Description.
Here is the circuit diagram of a powerful 12V regulator that can deliver up to 15 A of current.The common voltage regulator IC 7812(IC1) is used to keep the voltage at steady 12V and three TIP 2599 power transistors in parallel are wired in series pass mode to boost the output current. The 7812 can provide only up to 1A and rest of the current is supplied by the series pass transistors. The 15A bridge B1 does the job of rectifying the stepped down AC input. The capacitor C1, C2 and C3 act as filters. The 1A fuse F1 protects the IC1 from over current in case if the pass transistors fail. The 15A fuse F2 protects the entire circuit (especially the pass transistors) from over current.

With high current transformer, power transistors and high current bridge the circuit is a bit costly and you may try this only if there is a serious need.

Circuit diagram with Parts list.

Notes.

• Assemble the circuit on a good quality PCB.
• The T1 can be a 230V AC primary, 18V secondary, 15A type transformer.
• The B1 can be a 15A bridge.
• If 15A Bridge is not available, make one using four RURG1520CC diodes.
• The IC1 and transistors must be mounted on heat sinks.

“Sleek&Sexy” in design-thats what Lenovo IdeaCentre A600 is @ first look.

This revolutionary desktop in the age of tablets and notebooks features 21.5″ screen for multimedia-holics along with Blu-Ray disc and other usual system components.

Features are:

Processor: Intel Core 2 Duo

Memory: 4GB of DDR3 memory

Hard Disk: Upto 1TB (available)

Additional Luxury:

In addition to the usual features like Harddisk, Memory,Processor and all such stuffs, IdeaCentre A600 features brand new add-on which makes it distinct!

1. Has a nifty 4-in-1 remote control that acts as an air mouse

2. Includes a VOIP Handset

3. Has a MediaCentre Remote

4. Uses 1920×1080 HD resolution for screen

5. Uses the glorified VeriFace technology-which uses facial images as login passwords for your computer.

This brand new PC’s are available from rates starting @ $699!

Drawbacks:

1. It looks like a copy of the “APPLE” Mac style! Screen & system components as one module-but this one is worth for the price! I hope.

Advantages:

1. For the entertainment enthusiast, the all-in-one offers a 16:9 aspect ratio screen with full HD resolution while the integrated speaker system with bass sub-woofer and Dolby Home Theater audio certification completes the home cinema experience.

RATING:

3.4/5 – Overall

4.1/5 – Design

4/5 – For Components Inside & Performance

Write your opinions as comments!

Description.

Here is a simple 3 input mic mixer circuit using the popular uA 741 ICs. Four 741s are used here.IC1, IC2, IC3 are used as preamplifiers. They produce a gain of around 40 decibel to the individual input signals. The IC4 is wired as a summing amplifier to add the signals from three preamplifiers.IC4 also gives a gain of around 5decibel to the final output signal. Total gain of the system is around 45decibel.

Circuit diagram with Parts list.

Notes.

• Assemble the circuit on a good quality PCB.
• A +15/-15 V DC dual power supply is needed for powering the circuit.
• All inputs and output must be connected with respect to the ground.
• ICs must be mounted on holders.
• Electrolytic capacitors C1, C2 and C3  must be rated 10V and other capacitors  must be 30V.

Six pin Microcontrollers from Atmel-AVR ATtiny10

The latest AVR ATtiny10 is highly suitable for large volume market applications.

AVR ATtiny10 has 1kilobytes of programmable flash memory, 32 bytes of internal Static Ram,  8-bit Analog to Digital converter, a 16-bit timer with Pulse Width Modulation, 12 MIPS of processing throughput and an analog comparator.Using the AVR CPU, this device is supposed to give 6 times performance of any other similar size & cost device available in the market.

Atmel says “If your application needs higher processing power with lower current consumption, AVR ATtiny10 is the right soultion”

All tinyAVR microcontrollers use the standard AVR microcontroller development tools. The AVR Studio AVR integrated development environment is available free of charge on Atmel’s website. Samples of this microC is now available at a very small price of $0.35 for 10k units.

How AVR ATtiny10 ensures low power consumption?

This device with high processing efficiency reduces the time in active mode and more time will be spent in power saving sleep modes. In addition to this, Atmels picopower technology is used in this device which ensures low power consumption.

Key Parameters:

Flash (Kbytes)  – 1
SRAM (Bytes) -  32
Max I/O Pins  – 4
F.max (MHz)  – 12
Vcc (V)             – 1.8-5-5V
Analog Comparator   – Yes

Description.

Here is the circuit diagram of a simple two transistor tone controller circuit. This circuit is based on the famous Baxandal tone control design. The transistor Q1 is wired an emitter follower to provide sufficient current gain and input impedance. The second transistor is used to voltage amplify the signal in. The network of resistance and capacitors connected between emitter of Q1 and base of Q2 is used to control the tone. Variation in the value of these components varies the audio response of the system.This circuit can provide a maximum attenuation and boost of 10decibel on 10KHz and 60Hz frequency ranges.

Circuit diagram with Parts list.

Notes.

• The circuit can be powered from 12V DC.
• The input and output must be connected with respect the ground.
• POT R5 can be used to control bass.
• POT R8 can be used to control treble.
• All electrolytic capacitors must be rated at least 12V.