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Here is the circuit diagram of simple but highly effective TV remote jammer circuit. Most of the TV remotes have 38KHz operating frequency. A flood of IR beams in the same frequency can easily confuse the TV receiver and this is the operating principle of our jammer. The circuit is nothing but an astable multivibrator based on NE555 IC. The output of NE555 is amplified using a PNP transistor SK100 to drive the IR LEDs. Not only TV remotes, but any IR remotes operating in the 38KHz frequency region can be also jammed by using this circuit.
Circuit diagram.
Notes.
The circuit can be assembled on a Vero board.
Use a 9V PP3 battery for powering the circuit.
Mount the IC on a holder.
POT R4 can be adjusted to exactly match the jammer’s frequency to the remotes frequency. This adjustment is very essential for effective jamming.
Contact Lenses with “The Terminator” Mode!!
In the movie “The Terminator”, we see Arnold Schwarzenegger check out the complete profile of the subject he is about to face. A similar technology has been developed by Babak Parviz, an electrical engineer at the University of Washington.
Babak designed a lens that can be used to display a single pixel at a time. This display can be switched on and turned off through a wireless medium. The lens consists of an IC which stores the energy, along with an LED that shoots the light towards the eyes. But, the lens is not capable of intercepting objects that are very close to the eye. This problem is overcome by placing some counter lenses in between the LED and the eye. The same principle can be simply tested by placing an appropriate magnifying glass to see your finger that is placed very near to your eye.
Till now, the lens has only been designed to display one pixel. But, there may be a time when you could use the lenses to bring together all the displays you interact with on a daily basis – your PC, fridge, chair, mobile – into one personal display in your eye. Later, the same technology could be modified to bring in virtual images into the real world. For example, you could design the interior of your plain room with paintings, furniture and so on.
As show in the figure above, the LED part of the lens is opaque, but these little dark spots shouldn’t make the images unnoticed. A control circuit and a radio are also shown. They are used to gather the energy from a transmitter kept at the edge of the lens and convey the information to the outside. The design is made sleek enough in such a way that they do not block the view in any way. The lens was first tested on animals and they have proved to be working perfectly without any safety problems. The officials are waiting for an approval to test it on humans.
If this technology does become famous, the researchers will have to take special care in protection of the software side. That is, someone could easily pop up spams inside the control circuitry of the lens and block the view of a person, who may be busy driving his car.
Waterless Washing Machine Cleans Laundry Through Magnetic Levitation
New inventions have made strainful works always easier for people. Let us take an example of a washing machine. In early days, people used to wash their own clothes by hand and scrub all the dirt away using a brush and detergent. Later, the washing machine was invented, which simplified laundry cleaning. The device was further developed to produce semi-cleaners and lately fully automatic washing machines.
A new concept has been introduced by a a designer named Elie Ahovi, which works under the principle of magnetic levitation.
The device, named as “Laundry Orb” consists of a spherical drum that cleans clothes by scrubbing them using dry ice, instead f water. The spherical drum is basically a ring filled with batteries. These batteries produces magnetic levitation inside the ring. To levitate, a super-conductive metal laundry basket is introduced inside. A low temperature is required inside the ring. This is produced by using liquid nitrogen. A double layered shatterproof glass is also introduced inside. Thus, the whole drum levitates as soon as a magnetic field is produced. The whole process is controlled using a touch screen interface.
The dry ice is introduced inside the ring at supersonic speeds. As soon as it hits the dirty clothes, the carbon dioxide interacts with the dirt and separates them from the clothes. The dirt is then collected and filtered out through small pores. The carbon dioxide is then removed and re-frozen. Thus, the clothes are cleaned and dry.
The cleaning process will take only a few minutes. Since no water and soap is used, the clothes are prone to look new without any wear ad tear. The environment can also be protected to a certain extent by saving soap. Besides, we can use the surplus carbon dioxide for something useful.
Though the whole concept sounds interesting, there are certain cons. The removing of carbon dioxide and refreezing it requires a lot of energy.
Stereo headphone amplifier
LM4910 stereo headphone amplifier.
