A denshi block is a small plastic

Plastic

A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...

 box containing an electronic

Electronics

Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

 component. The blocks are used in some education

Education

Education in its broadest, general sense is the means through which the aims and habits of a group of people lives on from one generation to the next. Generally, it occurs through any experience that has a formative effect on the way one thinks, feels, or acts...

al electronics kits, such as the Gakken EX-150

Gakken EX-System

The Gakken EX-System is a series of educational electronics kits produced by Gakken in the late 1970s. The kits use denshi blocks to allow electronics experiments to be performed easily and safely...

, to allow experiment

Experiment

An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...

s to be performed easily and safely.

Description

The size and shape of denshi blocks depend on the kit they are from. The blocks of a particular kit will have the same height, usually a few centimetres, and cover a rectangular area a few centimetres on either side. They are designed to fit into a grid of squares, so blocks always occupy some rectangular area of these squares, with the majority of blocks occupying just one square.

Most blocks contain either a single electronic component, for example a resistor

Resistor

A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's...

, or just some wiring

Wire

A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads and to carry electricity and telecommunications signals. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Standard sizes are determined by various...

. Some unusual blocks contain complex circuitry

Electrical network

An electrical network is an interconnection of electrical elements such as resistors, inductors, capacitors, transmission lines, voltage sources, current sources and switches. An electrical circuit is a special type of network, one that has a closed loop giving a return path for the current...

, for example, a sound

Sound

Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...

 synthesiser in the Gakken EX-System

Gakken EX-System

The Gakken EX-System is a series of educational electronics kits produced by Gakken in the late 1970s. The kits use denshi blocks to allow electronics experiments to be performed easily and safely...

 or a microcomputer

Microcomputer

A microcomputer is a computer with a microprocessor as its central processing unit. They are physically small compared to mainframe and minicomputers...

 in the Gakken FX-System. Usually, a schematic

Schematic

A schematic diagram represents the elements of a system using abstract, graphic symbols rather than realistic pictures. A schematic usually omits all details that are not relevant to the information the schematic is intended to convey, and may add unrealistic elements that aid comprehension...

 representation of the block's contents is printed on its top.

On the sides of each block are conductive metal

Metal

A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...

 strips, so that when two blocks are placed side-by-side, their metal strips touch allowing electricity

Electricity

Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...

to flow between them.

A circuit is built by placing a configuration of denshi blocks in a two dimensional grid. The instructions for building the circuit need only illustrate where to place the blocks in the grid. Because of the two dimensional layout and the labels on the blocks, a configuration of blocks resembles a schematic of the circuit.

External links and references

• Denshi Blocks Mfg. Co. Ltd. Home Page (in Japanese)
• Gakken's EX-150 Page (in Japanese)
• Dostál, J. Electronic kits in education. Olomouc, EU: Votobia, 2008. 74 s. ISBN 978-80-7220-308-6.