressed then - about 3 minutes later - both the Siren and the Buzzer will sound continuously. The length of the delay is set by R8 & C5. For extra effect - fit a second siren inside the vehicle. With enough noise going on - you may feel that it's unnecessary to fit the engine cut-out. In which case - you can leave out C7, D8, R12, R13, Ty1 & Ry2.

When the ignition is switched on - C3 & R4 are responsible for tripping the alarm. By taking pin 1 low momentarily - they simulate the opening of a door. If you don't want the alarm to trip every time you turn on the ignition - simply leave out C3 & R4. 

Because the voltage on C3 may be reversed - the capacitor needs to be non-polarized. But connecting two regular 22uF capacitors back to back as shown - will work just as well. Because non-polarized capacitors are not widely available - the prototype was built using two polarized capacitors.

To reset the circuit you must - EITHER turn off the ignition - OR close all of the doors - before you press the reset button. While BOTH the ignition is on - AND a door remains open - the circuit will NOT reset.

The reset button carries virtually no current - so any small normally-open switch will do. Eric Vandel from Canada suggests using a reed-switch hidden behind (say) the dash - and operated by a magnet. I think this is an excellent idea. As Eric said in his email: - "... that should keep any thief guessing for a while."

 

How you prevent the engine from starting is up to you. It should happen when Ry2 de-energizes. The contacts of Ry2 are too small to do the job themselves. So use them to switch the coil of a larger relay. Remember that the relay must be suitable for the current it's required to carry. Choose one specifically designed for automobiles - it will be protected against the elements - and will give the best long-term reliability. You don't want it to let you down on a cold wet night - or worse still - in fast moving traffic!!! Remember also that you must fit a 1N4001 diode across YOUR relay's coil - to prevent damage to the Cmos IC

YOUR relay should drop-out when Ry2 de-energizes. Wire YOUR relay so that when it drops-out the engine will not start. Because turning-off the ignition will cause both Ry2 and YOUR relay to de-energize - the standby current will be low - and the engine will be disabled while the vehicle is parked.

The circuit board must be protected from the elements. Dampness or condensation will cause malfunction. Fit a 1-amp in-line fuse AS CLOSE AS POSSIBLE to your power source. This is VERY IMPORTANT. The fuse is there to protect the wiring - not the components on the circuit board. Please note that I am UNABLE to help any further with either the choice of a suitable relay - or with advice on installation.

Both the Siren and the Buzzer will go on sounding until the alarm is reset. The circuit is designed to use an electronic Siren drawing up to about 500mA. It's not usually a good idea to use the vehicle's own Horn because it can be easily located and disconnected. However, if you choose to use the Horn, remember that Ry1 is too small to carry the necessary current. Connect the coil of a suitably rated relay to the "Siren" output. This can then be used to sound the Horn.

This is a simple PIC Security System Dials Your Cell Phone Circuit Diagram. Do-it-yourself phone dialer security system calls your cell phone, office etc. whenever a door or window is opened, or panic button is pressed. Great Home Alarm.

PIC Security System Dials Your Cell Phone Circuit Diagram



The circuit consists of a small PIC microcontroller, assembly program, and a few other parts to detect a switch closure from an open door, window, or manual push button and then dial the cell phone number, and transmit a steady tone to indicate the source of the call. The circuit uses the pulse dialing system to interrupt the line connection a number of times to indicate each digit. Pulse dialing (the oldest form of dialing) works by actually disconnecting or "hanging up" the phone line a number of times to indicate each digit. For example, the digit "5" would be dialed by disconnecting and reconnecting the line 5 times in short intervals of about 100mS. There is about a 1 second pause (with the line connected) between each digit. The timing is not critical and I was able to dial 411 and connect to the local information service just using a momentary push button switch in series with the phone line.

Circuit Operation:
In operation, the switch closure is detected on pin 7 of the processor which activates the reed relay and takes the line off-hook for 3 seconds to establish the dial tone. The processor then dials the number by opening and closing the relay a number of times for each digit. When dialing is complete, the processor waits 3 seconds and then transmits a steady tone of about 300Hz for 30 seconds through the modem transformer. The call is then terminated and the processor waits for the switch to open before resetting.