LM4910 belonging to the Boomer series of National Semiconductors is an integrated stereo amplifier primarily intended for stereo headphone applications. The IC can be operated from 3.3V ans its can deliver 0.35mW output power into a 32 ohm load. The LM4910 has very low distortion ( less than 1%) and the shutdown current is less than 1uA. This low shut down current makes it suitable for battery operated applications. The IC is so designed that there is no need of the output coupling capacitors, half supply by-pass capacitors and bootstrap capacitors. Other features of the IC are turn ON/OFF click elimination, externally programmable gain etc.
Circuit diagram.
Stereo headphone amplifier LM4910
Circuit diagram of the LM4910 stereo headphone amplifier is shown above.C1 and C2 are the input DC decoupling capacitors for the left and right input channels. R1 and R2 are the respective input resistors. R3 is the feed back resistor for left channel while R4 is the feed back resistor for the right channel. C3 is the power supply filter capacitor. The feedback resistors also sets the closed loop gain in conjunction with the corresponding input resistors.
Notes.
The IC is available only in SMD packages and care must be taken while soldering.
The circuit can be powered from anything between 2.2V to 5V DC.
The load can be a 32 ohm headphone.
Absolute maximum supply voltage is 6V and anything above it will destroy the IC.
A logic low voltage at the shutdown pins shut downs the IC and a logic high voltage at the same pin activates the IC.
Simple FM transmitter circuit.
Description.
A lot of FM transmitter circuits have been already published here. This just another one, a simple two transistor FM transmitter.The first stage of the circuit is a preamplifier stage based on transistor Q1. This is a collector to base biased amplifier stage where resistor R2 sets the collector current and R1 provided the necessary collector to base bias. C1 is the input DC decoupling capacitor which couples the input audio signal to the Q1 base. C8 is the power supply by-pass capacitor. Next stage is the oscillator cum modulator stage built around transistor Q2. Electrolytic capacitor C2 couples the output of the first stage to the second stage. R3 and R4 are the biasing resistors of Q2. R5 is the emitter resistor of Q2. Inductor L1 and trimmer capacitor C5 forms the tank circuit which is necessary for creating oscillations. The modulated FM signal is available at the collector of Q2 and it is coupled to the antenna using capacitor C9.
Circuit diagram.
Simple FM transmitter circuit
Notes.
The circuit can be powered from anything between 6 to 12V DC.
Using battery for powering the circuit will improve the performance and reduce noise.
A 9V PP3 battery is a good option.
If you are going with a battery eliminator, then it must be well filtered and regulated.
Trimmer C5 can be used for adjusting the transmission frequency.
Antenna can be a 1m copper wire.
L1 can be constructed my making 4 turns of 1mm enameled copper wire on a 10mm diameter plastic former.
Trimmer capacitor C6 can be adjusted for obtaining the maximum range.
Most of the components required for this circuit can be procured from your junk box.
IMAX – The Giant Step to Movies
Let a movie be in 3-D or an ordinary 70mm projection. We have always loved it for the story, sound effects, visual effects, and many other factors. But latest technologies have improved the way in which graphics and other effects have been introduced in each frame. Out of them IMAX is the most popular.
The Fox introduced the first 70mm format, the Fox grandeur in 1929. Later the Cinema scope and vista vision widened the image from 35mm. Then came IMAX with its advanced methods of film projection ever to be seen by anyone. The format was developed by a Canadian company called IMAX corporation, and hence the name. Today, it is estimated that IMAX is available in about 528 theaters in 46 countries. IMAX provides a better resolution and picture stabilization. IMAX Corporation has developed various projectors and standards for delivering a better viewing experience. IMAX has been used since 2002 in various theaters across the world. IMAX 3D is also gaining much popularity recently. Let us now take a look of the various technical aspects of IMAX.
The camera used in IMAX has a much larger frame and hence increases the resolution. IMAX aims at more precision than strength so it uses “ESTAR” base. IMAX format is generally called “15/70” film because of the 15 sprocket – hole or film thickness. For increasing the image area the sound track of the IMAX is recorded separately in another film and is synchronized with the main film. A separate 6 channel 35mm magnetic film which converts directly to analog is used for this purpose. For producing high quality 3D effects, the speakers in IMAX theaters are placed directly behind the screen and around the theater.
