Wednesday, December 25, 2013

Simple Radio Wave Alarm

This simple circuit is sure to have the police beating a path to your door- however, it has the added advantage of alerting you to their presence even before their footsteps fall on the doormat.

Simple Radio Wave Alarm Circuit Diagram :



Notes :

  • The circuit transmits on Medium Wave (this is the small problem with the police). IC1a, together with a sensor (try a 20cm x 20cm sheet of tin foil) oscillates at just over 1MHz. This is modulated by an audio frequency (a continuous beep) produced by IC1b. When a hand or a foot approaches the sensor, the frequency of the transmitter (IC1a) drops appreciably.
  • Suppose now that the circuit transmits at 1MHz. Suppose also that your radio is tuned to a frequency just below this. The 1MHz transmission will therefore not be heard by the radio. But bring a hand or a foot near to the sensor, and the transmitters frequency will drop, and a beep will be heard from the radio.
  • Attach the antenna to a multiplug adapter that is plugged into the mains, and you will find that the Medium Wave transmission radiates from every wire in your house. Now place a suitably tuned Medium Wave radio near some wires or a plug point in your house, and an early-warning system is set up.
  • Instead of using the sheet of tin foil as the sensor, you could use a doorknob, or burglar bars. Or you could use a pushbutton and series resistor (wired in series with the 33K resistor - the pushbutton would short it out) to decrease the frequency of IC1a, so activating the system by means of a pushbutton switch. In this case, the radio would be tuned to a frequency just below that of the transmitter.

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Sunday, December 22, 2013

Funk Twang Guitar Effect Box Circuit Diagram

This is an audio effect circuit that give extra oscillation to your guitar, percussive, or semi percussive instruments, you can call it a funk box. This  guitar effect circuit is basically a damped oscillator that is set slightly below its critical oscillation point.  

The oscillator part is constructed by feeding back the output signal through a bandpass circuit, with the center frequency is adjusted by potentiometer R7 to add an extra “twang” , adjustable from low to high pitched timbre. Potentiometer R4 is used to adjust the gain of the oscillator, should be set to damp the oscillation at the desired decay time.  

To adjust it, turn the knob slowly until a steady oscillation occurs, and turn back slightly just before it happens (the oscillation should ceases slowly). Here is the schematic diagram of the circuit.

Funk (Twang) Guitar Effect Box Circuit Diagram
 
Funk (Twang) Guitar Effect Box Circuit Diagram


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Thursday, December 19, 2013

if you have a cell phone that has a GPS on it


Most people are in great pains when they have the feelings of becoming the victim of cheating.
Be careful to go on for only professional sim car spies because there are some that are not worth your penny. Also, be careful to only use this technology for people that are subject or close to

you. The law really frowns at people who breach other peoples privacy.What good will a cell phone GPS locator do for you? You may be wondering why most smart phones today come with navigation

systems and all that. Well, it is simple, it both keeps you on track as well as it helps loved ones to know where you are at any given time. For instance, if you find yourself in a tight corner and

you cannot tell how you got there, if you have a cell phone that has a GPS on it, you can retrace your footsteps and get back on track in no time rather than going round in circles. Also, if at all

you delay and cant get home when you should, your family and friends will be able to know where you are and therefore will not worry so much.
Accessible entirely from the comfort of your own computer, cell phone spy software makes keeping tabs on your loved one simple. Installation is relatively easy as well-all you need to do is create

an information account online through their website, follow the directions, and reboot the phone. In most cases it only takes a few minutes. Once installed, youll be able to monitor the phone

immediately. There is no limit as to how much you can use the software, and there is no need for upgrades or reinstallations.
You can learn more about how to catch cheating girlfriend by reading up on reviews. These, for example, can tell you if the software in question is compatible with Blackberry phones, iPhones,

Symbian S60, Nokia, Windows Mobile, smartphones, and other mobiles on the market today. The more versatile, the better-it means that you can install the software on more than one phone. This makes

it so that if your girlfriend uses a spare, you can still see what shes up to.
Well not anymore! You can use cell phone tracking software to find out EXACTLY what she is saying to everyone she sends a text to, and shell never even know youre watching her. She wont even

know the software is installed on her phone, because it is virtually undetectable. She wont see that its installed. She wont even see that its running. And it will send all of the information

stored in her phone to a remote server, without making any noise or alerting her that its doing it.
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