Design Considerations:

The PIC16F628 (18 pin) processor was selected because I had a few on hand and my homemade hardware programmer only accepts 18 pin devices. A smaller 8 pin device could have been used since only three I/O lines are needed, but the difference in cost is only about $1.50. One of the I/O lines (RA5) is used for programming and is always an input, but can used as a functional input so the switch closure could be detected on this line thus eliminating the need for one pullup resistor. But I elected to use 3 consecutive I/O pins (7,8,9) of the 8 bit port B and leave RA5 pulled up with a extra 10K resistor.

The output pins (8,9) that drive the relay and transformer are limited to 25mA of current each, so an extra transistor (2N2222A) was needed to supply additional current to the relay coil. The transformer resistance is around 100 ohms, so an additional 330 ohm resistor was added in series with pin 9 to limit the transformer current to around 10mA. An LED indicator and 330 ohm resistor were used on pin 8 to observe the dialing activity and indicate the line status. Several of the parts (relay, transformer and blocking capacitor) were obtained from an old 56K modem card.

The schematic shows a 47uF / 50 volt non-polarized capacitor used to block DC current to the transformer, however a regular polarized 50uF cap could be used if correct phone line polarity is observed. The modem was probably designed to work with unknown polarities at different locations, so a non-polarized cap was used. It's possible the cap and 470 ohm resistor can be replaced with a single resistor in series with the line to set the "off hook" line current to around 20mA. This may cause partial saturation of the transformer and reduced audio level, but might work well enough.

The power supply voltage is not critical and a 4.5 volt supply from three AA batteries should work. Or a switching type regulated 5 volt wall transformer can be used. The problem is insuring the relay gets enough voltage to operate. The rest of the circuit should run on reduced voltage. I used a 4.2 volt cell phone charger that worked well.

 Softwre

With just a few days until Apple's big event, we're at the height of rumor season. Will there be a budget version of the iPhone announced? Most likely. Could the next-generation iPhone come with a fingerprint scanner? Eh, maybe. 

We won't know what Tuesday will bring for sure, but in the meantime, here's a look at the biggest rumors making the rounds online:

Rumor: The next-generation iPhone will be called the 5S.

Plausibility: If anything is a shoe-in, it's that the next-generation iPhone will debut. We've seen many pictures and videos of the model hit the web, and assuming those are authentic, we already know a good chunk of what to expect. The name itself, though, is still up in the air (it could be called the iPhone 6). Then again, packaging for Apple's rumored budget iPhone 5C has been spotted, so we're expecting it to stay in the 5 family for now. 

Source: Everyone. Basically.

Rumor: The iPhone's 4.8-inch display will grow to 6 inches.

Plausibility: This would make the device noticeably larger, but it's unlikely a 6-inch display would be unveiled at the event. Leaked photos show that the rumored iPhone 5S' exterior looks the same as its predecessor. They also show that the speakers, Lightning port and headphone jack are all in the same place.

Source: ZDNet

Rumor: The new iPhone's processor will be more powerful than its predecessor. 

Plausibility: Major changes to the iPhone will likely happen under its hood. Apple is rumored to be ramping up the device's A6X processor, while slimming down its form factor. There are reports that the new iPhone will have an A7 chip that runs 31% faster than the chip in the iPhone 5. This seems likely, especially since the device's launchboard has been seen moved slightly to the right, which would leave room for an enhanced battery. What's more, the cutout shape for the dual LED flash looks different in leaked models, which hints at big improvements coming to the camera.

Source: Fox News reporter Clayton Morris

Rumor: The new iPhone will be available in a gold-champagne color. "Graphite" will be another color option.

Plausibility: Very likely. This would be the first true color in the iPhone lineup since previous models were only offered in black and white. 

Sources: weekly.ascii.jp, 

Rumor: The iPhone 5S will include a fingerprint scanner.

Plausibility: This is one of the wackier rumors floating around. Leaked photos show internal components with a cushion near the home button for what could be a scanner. It's noteworthy, however, that Apple patented fingerprint-detection technology last year, and words related to the technology has surfaced in beta code for iOS 7. So perhaps this isn't as out-there as you'd think.