Conventional 70mm projectors are not able to produce 586 x magnification. IMAX projectors are pin stabilized which makes the film stable and ensures perfect alignment. The shutter speed of the projector is 20 times faster than the conventional projector and produces a brighter source of light. The light is produced from xenon short arc lamps made of fused quartz and xenon gas at a pressure of 25 atmospheres. The personals operating this projector should be skilled and must wear thick body armor while handling it. The quartz crystals and the xenon gas that produces the light could break easily and hurt the operator.
There are four types of projectors used in IMAX, namely GT (Grant theater), GT 3D (duel rotor), SR (small rotor) and MPX . All these projectors use the 70mm format. Theater construction for IMAX differs with respect to others. The audiences are allowed to site near the screen because of the higher resolution. The size of a standard IMAX screen is 22 x 16.1m.
IMAX 3D is a popular method for 3D vision in theaters . In IMAX 3D two separate cameras are used to generate the effect of 3D. The two cameras represent the right and left eyes. Separate film rolls should be there for each lens. When these two films are projected simultaneously the viewer will get an illusion of reality or a 3D image. The two lenses should be separated by a distance of 64 mm, which is the average distance between the human eyes. For creating 3D illusion the light from the two images are polarized. Eye glasses with left and right lens are polarized to match the projection. These glasses cancel the polarization and thus produce an illusion of 3D. The two projectors alternately display the film at a rate of 48 frames per second. LCD shutter glasses, which contain LCD panels, are used for this purpose and the eye sees only that image it intend to see.
Let us now see the technical specifications of IMAX
IMAX (15/70)
Spherical lenses also known as singlets which has the shape of the surface of sphere are employed in IMAX.
70 mm film is used and with 15 rotations per frame
When viewed from the base side we can see a right-left horizontal rolling stop movement is there
24 frames per second
The aperture of the camera is 70.41 X 52.63 (2.772 X 2.072 inc)
The aspect ratio is 1:44:1
The IMAX is used in various other purposes like Digital media remastering. The conventional films can be converted into IMAX format. The 1995 film Apollo 13 was the first to be converted into IMAX and it was released in 2002. The digital intermediate technology enabled the films shot in 35mm to be shown in IMAX venues. IMAX can undoubtedly be called as the film viewing technology of the future.
TV remote jammer
Description.
Circuit diagram.
Notes.
The circuit can be assembled on a Vero board.
Use a 9V PP3 battery for powering the circuit.
Mount the IC on a holder.
POT R4 can be adjusted to exactly match the jammer’s frequency to the remotes frequency. This adjustment is very essential for effective jamming.
Contact Lenses with “The Terminator” Mode!!
In the movie “The Terminator”, we see Arnold Schwarzenegger check out the complete profile of the subject he is about to face. A similar technology has been developed by Babak Parviz, an electrical engineer at the University of Washington.
Babak designed a lens that can be used to display a single pixel at a time. This display can be switched on and turned off through a wireless medium. The lens consists of an IC which stores the energy, along with an LED that shoots the light towards the eyes. But, the lens is not capable of intercepting objects that are very close to the eye. This problem is overcome by placing some counter lenses in between the LED and the eye. The same principle can be simply tested by placing an appropriate magnifying glass to see your finger that is placed very near to your eye.
Till now, the lens has only been designed to display one pixel. But, there may be a time when you could use the lenses to bring together all the displays you interact with on a daily basis – your PC, fridge, chair, mobile – into one personal display in your eye. Later, the same technology could be modified to bring in virtual images into the real world. For example, you could design the interior of your plain room with paintings, furniture and so on.
As show in the figure above, the LED part of the lens is opaque, but these little dark spots shouldn’t make the images unnoticed. A control circuit and a radio are also shown. They are used to gather the energy from a transmitter kept at the edge of the lens and convey the information to the outside. The design is made sleek enough in such a way that they do not block the view in any way. The lens was first tested on animals and they have proved to be working perfectly without any safety problems. The officials are waiting for an approval to test it on humans.
If this technology does become famous, the researchers will have to take special care in protection of the software side. That is, someone could easily pop up spams inside the control circuitry of the lens and block the view of a person, who may be busy driving his car.
