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Elektor 10-2009

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Microcontrollers fundamentals and applications with PIC

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Control 2-2009

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4th Generation Nuclear Nanotech Weapons

The Military Impact of Nanotechnology Nanotechnology, i.e., the science of designing microscopic structures in which the materials and their relations are machined and controlled atom-by-atom, holds the promise of numerous applications.

Lying at the crossroads of engineering, physics, chemistry, and biology, nanotechnology may have considerable impact in all areas of science and technology. However, it is certain that the most significant near term applications of nanotechnology will be in the military domain. In fact, it is under the names of ‘micromechanical engineering’ and ‘microelectromechanical systems’ (MEMS) that the field of nanotechnology was born a few decades ago – in nuclear weapons laboratories.

A primary impetus for creating these systems was the need for extremely rugged and safe arming and triggering mechanisms for nuclear weapons such as atomic artillery shells. In such warheads, the nuclear explosive and its trigger undergo extreme acceleration (10,000 times greater than gravity when the munition is delivered by a heavy gun).

A general design technique is then to make the trigger’s crucial components as small as possible.5 For similar reasons of extreme safety, reliability, and resistance to external factors, the detonators and the various locking mechanisms of nuclear weapons were increasingly designed as more and more sophisticated microelectromechanical systems.

Consequently, nuclear weapons laboratories such as the Sandia National Laboratory in the US are leading the world in translating the most advanced concepts of MEMS engineering into practice.

A second historical impetus for MEMS and nanotechnology, one which is also over thirty years old, is the still ongoing drive towards miniaturisation of nuclear weapons and the related quest for very-low yield nuclear explosives which could also be used as a source of nuclear energy in the form of controlled microexplosions.

Such explosions (with yields in the range of a few kilograms to a few tons of high-explosive equivalent) would in principle be contained – but they could just as well be used in weapons if suitable compact triggers are developed.

In this line of research, it was soon discovered that it is easier to design a micro-fusion than a micro-fission explosive (which has the further advantage of producing much less radioactive fallout than a micro-fission device of the same yield). Since that time, enormous progress has been made, and the research on these micro-fusion bombs has now become the main advanced weapons research activity of the nuclear weapons laboratories, using gigantic tools such as the US National Ignition Facility (NIF) and France’s Laser Mégajoule. The tiny pellets used in these experiments, containing the thermonuclear fuel to be exploded, are certainly the most delicate and sophisticated nano-engineered devices in existence.

A third major impetus for nanotechnology is the growing demand for better materials (and parts made of them) with extremely well characterised specifications. These can be new materials such as improved insulators which will increase the storage capacity of capacitors used in detonators, nano-engineered high-explosives for advanced weaponry, etc. But they can also be conventional materials of extreme purity, or nano-engineered components of extreme precision.

The final major impetus for MEMS and nanotechnology, which has the greatest overlap with non-military needs, is their promise of new high-performance sensors, transducers, actuators, and electronic components. The development of this field of applications is expected to replicate that of the micro-electronic industry, which was also originally driven by military needs, and which provides the reference for forecasting a nano-industrial boom and a financial bonanza.

There are, however, two major differences.

First, electronic devices which can be manufactured in large quantities and at low cost are essentially planar, while MEMS are three-dimensional devices which may include moving parts.

Second, the need for MEMS outside professional circles (medical, scientific, police, military) is quite limited, so that the market might not be as wide as expected. For example, the detection and identification of chemical or biological weapon threats through specificity of molecular response may lead to all sorts of medical applications, but only to few consumer goods.

Near and Long-Term Applications and Implications of Nanotechnology

Considering that nanotechnology is already an integral part of the development of modern weapons, it is important to realise that its immediate potential to improve existing weapons (either conventional or nuclear), and its short-term potential to create new weapons (either conventional or nuclear), are more than sufficient to require the immediate attention of diplomats and arms controllers.

In this perspective, the potential long-term applications of nanotechnology (and their foreseeable social and political implications) should neither be downplayed nor overemphasised.

Indeed, there are potential applications such as self-replicating nano-robots (’nanobots’) which may never prove to be feasible because of fundamental physical or technical obstacles. But this impossibility would not mean that the somewhat larger micro-robots of the type that are seriously considered in military laboratories could never become a reality.

