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Delhi Rolls Out a Massive Network of Surveillance Cameras

The state government says closed-circuit TVs will help fight crime, but digital liberties activists are concerned about the project's lack of transparency

3 min read
Image of Dehli surrounded by electrical wires.
Photo: iStock

In India, the government of Delhi is rolling out an ambitious video surveillance program as a crime-prevention measure. Technicians will install more than a quarter million closed-circuit TV (CCTV) cameras near residential and commercial properties across the city, and in schools. A central monitoring system is expected to take care of behind-the-scenes logistics, though authorities have not shared details on how the feeds will be monitored.

After delays due to political and legal wrangles, the installations began on 7 and 8 July. The first cameras to go up in a residential area were installed in Laxmi Bai Nagar, at a housing society for government employees, and at the upmarket Pandara Road in New Delhi. When the roll out is complete, there will be an average of 4,000 cameras in each of Delhi’s 70 assembly constituencies, for a total of around 280,000 cameras.

In early 2020, the National Capital Territory of Delhi (usually just called ‘Delhi’), which includes New Delhi, the capital of India, will vote to elect a new state assembly. Lowering the crime rates is a key election issue for the incumbent Aam Aadmi Party (literally, Common Man’s [sic] Party). The party has promised that the CCTV cameras will deter premeditated crime and foster a semblance of order among the general public.

However, digital rights activists have raised a number of red flags. “None of the [operational] details [about the project] have been shared by the Delhi government,” says Apar Gupta, executive director of the Internet Freedom Foundation (IFF), an independent digital liberties organization. “There [are] no legal or regulatory mechanisms in place.”

In June, the IFF served a legal notice to the Delhi government to halt the CCTV camera installations, stating that the project put the privacy and freedom of Delhi residents at risk. Kritika Bhardwaj, a Supreme Court lawyer who advised the IFF, says “We have learnt that recordings will be accessible to ‘residents’ welfare associations, police, and the government,’ with absolutely no clarity on who will maintain these CCTV systems, how long the footage will be stored, and whether there are any security requirements for storing/accessing such footage.”

Image of the CCTV's control room in Dehli. Operators in a control room monitor CCTVs installed on 6 July in the classrooms of a public school in Lajpat Nagar, a neighborhood of New Delhi. More than 1,000 schools in Delhi will be equipped with CCTV cameras by November.Photo: Getty Images

Bhardwaj calls this “a matter of grave concern” for a program that will cost the equivalent of US $73 million and affect the lives of more than 16 million people. There have been no public consultations inviting comments or suggestions on the rules governing the cameras, no cost-benefit analyses, and the tender process was done without the bid documents and the scope of work being made publicly accessible, the IFF reports.

Bhardwaj also points out, “There is no statutory framework governing the project.” This is a marked departure from the way public surveillance camera systems work in other cities, such as in London, where they are governed by data protection laws and strict guidelines. Images recorded by London’s cameras are automatically deleted after 31 days. No such stipulation exists for Delhi’s project. Government authorities in Delhi did not respond to a request for comment.

Studies also show that the efficacy of CCTV cameras in crime prevention may be overestimated. “They haven’t been proven to reduce violent crime,” says Gabe Turner of Security Baron, a consumer-oriented security website, though there is some evidence that cameras can discourage petty crimes if used as part of a broader security system, which includes security guards or improved lighting. They can also make the public feel safer. For Delhi residents, this could mean trading their privacy for the perception of safety.

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The Inner Beauty of Basic Electronics

Open Circuits showcases the surprising complexity of passive components

5 min read
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A photo of a high-stability film resistor with the letters "MIS" in yellow.
All photos by Eric Schlaepfer & Windell H. Oskay
Blue

Eric Schlaepfer was trying to fix a broken piece of test equipment when he came across the cause of the problem—a troubled tantalum capacitor. The component had somehow shorted out, and he wanted to know why. So he polished it down for a look inside. He never found the source of the short, but he and his collaborator, Windell H. Oskay, discovered something even better: a breathtaking hidden world inside electronics. What followed were hours and hours of polishing, cleaning, and photography that resulted in Open Circuits: The Inner Beauty of Electronic Components (No Starch Press, 2022), an excerpt of which follows. As the authors write, everything about these components is deliberately designed to meet specific technical needs, but that design leads to “accidental beauty: the emergent aesthetics of things you were never expected to see.”

From a book that spans the wide world of electronics, what we at IEEE Spectrum found surprisingly compelling were the insides of things we don’t spend much time thinking about, passive components. Transistors, LEDs, and other semiconductors may be where the action is, but the simple physics of resistors, capacitors, and inductors have their own sort of splendor.

High-Stability Film Resistor

A photo of a high-stability film resistor with the letters "MIS" in yellow.

All photos by Eric Schlaepfer & Windell H. Oskay

This high-stability film resistor, about 4 millimeters in diameter, is made in much the same way as its inexpensive carbon-film cousin, but with exacting precision. A ceramic rod is coated with a fine layer of resistive film (thin metal, metal oxide, or carbon) and then a perfectly uniform helical groove is machined into the film.