Waterless Washing Machine Cleans Laundry Through Magnetic Levitation
New inventions have made strainful works always easier for people. Let us take an example of a washing machine. In early days, people used to wash their own clothes by hand and scrub all the dirt away using a brush and detergent. Later, the washing machine was invented, which simplified laundry cleaning. The device was further developed to produce semi-cleaners and lately fully automatic washing machines.
A new concept has been introduced by a a designer named Elie Ahovi, which works under the principle of magnetic levitation.
The device, named as “Laundry Orb” consists of a spherical drum that cleans clothes by scrubbing them using dry ice, instead f water. The spherical drum is basically a ring filled with batteries. These batteries produces magnetic levitation inside the ring. To levitate, a super-conductive metal laundry basket is introduced inside. A low temperature is required inside the ring. This is produced by using liquid nitrogen. A double layered shatterproof glass is also introduced inside. Thus, the whole drum levitates as soon as a magnetic field is produced. The whole process is controlled using a touch screen interface.
The dry ice is introduced inside the ring at supersonic speeds. As soon as it hits the dirty clothes, the carbon dioxide interacts with the dirt and separates them from the clothes. The dirt is then collected and filtered out through small pores. The carbon dioxide is then removed and re-frozen. Thus, the clothes are cleaned and dry.
The cleaning process will take only a few minutes. Since no water and soap is used, the clothes are prone to look new without any wear ad tear. The environment can also be protected to a certain extent by saving soap. Besides, we can use the surplus carbon dioxide for something useful.
Though the whole concept sounds interesting, there are certain cons. The removing of carbon dioxide and refreezing it requires a lot of energy.
Stereo headphone amplifier
LM4910 stereo headphone amplifier.
LM4910 belonging to the Boomer series of National Semiconductors is an integrated stereo amplifier primarily intended for stereo headphone applications. The IC can be operated from 3.3V ans its can deliver 0.35mW output power into a 32 ohm load. The LM4910 has very low distortion ( less than 1%) and the shutdown current is less than 1uA. This low shut down current makes it suitable for battery operated applications. The IC is so designed that there is no need of the output coupling capacitors, half supply by-pass capacitors and bootstrap capacitors. Other features of the IC are turn ON/OFF click elimination, externally programmable gain etc.
Circuit diagram.
Stereo headphone amplifier LM4910
Circuit diagram of the LM4910 stereo headphone amplifier is shown above.C1 and C2 are the input DC decoupling capacitors for the left and right input channels. R1 and R2 are the respective input resistors. R3 is the feed back resistor for left channel while R4 is the feed back resistor for the right channel. C3 is the power supply filter capacitor. The feedback resistors also sets the closed loop gain in conjunction with the corresponding input resistors.
Notes.
The IC is available only in SMD packages and care must be taken while soldering.
The circuit can be powered from anything between 2.2V to 5V DC.
The load can be a 32 ohm headphone.
Absolute maximum supply voltage is 6V and anything above it will destroy the IC.
A logic low voltage at the shutdown pins shut downs the IC and a logic high voltage at the same pin activates the IC.
Simple FM transmitter circuit.
Description.
A lot of FM transmitter circuits have been already published here. This just another one, a simple two transistor FM transmitter.The first stage of the circuit is a preamplifier stage based on transistor Q1. This is a collector to base biased amplifier stage where resistor R2 sets the collector current and R1 provided the necessary collector to base bias. C1 is the input DC decoupling capacitor which couples the input audio signal to the Q1 base. C8 is the power supply by-pass capacitor. Next stage is the oscillator cum modulator stage built around transistor Q2. Electrolytic capacitor C2 couples the output of the first stage to the second stage. R3 and R4 are the biasing resistors of Q2. R5 is the emitter resistor of Q2. Inductor L1 and trimmer capacitor C5 forms the tank circuit which is necessary for creating oscillations. The modulated FM signal is available at the collector of Q2 and it is coupled to the antenna using capacitor C9.
Circuit diagram.
Simple FM transmitter circuit
Notes.
The circuit can be powered from anything between 6 to 12V DC.
