0 Your PC Needs Some Illumination

Try to lighten up you PC by using LED flex lights to surround the casing. The result will be much appreciated when the room is dark. The chain is housed in rubber plastic which makes more light to be projected out right angles as if some miracle is happening inside the PC.

You can choose which color to use or what you wish to blend with the design of your room. The LED strips are very flexible and customizable which makes them popular. It is very easy to install these strips by using Velcro strips of adhesive backing. You may also use the LED strips in any part of your room like the hairdresser mirror. Click here to visit the project page.

Detail: Your PC Needs Some Illumination

0 USB Keyboard Made from Old Typewriter

Looking for a unique gift? Here’s an antique typewriter which has been modified to function as a USB Keyboard for PC, Mac, or even iPad. That’s very cool, isn’t it?

In the world of obsolescence, this USB typewriter is a groundbreaking innovation. It does not change the outward appearance of the typewriter and is easy to install since there is no messy wiring. The 3 components of the USB typewriter are the Sensor board, the USB switches, and the Reed Switches.

It works like a regular typewriter with all letters, numerals, and punctuation marks as well as shift, space, and return carriage. It’s a better addition to your home office.

Detail: USB Keyboard Made from Old Typewriter

0 Bluetooth Keyboard Controls Dancing Hexapod

Presently, production of robots of different types and functions are rapidly created to help people make their life easier. We can even imagine how the world would look like on the next decade to come. That is – robots do most of the work that people used to do.

Most of the bots in the market are not controlled by Bluetooth except this bot. It’s amazing how this bot dances while controlling the Bluetooth keyboard and a lot of fun to watch for robot fanatics.

In spite the advantages of bots, it can shut down if operation failed therefore failure on its task. Then back to basics must always be a backup.

Detail: Bluetooth Keyboard Controls Dancing Hexapod

0 Modded PC Inspired With Frank Lloyd Wright

You think you already see all the possible case mods? This mod was inspired by the work of the famous Fallingwater architect Frank Lloyd Wright.

The inspired drink bar cantilevered roofs from teak, mahogany highlights, the Cherokee red and covered wagon code colors it is enough to architecture nerd powerlessness. Its fine styling sports has an Intel Core i7-875 GB on Mini-ITX motherboard, with 8 GB of system memory. It has a 256 GB SSD with a 2 TB hard drive.

This desktop cases don’t really tend to get hot, just the components and definitely wouldnt be worried about a fire-hazard. The top looks like it has pretty good airflow too.

Detail: Modded PC Inspired With Frank Lloyd Wright

0 USB Enabled Remote Control

The objective of a remote control is to have the ability to operate a device from a certain distance. Nevertheless, remote controls usually are in places where we need to move around to find. This makes the remote totally useless as you may have used that time and energy to operate the device personally. If we take into account the limited reach that remote have, along with the fact that they are battery operated, we have an obsolete technology. All this can be fixed by developing a new remote control system.

A lot of designs have been completed on systems that operate by clapping. But they have some disadvantages. Such as the fact that they work over only one sound or command. Another fact is that daily activities must be interrupted to give a command.

A whistling command system has been developed to control domestic devices. It works by detecting the sound peaks that are uniquely produced by whistles. Sound from each whistle is processed to give the order to the device.

The sound is received by a mic placed in the room. The microphone is connected to a USB device that transfers the information to a Linux operated computer. Once the command is recognized, the computer sends it to the device.

Detail: USB Enabled Remote Control

0 Cross-Linking With Two Patch Cables

In networks, the supremacy of coax cable is a thing of the past. Nowadays, Ethernet connections are made using UTP cables. The BNC plug has yielded to the 8-way RJ45 plug. Previously, coax cables were daisy-chained from computer to computer and terminated at the two ends using 50-_ resistors, but modern networks use central ‘socket boxes’ (switches and/or hubs) to interconnect everything. The connections between the hubs and the computers are made using patch cables having the same sequence of leads in the RJ45 connectors at each end. For making a direct connection between two computers without using a hub or switch, a ‘crossover cable’ is used.