In light of these extant and potential dangers and risks, every effort should be made not to repeat the error of the arms-control community with regard to missile defence. For over thirty years, that community acted on the premise that a ballistic missile defense system will never be built because it will never be sufficiently effective – only to be faced with a concerted attempt to construct such a system! If some treaty is contemplated in order to control or prohibit the development of nanotechnology, it should be drafted in such a way that all reasonable long-term applications are covered.

Moreover, it should not be forgotten that while nanotechnology mostly emphasises the spatial extension of matter at the scale of the nanometer (the size of a few atoms), the time dimension of mechanical engineering has recently reached its ultimate limit at the scale of the femtosecond (the time taken by an electron to circle an atom)

It has thus become possible to generate bursts of energy in suitably packaged pulses in space and time that have critical applications in nanotechnology, and to focus pulses of particle or laser beams with extremely short durations on a few micrometer down to a few nanometer sized targets.

The invention of the ’superlaser’, which enabled such a feat and provided a factor of one million increase in the instantaneous power of tabletop lasers, is possibly the most significant recent advance in military technology. This increase is of the same magnitude as the factor of one million difference in energy density between chemical and nuclear energy.9

Nanotechnological Improvement of Existing Types of Nuclear Weapons

Nuclear weapon technology is characterised by two sharply contrasting demands. On the one hand, the nuclear package containing the fission and fusion materials is relatively simple and forgiving, i.e. rather more sophisticated than complicated.

On the other hand, the many ancillary components required for arming the weapon, triggering the high-explosives, and initiating the neutron chain-reaction, are much more complicated. Moreover, the problems related to maintaining political control over the use of nuclear weapons, i.e. the operation of permissive action links (PALs), necessitated the development of protection systems that are meant to remain active all the way to the target, meaning that all these ancillary components and systems are submitted to very stringent requirements for security, safety, and reliable performance under severe conditions.

The general solution to these problems is to favour the use of hybrid combinations of mechanical and electronic systems, which have the advantage of dramatically reducing the probability of common mode failures and decreasing sensitivity to external factors. It is this search for the maximisation of reliability and ruggedness which is driving the development and application of nanotechnology and MEMS engineering in nuclear weapons science.

To give an important example: modern nuclear weapons use insensitive high-explosives (IHE) which can only be detonated by means of a small charge of sensitive high-explosive that is held out of alignment from the main charge of IHE. Only once the warhead is armed does a MEMS bring the detonator into position with the main charge. Since the insensitive high-explosive in a nuclear weapon is usually broken down into many separate parts that are triggered by individual detonators, the use of MEMS-based detonators incorporating individual locking mechanisms are an important ingredient ensuring the use-control and one-point safety of such weapons.

Further improvements on existing nuclear weapons are stemming from the application of nanotechnology to materials engineering. New capacitors, new radiation-resistant integrated circuits, new composite materials capable to withstand high temperatures and accelerations, etc., will enable a further level of miniaturisation and a corresponding enhancement of safety and usability of nuclear weapons. Consequently, the military utility and the possibility of forward deployment, as well as the potentiality for new missions, will be increased.

Consider the concept of a “low-yield” earth penetrating warhead. The military appeal of such a weapon derives from the inherent difficulty of destroying underground targets.

Only about 15 % of the energy from a surface explosion is coupled (transferred) into the ground, while shock waves are quickly attenuated when travelling through the ground. Even a few megatons surface burst will not be able to destroy a buried target at a depth or distance more than 100-200 meters away from ground zero. A radical alternative, therefore, is to design a warhead which would detonate after penetrating the ground by a few tens of meters or more. Since a free-falling or rocket-driven missile will not penetrate the surface by more than about ten meters, some kind of active penetration mechanism is required. This implies that the nuclear package and its ancillary components will have to survive extreme conditions of stress until the warhead is detonated.

Fourth-Generation Nuclear Weapons

First- and second-generation nuclear weapons are atomic and hydrogen bombs developed during the 1940s and 1950s, while third-generation weapons comprise a number of concepts developed between the 1960s and 1980s, e.g. the neutron bomb, which never found a permanent place in the military arsenals.