Sources: Nowhereelse.fr

Rumor: Apple will launch a low-cost iPhone 5C smartphone alongside the 5S.

Plausibility: Tons of pictures have already leaked for the iPhone 5C. If the smartphone's rumored budget version debuts on Tuesday with the 5S, it would be the first time Apple has unveiled two separate iPhone devices at once. The low-cost iPhone could help reposition Apple in the smartphone market, as Samsung continues to lead the way with Google's Android mobile operating system. 

Many believe the "C" in iPhone 5C is a nod to China, especially since Apple is holding another event in the world's most populous country on Tuesday, just hours after the one at its Cupertino, Calif. headquarters. Naturally, the cheaper device would be targeted at China's mobile market. The iPhone 5C will reportedly have a plastic backing, which would make it a lot cheaper to manufacture.

Source: iApps.im

Rumor: Apple will be shipping its lower-cost iPhone to China Mobile, the world's largest carrier, with more than 700 million subscribers. 

Plausibility: Apple has reportedly been in talks with China Mobile for years, with previous reports suggesting that a deal was delayed due to compatibility issues and China Mobile's demands for a better deal than Apple offers other carrier partners. Apple CEO Tim Cook has said China will become Apple's largest market, so the move would make strategic sense.

Source: Wall Street Journal

Rumor: The iPhone 5C will come in many different colors.

Plausibility: Press invitations that Apple sent out earlier this week include the tagline, "This should brighten your day," along with colorful dots splashed behind the company's logo. The invites allude to rumors that the iPhone 5C will come in various colors (we've seen leaked images that show the casing in blue, green, yellow, pink and white).

Source: MacRumors

Rumor: Apple TV will get a refresh on Tuesday. A new product related to Apple TV may also launch.

Plausibility: This is a tossup. According to a blog post from trade intelligence platform Panjiva, bills that surfaced indicate a "set top box with communication function" shipped from Apple's Chinese supplier. The bills were for three separate shipments, dated Aug. 11, Aug. 18 and Aug. 25. An Apple TV update will likely be on the horizon, but it's unclear whether it will take place next week.

Sources: PanjivaGigaom

Rumors: The new smartphones will come with Apple's latest iOS 7 mobile operating system software.

Plausibility: iOS 7, which is currently in beta, will almost certainly ship on the company's new products.

Source: Everyone.

Rumor: The iPad and iPad mini won't be getting a refresh at the event.

Plausibility: If you've been waiting for a next-generation iPad or iPad mini, don't place your bets on next week. The tablets are expected to get their own event, possibly in October.

Sources: IBITimes, KGI Securities analyst Ming-Chi Kuo

What other Apple rumors are you seeing pop up online? Which do you hope are true? Tell us in the comments, below.

Fast Fast Now Charge Your iPhone Faster don't worry. complaining about your smartphone's short battery life or the amount of time it takes to charge up are classic examples of the first world problems that can result in impatience and mild irritability.

While we've previously looked at ways in which you can improve your iPhone's battery life, we're now taking a look at how you can make the darn thing charge a bit faster.

There's no secret sauce, unfortunately, but there are a few tips and tricks you can employ to get your cell's battery from flat to full in less time. Have a read of our suggestions below.

Turn It Off

If you want your iPhone to charge faster, anecdotal evidence suggests turning it off — so it's not using any power while it's juicing up — will cut down charge times.

If you don't want to hit the power button, then putting your handset in "Airplane Mode" (from the "Settings" menu) will stop your phone looking for cellular and Wi-Fi signals and can speed up the process.

At the very least, try not to use your phone while it's on charge. Lock the screen by hitting the sleep/wake button on the top right of your handset to give it a break while it recharges.

Use a Wall Charger

Your iPhone will charge fastest from a power outlet, rather than via a USB port. Apple's official advice "for the quickest charge" is to "connect the device to a power outlet using the USB cable that came with the device and an Apple USB power adapter."

Did you know that a battery's ability to hold a charge is significantly degraded by extreme temperatures?

Apple states that "heat will degrade your battery's performance the most" and advises that you "keep your iPhone out of the sun or a hot car (including the glove box)."