Such a cable has the leads cross-linked in order to allow the two computers to directly communicate with each other. If there are problems with the network, it can be handy to be able to directly interconnect twocomputers, or directly connect a computer to a cable or ADSL modem without using a hub or switch. A long crossover cable is not always available, and shoving around computers is not an attractive alternative. Consequently, we can use a dual RJ45 wall outlet box to construct an adapter, which can be used to interconnect the two patch cables coming from the equipment in question. This outlet box must be wired to create a cross-linked connection. This is done by making the following internal connections:

• 1 → 3
• 2 → 6
• 3 → 1
• 4 → 4
• 5 → 5
• 6 → 2
• 7 → 7
• 8 → 8

Detail: Cross-Linking With Two Patch Cables

0 Simple LCD Module in 4-bit Mode

In many projects use is made of alphanumeric LCDs that are driven internally by Hitachi’s industry-standard HD44780 controller. These displays can be driven either in 4-bit or 8-bit mode. In the first case only the high nibble (D4 to D7) of the display’s data bus is used. The four unused connections still deserve some closer attention. The data lines can be used as either inputs or outputs for the display. It is well known that an unloaded output is fine, but that a floating high-impedance input can cause problems. So what should you do with the four unused data lines when the display is used in 4-bit mode? This question arose when a circuit was submitted to us where D0-D3 where tied directly to GND (the same applies if it was to +5 V) to stop the problem of floating inputs.

The LCD module was driven directly by a microcontroller, which was on a development board for testing various programs and I/O functions. There was a switch present for turning off the enable of the display when it wasn’t being used, but this could be forgotten during some experiments. When the R/Wline of the display is permanently tied to GND (data only goes from the microcontroller to the display) then the remaining lines can safely be connected to the supply (+ve or GND). In this application however, the R/Wline was also controlled by the microcontroller. When the display is initialised correctly then nothing much should go wrong. The data sheet for the HD44780 is not very clear as to what happens with the low nibble during initialisation.

After the power-on reset the display will always be in 8-bit mode. A simple experiment (see the accompanying circuit) reveals that it is safer to use pull-down resistors to GND for the four low data lines. The data lines of the display are configured as outputs in this circuit (R/Wis high) and the ‘enable’ is toggled (which can still happen, even though it is not the intention to communicate with the display). Note that in practice the RS line will also be driven by an I/O pin, and in our circuit the R/W line as well. All data lines become high and it’s not certain if (and if so, for how long) the display can survive with four shorted data lines. The moral of the story is: in 4-bit mode you should always tie D0-D3 via resistors to ground or positive.

Author: L. Lemmens
Copyright: Elektor Electronics

Detail: Simple LCD Module in 4-bit Mode

0 Usefull Infrared Remote Control Extender

This ultra-simple remote control extender is ideal for use with a hidden video recorder. The recorder is a Panasonic NV-SD200 and is used as part of a camera surveillance system. A PICAXE-08-based circuit is used to detect events and control the recorder. It also flashes a LED near the monitor to indicate the number of events since last viewing.

Strangely, the NV-SD200 model refused to work with a number of commercial infrared remote control extenders, hence the need for this design. As a bonus, it uses less power than a traditional extender (no plugpacks) and the remote can still be used in the normal manner.

As shown, an additional 5mm infrared LED is mounted directly in front of the equipment to be controlled. This is cabled back to a convenient location near the monitor and terminated in a 3.5mm plug.

To modify the remote control unit, break the circuit to the anode of the existing infrared LED and wire in a 3.5mm headphone socket. In most cases, the LED will be accessible without dismantling the circuit board. The purpose of the socket is to allow the existing infrared LED to operate normally when the jack is unplugged.

If the socket won’t fit inside the case, then a very short flying lead with a moulded in-line socket can be used instead. By using light-duty figure-eight cable, the transmitting LED could be 30m or more from the hand-held remote control without problems.

Detail: Usefull Infrared Remote Control Extender

0 Simple IR Remote Control Extender Circuit Diagram

Description:
An Infra Red wired Repeater circuit to control appliances from a remote location.

IR Remote Control Extender Circuit Diagram

Parts List:
R1: 1k Resistor (1)R2: 3.3k Resistor (1)
R3: 10k Resistor (1)
R4: 15k Resistor (1)
R5: 2k2 Resistor (1)
R6: 470R Resistor (1)
R7: 47R Resistor (1) 0.5 Watt
PR1: 4.7k Preset (1)
C1,C3: 47u Elect(2)
C2: 1n Polyester 5% or better (1)
C4: 100u Elect(1)
Z1: 5V1 Zener (1)
Q1: BC549C or BC109C or 2N2222 (1)
Q2: BC337 or BC549 or ZTX450 (1)
IC1 : TSOP1738
IC2: 555 or 7555 (1)
LED1 5mm RED (1)
LED2,3 IR diode TIL38 or similar (2)

Alternatives to IC1 :
Everlight IR receiver module ELIRM 8621
Harrison electronics IR1
Vishay TSOP 1838
Radio Shack 276-0137
Sony SBX 1620-12
Sharp GP1U271R Notes:
The signal emitted by an IR remote control contains two parts, the control pulses and a modulated carrier wave. The control pulses are used to modulate the carrier, a popular modulation frequency being 36 and 42KHz. The signal is radiated by an IR diode, typical wavelengths in the 850 and 950 nm region of the electromagnetic spectrum. Although this light is invisible to the human eye, it can be seen as a bright spot with a camcorder or digital camera.