Fourth-generation nuclear weapons are new types of nuclear explosives that can be developed in full compliance with the Comprehensive Test Ban Treaty (CTBT) using inertial confinement fusion (ICF) facilities such as the NIF in the US, and other advanced technologies which are under active development in all the major nuclear-weapon states – and in major industrial powers such as Germany and Japan.11

In a nutshell, the defining technical characteristic of fourth-generation nuclear weapons is the triggering – by some advanced technology such as a superlaser, magnetic compression, antimatter, etc. – of a relatively small thermonuclear explosion in which a deuterium-tritium mixture is burnt in a device whose weight and size are not much larger than a few kilograms and litres.

Since the yield of these warheads could go from a fraction of a ton to many tens of tons of high-explosive equivalent, their delivery by precision-guided munitions or other means will dramatically increase the fire-power of those who possess them – without crossing the threshold of using kiloton-to-megaton nuclear weapons, and therefore without breaking the taboo against the first-use of weapons of mass destruction.

Moreover, since these new weapons will use no (or very little) fissionable materials, they will produce virtually no radioactive fallout. Their proponents will define them as “clean” nuclear weapons – and possibly draw a parallel between their battlefield use and the consequences of the expenditure of depleted uranium ammunition.12

In practice, since the controlled release of thermonuclear energy in the form of laboratory scale explosions (i.e., equivalent to a few kilograms of high-explosives) at ICF facilities like NIF is likely to succeed in the next 10 to 15 years, the main arms control question is how to prevent this know-how being used to manufacture fourth-generation nuclear weapons.

As we have already seen, nanotechnology and micromechanical engineering are integral parts of ICF pellet construction. But this is also the case with ICF drivers and diagnostic devices, and even more so with all the hardware that will have to be miniaturised and ‘ruggedised’ to the extreme in order to produce a compact, robust, and cost-effective weapon.

A thorough discussion of the potential of nanotechnology and microelectromechanical engineering in relation to the emergence of fourth-generation nuclear weapons is therefore of the utmost importance. It is likely that this discussion will be difficult, not just because of secrecy and other restrictions, but mainly because the military usefulness and usability of these weapons is likely to remain very high as long as precision-guided delivery systems dominate the battlefield.

It is therefore important to realise that the technological hurdles that have to be overcome in order for laboratory scale thermonuclear explosions to be turned into weapons may be the only remaining significant barrier against the introduction and proliferation of fourth-generation nuclear weapons. For this reason alone – and there are many others, beyond the scope of this paper – very serious consideration should be given to the possibility of promoting an ‘Inner Space Treaty’ to prohibit the military development and application of nanotechnological devices and techniques.

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Introduction to Residential Layout

Introduction to Residential Layout is ideal for students and practitioners of urban design, planning, engineering, architecture and landscape seeking a comprehensive guide to the theory and practice of designing and laying out residential areas.

Mike Biddulph provides a clear and coherent framework from which he offers comprehensive practical advice for designers of housing developments. Referring to a wealth of international examples, this is a richly illustrated, accessible resource covering the whole range of issues that should be considered by
anyone engaging in the planning and design of a new residential scheme.

A successful residential development must work on many levels – financial, social and environmental. This book includes analysis of commercial viability, the importance of place making, environmental sustainability and designing accessibility. Mike Biddulph details successful approaches to designing out crime and maximising permeability as part of an integrated approach to urban design.

Highly illustrated throughout, this work will show you how to turn design aspirations and principles into practical design solutions. Written without preconceptions, Introduction to Residential Design
highlights the strengths and weaknesses of particular design solutions to encourage both depth of thought and creativity.

Mike Biddulph is Senior Lecturer in Urban Design at Cardiff University
* The only textbook that provides practical design advice sourced from principles of residential layout design
* Comprehensive coverage of urban design theory gives an ideal introduction to the subject
* Encompasses sustainability, accessibility and holistic design – all the key concerns in designing the built environment

Download Link :
RS1
RS2
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Laser weapon design hits 100-kilowatt target

From the week gone by on the directed-energy weapons front: defense contractor Northrop Grumman reported that it got a solid-state laser to fire a beam with a potency of 105.5 kilowatts.