Certain cases and covers that trap heat can also be problematic. If your iPhone gets hot while you charge it in a case, then you should notice a difference if you remove it prior to charging.

The official advice is to keep your iPhone as near room temperature (22 degrees Centigrade or 72 degrees Farenheit) as possible.

If USB charging is your only option, there are ways to speed this process up.

 

If you're looking for a fast charge, don't sync your iPhone at the same time. It's also advisable to remove all other USB devices that might be drawing power.

Don't let your computer go into standby or hibernation mode while you're trying to juice up your phone. This might actually drain your handset's power, and could stop the charging process, in some cases

Battery Maintenance

Finally, Apple offers some advice about how to properly maintain your iPhone's battery.

"For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Be sure to go through at least one charge cycle per month (charging the battery to 100% and then completely running it down)."

It's the end of summer and many students are coming out of a brief dip into the professional world  working alongside adults and performing entry level tasks, only to return back to classes in the fall. Some are paid, some are not  some provide both learning opportunities and a chance to build one's network, others less so. Across the board, most students will say that an internship is a better investment of time than sitting at home, or working a regular summer job. 

But some students have found summer experiences that are, arguably, better for their careers — especially those students interested in entrepreneurship, not joining corporate life.

I asked seven students who participated in Lightspeed Venture Partners' summer fellowship — a program that behaves like a startup accelerator without taking equity from the teams — how the experience compared to a summer internship, and what knowledge they'll be taking back to school.

Would you consider a non-traditional summer program? Tell us in the comments.

I read Y Combinator's Hacker News quite a bit. One day when I was browsing, I came across this. We decided to apply and the rest is history. - William Zhou, Planboard

Several of our friends have gone through the Lightspeed program and we heard only good things. - Feross Aboukhadijeh, peerCDN

Through the Stanford Bitcoin Group, a small collection of 8 students with a common interest in Bitcoin. - Matthew Rials, TryBTC

I think so. At Stanford, various friends were poised to drop out or take time off of school to start a venture. I can't help but think that these folks may have missed out on some of the wonders of American college life. - Giancarlo Daniele, Drive Pulse

You're never too young to start a company. I started my first company when I was in Grade 10 in high school. My former Co-Founder, David Kim, and I started a web design firm. Slowly, our client base grew, but we were tired of all of their rules. We decided to scratch our own itch. We ended up launching Draftboard for the designer community [2] in Grade 12. That just shows you how young we were in our ventures. - William Zhou, Planboard

We certainly plan to carry on our project as we transition back to Stanford, once summer has ended. We are very passionate about the notion of spreading Bitcoin to the world and easing the average user's transition into the new currency, and we will continue to work on TryBTC for as long as that takes. We have already raised enough money to keep things running through school, and our investment terms allow for us to remain enrolled in classes. - Matthew Rials, TryBTC

Absolutely. During this summer we’ve had amazing traction with Contastic – our mobile CRM product. The team has grown from 1 person (just me) to six during the 10 weeks. Together, we’ve been able to build a complete product and land pilots at several fortune 500 companies. With the support of Lightspeed and our early customers we’ve been able to develop a truly unique product that will improve the lives of salespeople worldwide. - Cy Khormaee, Contastic

There are few more rewarding ways to spend working hours than to directly think up and build products and wait to see how people use them. You can't usually do this at a traditional internship. - Giancarlo Daniele, Drive Pulse

There's nothing in the world like working for yourself — no pointy haired boss, no managers — just complete control over how you spend your time and what you make of your life. Starting a company is a high-stress, high-risk decision, but it's also high in learning, impact, and fun. We don't wish that we were doing anything else. - Feross Aboukhadijeh, peerCDN

While its true that I became a better programmer, the majority of what I learned this summer would fall into the "professional development" category. There are an astonishing number of soft skills that are absolutely crucial to managing a company, and the people that work for it. 