Instead of coating the resistor with an epoxy, it’s hermetically sealed in a lustrous little glass envelope. This makes the resistor more robust, ideal for specialized cases such as precision reference instrumentation, where long-term stability of the resistor is critical. The glass envelope provides better isolation against moisture and other environmental changes than standard coatings like epoxy.

15-Turn Trimmer Potentiometer

A photo of a blue chip
A photo of a blue chip on a circuit board.

It takes 15 rotations of an adjustment screw to move a 15-turn trimmer potentiometer from one end of its resistive range to the other. Circuits that need to be adjusted with fine resolution control use this type of trimmer pot instead of the single-turn variety.

The resistive element in this trimmer is a strip of cermet—a composite of ceramic and metal—silk-screened on a white ceramic substrate. Screen-printed metal links each end of the strip to the connecting wires. It’s a flattened, linear version of the horseshoe-shaped resistive element in single-turn trimmers.

Turning the adjustment screw moves a plastic slider along a track. The wiper is a spring finger, a spring-loaded metal contact, attached to the slider. It makes contact between a metal strip and the selected point on the strip of resistive film.

Ceramic Disc Capacitor

A cutaway of a Ceramic Disc Capacitor
A photo of a Ceramic Disc Capacitor

Capacitors are fundamental electronic components that store energy in the form of static electricity. They’re used in countless ways, including for bulk energy storage, to smooth out electronic signals, and as computer memory cells. The simplest capacitor consists of two parallel metal plates with a gap between them, but capacitors can take many forms so long as there are two conductive surfaces, called electrodes, separated by an insulator.

A ceramic disc capacitor is a low-cost capacitor that is frequently found in appliances and toys. Its insulator is a ceramic disc, and its two parallel plates are extremely thin metal coatings that are evaporated or sputtered onto the disc’s outer surfaces. Connecting wires are attached using solder, and the whole assembly is dipped into a porous coating material that dries hard and protects the capacitor from damage.

Film Capacitor

An image of a cut away of a capacitor
A photo of a green capacitor.

Film capacitors are frequently found in high-quality audio equipment, such as headphone amplifiers, record players, graphic equalizers, and radio tuners. Their key feature is that the dielectric material is a plastic film, such as polyester or polypropylene.

The metal electrodes of this film capacitor are vacuum-deposited on the surfaces of long strips of plastic film. After the leads are attached, the films are rolled up and dipped into an epoxy that binds the assembly together. Then the completed assembly is dipped in a tough outer coating and marked with its value.

Other types of film capacitors are made by stacking flat layers of metallized plastic film, rather than rolling up layers of film.

Dipped Tantalum Capacitor

A photo of a cutaway of a Dipped Tantalum Capacitor

At the core of this capacitor is a porous pellet of tantalum metal. The pellet is made from tantalum powder and sintered, or compressed at a high temperature, into a dense, spongelike solid.

Just like a kitchen sponge, the resulting pellet has a high surface area per unit volume. The pellet is then anodized, creating an insulating oxide layer with an equally high surface area. This process packs a lot of capacitance into a compact device, using spongelike geometry rather than the stacked or rolled layers that most other capacitors use.

The device’s positive terminal, or anode, is connected directly to the tantalum metal. The negative terminal, or cathode, is formed by a thin layer of conductive manganese dioxide coating the pellet.

Axial Inductor

An image of a cutaway of a Axial Inductor
A photo of a collection of cut wires

Inductors are fundamental electronic components that store energy in the form of a magnetic field. They’re used, for example, in some types of power supplies to convert between voltages by alternately storing and releasing energy. This energy-efficient design helps maximize the battery life of cellphones and other portable electronics.

Inductors typically consist of a coil of insulated wire wrapped around a core of magnetic material like iron or ferrite, a ceramic filled with iron oxide. Current flowing around the core produces a magnetic field that acts as a sort of flywheel for current, smoothing out changes in the current as it flows through the inductor.

This axial inductor has a number of turns of varnished copper wire wrapped around a ferrite form and soldered to copper leads on its two ends. It has several layers of protection: a clear varnish over the windings, a light-green coating around the solder joints, and a striking green outer coating to protect the whole component and provide a surface for the colorful stripes that indicate its inductance value.

Power Supply Transformer

A photo of a collection of cut wires
A photo of a yellow element on a circuit board.

This transformer has multiple sets of windings and is used in a power supply to create multiple output AC voltages from a single AC input such as a wall outlet.

The small wires nearer the center are “high impedance” turns of magnet wire. These windings carry a higher voltage but a lower current. They’re protected by several layers of tape, a copper-foil electrostatic shield, and more tape.

The outer “low impedance” windings are made with thicker insulated wire and fewer turns. They handle a lower voltage but a higher current.

All of the windings are wrapped around a black plastic bobbin. Two pieces of ferrite ceramic are bonded together to form the magnetic core at the heart of the transformer.

This article appears in the February 2023 print issue.

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