For the ray-gun wing of the military-industrial complex, the 100-kilowatt threshold is a major milestone, marking the entry point to weapons-grade laser weapons. Adding to the appeal is that solid-state lasers are much more compact, and less noxious, than chemical laser systems such as the one in the works for the 747-centric Airborne Laser.

The technical details of Northrop’s achievement break down this way, starting with a modular, “building block” approach that bodes well for scalable systems, the company said: For building blocks, the company utilizes “laser amplifier chains,” each producing approximately 15kW of power in a high-quality beam. Seven laser chains were combined to produce a single beam of 105.5 kW. The seven-chain JHPSSL laser demonstrator ran for more than five minutes, achieved electro-optical efficiency of 19.3 percent, reaching full power in less than 0.6 seconds, all with beam quality of better than 3.0.

Adding an eighth chain that the system was designed for would increase laser power to 120 kilowatts, Northrop says.

Where this test saw five minutes of continuous operation for the laser, altogether the system has been operated at above 100 kilowatts for a total duration of more than 85 minutes.

The efforts are part of the Pentagon’s Joint High Power Solid State Laser (JHPSSL) program.

Even though 100 kilowatts has long been the “proof of principle” sought for weapons systems, Northrop says that “in fact, many militarily useful effects can be achieved by laser weapons of 25 kW or 50 kW, provided this energy is transmitted with good beam quality, as our system does.”

Of course, this is still a laboratory laser system and not a field-tested, ruggedized product. “It is still a little heavy and a little big,” Dan Wildt, vice president of Northrop’s directed energy systems program, told the LA Times.

That’s probably a significant understatement. Says Noah Schactman at Wired’s Danger Room blog of the news from Northrop: Does that mean energy weapons are a done deal? Hardly. There are still all sorts of technical issues–thermal management and miniaturization, to name two–that have to be handled first. Then, the ray gunners have to find the money. The National Academies figure it’ll take another $100 million to get battlefield lasers right.

In a separate post, Schachtman reports on what’s involved in getting specific laser systems ready to go over the next several years.

Earlier this year, Boeing said that it had used a “kilowatt-class” solid-state laser to shoot down a UAV from a ground-based system. The company hopes that the Airborne Laser, meanwhile, will do its first-ever aerial target shoot sometime in 2009.

Sumber: CNet.com

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Why Use a Clamp Meter?

Mengapa mengukur Arus Listrik Menggunkan Tang Ampere?

Salah satu alat yang diperlukan pada saat kita melakukan commissioning dan pengujian arus listrik “test and run” mesin atau alat-alat yang menggunakan listrik lainnya dilapangan.

Clamp meters allow for measurement of current, without needing to disconnect the wires where the measurement occurs. By simply clamping the wire, you can get the measurement, and not cut the circuit. When using a multitester or a digital multimeter, the circuit has to be cut. In contrast, using a clamp meter, current can be measured by clamping a live wire over its sheath. In addition to its simple operation, it allows safe measurement of a higher current.

Clamp meters feature low internal resistance and have both a positive and negative lead. High current flow can indicate a short circuit, a defective component, or an unintentional ground. Low current flow can indicate high resistance, or poor current flow within the circuit. Both types of clamp meters (digital and analog) are designed to measure levels of direct current (DC) and alternating current (AC). Most products have built in sensors. Some clamp meters can test diodes or transistors while others can monitor thermocouples or resistance temperature detector (RTD) values. Some may adjust sampling rates automatically, display status information as a bar graph, and measure decibel (dB) readings. Our specialty clamp meters provide special measurement types and optional features. Some can test diodes or transistors. Others can monitor thermocouples or resistance temperature detector (RTD) values. Programmable clamp meters provide internal data storage and will allow you to establish activation triggers. Clamp meters are extremely useful and allow for many types of safe electrical testing.

Please visit Fluke Website for your information.

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Bagaimana Cara Menggunakan Multimeter

Using a Multimeter

A multimeter is used to make various electrical measurements, such as AC and DC voltage, AC and DC current, and resistance. It is called a multimeter because it combines the functions of a voltmeter, ammeter, and ohmmeter. Multimeters may also have other functions, such as diode and continuity tests. The descriptions and pictures that follow are specific to the Fluke 73 Series III Multimeter, but other multimeters are similar.