For instance, taking a product from prototype to production involves managing relationships with hardware designers and manufacturers, electronics designers and manufacturers, packaging designers, retailers, your own internal sales team, your product development team of engineers, your lawyers, your investors, and co-founders. If for example, you didn't know what to look for in a designer when you interviewed your first, you certainly get a better sense by the time you speak to the tenth. Lastly, the most empowering takeaway from the summer is the following: 

I validated that being an entrepreneur is what I was born to do. Whether in this venture or another I have equipped myself with the skills I need to be a successful visionary and leader, and am incredibly grateful for the opportunity Lightspeed gave me to do so. - Aaron Konigsberg, Lapshark via

A different Electronic Security Door Key Circuit Diagram of electronic lock very simple, one and does not need a lot of materials in order to it is manufactured. The right keys of code should be stepped with the right line, so that is activated the optocupler IC2. If from error is stepped switch that does not belong in the combination, then the lock is trapped. In order to we restore the regular operation of lock, it should we press switches S1 or S12. 

Read : Heat Detector Alarm using UM3561 

Switch S1 makes Reset of lock externally and the S12 internally, the door. The Code the circuit as he is connected it is 147 and it can change, very easily, changing the connections in the switches of keyboard. The optocupler IC2, can drive any exterior circuit as Relay etc, ensuring simultaneously electric isolation the two circuits. The circuit can be also supplied from a battery 9V.

Read : Radio Wave Alarm

Part List

    R1-7-9=1Kohm
    R2-3-4-5=100Kohm
    R6 =10Kohm
    R9 =47Kohm
    IC1 = 4066
    IC2 =4N25
    Q1-2=BC550
    S1...11=Push button sw or keyboard
    S12=Push button normal closed
    All resistors is 1/4W 5%

This Digital Electronic Lock Circuit Diagram shown below uses 4 common logic ICs to allow controlling a relay by entering a 4 digit number on a keypad. The first 4 outputs from the CD4017 decade counter (pins 3,2,4,7) are gated together with 4 digits from a keypad so that as the keys are depressed in the correct order, the counter will advance. As each correct key is pressed, a low level appears at the output of the dual NAND gate producing a high level at the output of the 8 input NAND at pin 13.

Read : Cheap Bicycle Alarm Schematics Circuit

Digital Electronic Lock Circuit Diagram

The momentary high level from pin 13 activates a one shot circuit which applies an approximate 80 millisecond positive going pulse to the clock line (pin 14) of the decade counter which advances it one count on the rising edge.

Read : Emergency Light and Alarm Circuit Diagram

A second monostable, one shot circuit is used to generate an approximate 40 millisecond positive going pulse which is applied to the common point of the keypad so that the appropriate NAND gate will see two logic high levels when the correct key is pressed (one from the counter and the other from the key). The inverted clock pulse (negative going) at pin 12 of the 74C14 and the positive going keypad pulse at pin 6 are gated together using two diodes as an AND gate (shown in lower right corner).

Read : Burglar Alarm With Timed Shutoff Circuit Diagram

The output at the junction of the diodes will be positive in the event a wrong key is pressed and will reset the counter. When a correct key is pressed, outputs will be present from both monostable circuits (clock and keypad) causing the reset line to remain low and allowing the counter to advance. However, since the keypad pulse begins slightly before the clock, a 0.1uF capacitor is connected to the reset line to delay the reset until the inverted clock arrives.

Read : 5 Zone alarm Circuit Diagram

The values are not critical and various other timing schemes could be used but the clock signal should be slightly longer than the keypad pulse so that the clock signal can mask out the keypad and avoid resetting the counter in the event the clock pulse ends before the keypad pulse. The fifth output of the counter is on pin 10, so that after four correct key entries have been made, pin 10 will move to a high level and can be used to activate a relay, illuminate an LED, ect. At this point, the lock can be reset simply by pressing any key. The circuit can be extended with additional gates (one more CD4011) to accept up to a 8 digit code.

Read :  Alarm Control Keypad Circuit Diagram

The 4017 counting order is 3 2 4 7 10 1 5 6 9 11 so that the first 8 outputs are connected to the NAND gates and pin 9 would be used to drive the relay or light. The 4 additional NAND gate outputs would connect to the 4 remaining inputs of the CD4068 (pins 9,10,11,12). The circuit will operate from 3 to 12 volts on 4000 series CMOS but only 6 volts or less if 74HC parts are used. The circuit draws very little current (about 165 microamps) so it could be powered for several months on 4 AA batteries assuming only intermittent use of the relay.