Using battery for powering the circuit will improve the performance and reduce noise.
A 9V PP3 battery is a good option.
If you are going with a battery eliminator, then it must be well filtered and regulated.
Trimmer C5 can be used for adjusting the transmission frequency.
Antenna can be a 1m copper wire.
L1 can be constructed my making 4 turns of 1mm enameled copper wire on a 10mm diameter plastic former.
Trimmer capacitor C6 can be adjusted for obtaining the maximum range.
Most of the components required for this circuit can be procured from your junk box.
IMAX – The Giant Step to Movies
Let a movie be in 3-D or an ordinary 70mm projection. We have always loved it for the story, sound effects, visual effects, and many other factors. But latest technologies have improved the way in which graphics and other effects have been introduced in each frame. Out of them IMAX is the most popular.
The Fox introduced the first 70mm format, the Fox grandeur in 1929. Later the Cinema scope and vista vision widened the image from 35mm. Then came IMAX with its advanced methods of film projection ever to be seen by anyone. The format was developed by a Canadian company called IMAX corporation, and hence the name. Today, it is estimated that IMAX is available in about 528 theaters in 46 countries. IMAX provides a better resolution and picture stabilization. IMAX Corporation has developed various projectors and standards for delivering a better viewing experience. IMAX has been used since 2002 in various theaters across the world. IMAX 3D is also gaining much popularity recently. Let us now take a look of the various technical aspects of IMAX.
The camera used in IMAX has a much larger frame and hence increases the resolution. IMAX aims at more precision than strength so it uses “ESTAR” base. IMAX format is generally called “15/70” film because of the 15 sprocket – hole or film thickness. For increasing the image area the sound track of the IMAX is recorded separately in another film and is synchronized with the main film. A separate 6 channel 35mm magnetic film which converts directly to analog is used for this purpose. For producing high quality 3D effects, the speakers in IMAX theaters are placed directly behind the screen and around the theater.
Conventional 70mm projectors are not able to produce 586 x magnification. IMAX projectors are pin stabilized which makes the film stable and ensures perfect alignment. The shutter speed of the projector is 20 times faster than the conventional projector and produces a brighter source of light. The light is produced from xenon short arc lamps made of fused quartz and xenon gas at a pressure of 25 atmospheres. The personals operating this projector should be skilled and must wear thick body armor while handling it. The quartz crystals and the xenon gas that produces the light could break easily and hurt the operator.
There are four types of projectors used in IMAX, namely GT (Grant theater), GT 3D (duel rotor), SR (small rotor) and MPX . All these projectors use the 70mm format. Theater construction for IMAX differs with respect to others. The audiences are allowed to site near the screen because of the higher resolution. The size of a standard IMAX screen is 22 x 16.1m.
IMAX 3D is a popular method for 3D vision in theaters . In IMAX 3D two separate cameras are used to generate the effect of 3D. The two cameras represent the right and left eyes. Separate film rolls should be there for each lens. When these two films are projected simultaneously the viewer will get an illusion of reality or a 3D image. The two lenses should be separated by a distance of 64 mm, which is the average distance between the human eyes. For creating 3D illusion the light from the two images are polarized. Eye glasses with left and right lens are polarized to match the projection. These glasses cancel the polarization and thus produce an illusion of 3D. The two projectors alternately display the film at a rate of 48 frames per second. LCD shutter glasses, which contain LCD panels, are used for this purpose and the eye sees only that image it intend to see.
Let us now see the technical specifications of IMAX
IMAX (15/70)
Spherical lenses also known as singlets which has the shape of the surface of sphere are employed in IMAX.
70 mm film is used and with 15 rotations per frame
When viewed from the base side we can see a right-left horizontal rolling stop movement is there
24 frames per second
The aperture of the camera is 70.41 X 52.63 (2.772 X 2.072 inc)
The aspect ratio is 1:44:1
The IMAX is used in various other purposes like Digital media remastering. The conventional films can be converted into IMAX format. The 1995 film Apollo 13 was the first to be converted into IMAX and it was released in 2002. The digital intermediate technology enabled the films shot in 35mm to be shown in IMAX venues. IMAX can undoubtedly be called as the film viewing technology of the future.