Important note: The most common mistake when using a multimeter is not switching the test leads when switching between current sensing and any other type of sensing (voltage, resistance). It is critical that the test leads be in the proper jacks for the measurement you are making.

Safety Information

• Be sure the test leads and rotary switch are in the correct position for the desired measurement.
• Never use the meter if the meter or the test leads look damaged.
• Never measure resistance in a circuit when power is applied.
• Never touch the probes to a voltage source when a test lead is plugged into the 10 A or 300 mA input jack.
• To avoid damage or injury, never use the meter on circuits that exceed 4800 watts.
• Never apply more than the rated voltage between any input jack and earth ground (600 V for the Fluke 73).
• Be careful when working with voltages above 60 V DC or 30 V AC rms. Such voltages pose a shock hazard.
• Keep your fingers behind the finger guards on the test probes when making measurements.
• To avoid false readings, which could lead to possible electric shock or personal injury, replace the battery as soon as the battery indicator appears.

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Input Jacks

The black lead is always plugged into the common terminal. The red lead is plugged into the 10 A jack when measuring currents greater than 300 mA, the 300 mA jack when measuring currents less than 300 mA, and the remaining jack (V-ohms-diode) for all other measurements.

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Range

The meter defaults to autorange when first turned on. You can choose a manual range in V AC, V DC, A AC, and A DC by pressing the button in the middle of the rotary dial. To return to autorange, press the button for one second.

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Automatic Touch Hold Mode

The Touch Hold mode automatically captures and displays stable readings. Press the button in the center of the dial for 2 seconds while turning the meter on. When the meter captures a new input, it beeps and a new reading is displayed. To manually force a new measurement to be held, press the center button. To exit the Touch Hold mode, turn the meter off.

Note: stray voltages can produce a new reading.

Warning: To avoid electric shock, do not use the Touch Hold to determine if a circuit with high voltage is dead. The Touch Hold mode will not capture unstable or noisy readings.

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AC and DC Voltage

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Resistance

Turn off the power and discharge all capacitors. An external voltage across a component will give invalid resistance readings.

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Diode Test

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Continuity Test

This mode is used to check if two points are electrically connected. It is often used to verify connectors. If continuity exists (resistance less than 210 ohms), the beeper sounds continuously. The meter beeps twice if it is in the Touch Hold mode.

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Current

Warning: To avoid injury, do not attempt a current measurement if the open circuit voltage is above the rated voltage of the meter.

To avoid blowing an input fuse, use the 10 A jack until you are sure that the current is less than 300 mA.

Turn off power to the circuit. Break the circuit. (For circuits of more than 10 amps, use a current clamp.) Put the meter in series with the circuit as shown and turn power on.

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The Future of Air Traffic Control: Human Operators and Automation

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Hunting: Buku SolidWorks 2007 Bible

“The most complete resource for SolidWorks on the market. Matt Lombard’s in-depth knowledge plus his snappy wit and wisdom make SolidWorks accessible to users at all levels.”
– Mike Sabocheck, Territory Technical Manager, SolidWorks Corporation
The most comprehensive single reference on SolidWorks
Whether you’re a new, intermediate, or professional user, you’ll find the in-depth coverage you need to succeed with SolidWorks 2007 in this comprehensive reference. From customizing the interface to exploring best practices to reinforcing your knowledge with step-by-step tutorials, the techniques and shortcuts in this detailed book will help you accomplish tasks, avoid the time-consuming pitfalls of parametric design, and get a firm handle on one of the leading 3D CAD programs on the market.
* Customize the user interface and connect hotkeys to macros
*Create sketches, parts, assemblies, and drawings
*Build intelligence into parts
*Work with patterns, equations, and configurations
*Learn multibody, surface, and master model techniques
*Write, record, and edit Visual Basic(r) macros
Design with advanced 3D features
Download:

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Standard Gaji Di Indonesia

Ada file menarik dari www.kellyservices.co.id, Sudah layakkah gaji yang anda terima saat ini? Sebaiknya compare aja dengan data yang didapat dari kelly search ini.