In this circuit, the TSOP1738 IR module removes the carrier leaving only the slower control pulses ( 1 - 3KHz) which appear at the output. R1, C1 and Z1 form a smoothed 5 Volt supply for the IR module. Under quiescent conditions (no input signal) the output of the IR module is high. Transistor Q1 will be on, resulting in a low collector voltage, restting the 555 oscillator. Q1 also acts as a level shifter, converting the 5 Volt output signal to 12 Volts for the 555 timer. When an IR signal is received, decoded control pulses turn Q1 off and on. Each time Q1 turns off, pin 4 of the 555 timer goes high and an oscillation will be produced for the duration of each data pulse.

The 555 is wired as an equal mark/space ratio oscillator, the timing resistor R4, being connected back to the output of the timer, pin 3. The timing capacitor C2 is the other component in the timing chain. The pulse duration at pin 3 is defined as:-

T = 1.4 R4 C2

As the timing is crucialthe capacitor should have a tolerance of 5% or better and the power supply should be regulated. To allow for tolerance in components a 4k7 preset resistor is wired in series with R4. This adjustment allows R4 to be 15k to 19.7K creating output pulses of 21us and 27.58 us. As frequency is the reciprocal of periodic time then the oscillator adjustment is from 36.2Khz to 47KHz, allowing fine tuning for almost any appliance.

The final output stage uses a BC337 transistor in emitter follower. The output pulse will not be inverted, and the current through the IR photo emitters is around 30 mA dc. This is of course an average value, measured with a digital multimeter. The red led as always, is a visible indication that an input signal has been received. The circuit may be modified to use a fixed resistor in the timing chain as shown below. In this example a voltage regulator is also recommended to prevent changes in supply voltage altering the output pulse.

Setup and Testing:
Remove LED 2 and 3 and apply power. With no input signal LED 1 should be off. Press a button on a remote control in the same room as the circuit. LED 1 should flicker. If all is well, connect LED's 2 and 3 and point them in the direction of the appliance (TV or VCR etc). The cable to the LED's can exceed 100 metres if necessary, ordinary loudspeaker cable or bell wire is suitable. Set preset PR1 midway initially, it should work for all equipment. Most equipment is tolerant to within 5% so if you have for example a video that works at 42kHz and a TV that works at 38Kz tuning the modulation to 40KHz should allow both devices to operate. Any troublesome equipment, for example an Echostar receiver repeatedly press abutton on the handset while tuning PR1, you will find that it operates at some point. One IR LED may be used in place of LED2 & 3, but if there are two appliance in the same room, but in different locations, LED 2 can be aimed at a video, while LED3 aimed at a CD player for example. Below is how I discretely placed a photo emitter and plastered it directly into the wall:

Modifications:
An alternative output configuration is shown below. This uses a MOSFET to replace the original BC337 transistor. My thanks to Pete Griffiths for this modification and diagram.

Compatability:
If you make either the Mark 3 or 4 circuit please let me know if it works and the make and model of your remote control. I will add this to the database of compatible handsets below:-  link

Aiwa RC-ZVR01
Denon RC 554
Denon RC 921
Denon RC 924
Echostar T22605AA-00 * troublesome required careful tuning of PR1 to work
Kameleon One for all remote (URC-8060) Goodmans 97P1R2CPA1
Grundig SRC2
JVC LP20878-002
Matsui 28WN04
Mitsubishi 290P103A10
Mitsubishi EUR647003
NAD HTR2 (multi remote)
One for All 9910
Panasonic EUR511200
Philips RC6512
Pioneer AXD7323
Pioneer DV444
Pioneer VXX2801
Radioshack 1995
Saisho VR3300X
Sony RM-533
Sony RM-887
Sony RMT-V240
Sony RM-S325
Sony RM-DX50
Sony RM-U215
Sony RM-839
Sony RM-SCEX1
Sony RM-S336
Sony RM-D43M
Sony VCR
Technics EUR64713

Detail: Simple IR Remote Control Extender Circuit Diagram