Siapakah Kelly Services?  Silahkan cek di http://kellyservices.co.id

Penasaran ingin mengetahui standard gaji yang ada di Indonesia di 2008? Silahkan Klik Disini Download!

Cara Membuka Blok Yang Diprotek Di Siemens Simatic Step 7

Baru-baru ini, saya menerima telpon dari seorang teman. Dia mempunyai masalah di mesin packaging buatan Jerman. Kebetulan menggunakan PLC Siemen S7-300. Pada saat dia membuka program PLC Siemens Simatic S7, ada beberapa block penting yang diprotek. Karena tidak mungkin menunggu berhari-hari untuk menyelesaikan problem dimesin tersebut. Sementara seandainya memanggil orang bikin program dari Jerman. Woow.. lost time lost money. Simak tulisan saya dibawah in.

Bagaimana saya membuka blok yang diprotek?

Hal pertama yang saya akan dilakukan adalah mencari tentang software ini di Google dan membaca tentang software ini semuanya. Setelah itu mencoba eksplorasi perangkat lunak ini. Seseorang (mungkin S7 programmer) menjelaskan tentang ‘Generate Source’ dan saya ditunjukkan olehnya sebuah contoh yang tepat. Lebih lanjut dia tunjukan pada saya bagaimana cara kunci blok melalui KNOW_HOW_PROTECT. It was amazing, mereka hanya menulis baris ini (KNOW_HOW_PROTECT) di dalam sebuah program dan cara mengkompilasi kode. Dikompilasi kode yang dikenal sebagai blok. Blok yang telah dilindungi yang berarti kode di dalam blok tidak dapat terlihat oleh orang lain. Kemudian menghapus sumber dan blok sekarang yang diprotek. Bingung deh…

Setelah saya coba, berhasil. Berikut ini langkah-langkah yang harus dilakukan untuk membuka proteksi blok programnya:

Step 1 : Download program *.dbf editor. Editor dbf yang saya gunakan. Untuk download silahkan klik berikut ini http://www.ks-soft.net/download/other/dbf_edit.zip atau dari Mr. PLC di http://forums.mrplc.com/index.php?s=e6d59e5a3589ec647fce45abc6acab04&act=Attach&type=post&id=895

Step 2: Setelah anda download file tsb. Extract file dbf_edit.exe dikomputer anda didrive mana saja dan buat folder DBFEDIT. Contohnya saja saya extract di C:\DBFEDIT\DBF_EDIT.exe.

Step 3: Untuk membuka proteksi blok tersebut (unlock), copy file SUBBLK.DBF dari folder ..\PROJECT\ombstx\offline\00000001\ dimana projek tersebut anda simpan.Kemudian paste di dalam folder C:\DBFEDIT\ (yang sebelumnya dibuat di Langkah 2).

Step 4:Kemudian jalankan Command Prompt(Dos Windows) dengan cara mengklik START -> Run -> Ketik Cmd -> Kemudian Enter atau di Start -> All Programs -> Accessories -> Command Prompt

Step 5: Ikuti perintah berikutnya,

C:\>cd dbfedit
C:\DBFEDIT>dbf_edit.exe subblk.dbf

Sebuah aplikasi DOS akan membukan, cari kolom PASSWORD dengan menekan arah panah ke kanan pada keyboard. Dan ganti angka 3 menjadi 0 dengan menekan tombol ENTER dan masukan nilai 0 untuk membuka proteksi blok tersebut (unlock the block). Kemudian tekan Esc atau F10 untuk SAVE dan Exit. Lihat di print screen di bawah ini.

Step 6: Copy the SUBBLK.DBF yang tadi ada di dalam folder C:\DBFEDIT\ dan paste dimana file tersebut berada sebelumnya. Ingat lakukan backup file original SUBBLK.DBF.

Step 7: Sekarang buka file project di SIMATEC Step 7 software. Semua blok yang terproteksi kini sudah terbuka (All the blocks are unlocked).

Jadi sekarang berhasil. Lihat print screen sebelumnya (Lock) dan sesudahnya (Unlock).

Untuk pertama kali saya memerlukan waktu kurang lebih 1 jam, tapi kalau sudah terbiasa 5 menit saja cukup.

SELAMAT MENCOBA

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