Gakken EX-System
Encyclopedia
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
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...
kits produced by Gakken
Gakken
is a Japanese publishing company founded in 1947 by Hideto Furuoka, which also produces educational toys. Their annual sales is reported at ¥ 821 billion ....
in the late 1970s. The kits use denshi block
Denshi block
A denshi block is a small plastic box containing an electronic component. The blocks are used in some educational electronics kits, such as the Gakken EX-150, to allow experiments to be performed easily and safely.-Description:...
s (also known as electronic blocks) to allow electronics 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. Over 25 years after its original release, one of the main kits from the series was reissued in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
in 2002.
History
A brief timeline:1972: Gakken and Denshi Block Mfg. Co. Ltd. collaborate to release denshi block kits under Gakken's name.
1976: The EX series was released.
1981: The successor to the EX series, the FX series, is released.
1986: Gakken stops producing denshi block kits.
2002: The EX-150 is reissued in Japan, and is successful enough to justify the production of an expansion kit.
EX-System kits
- a selection of denshi blocks,
- the main unit in which circuitsElectrical networkAn 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...
are built, - some additional external apparatus, and
- an instruction booklet.
Denshi blocks
A denshi block (or electronic block) is a small plasticPlastic
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 component. Each block has 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 on its sides, and 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. The top of each block is labelled with 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 component it contains.
A circuit is built by placing a configuration of denshi blocks in a two dimension
Dimension
In physics and mathematics, the dimension of a space or object is informally defined as the minimum number of coordinates needed to specify any point within it. Thus a line has a dimension of one because only one coordinate is needed to specify a point on it...
al grid. Because of the two dimensional layout and the labels on the blocks, a configuration of blocks resembles a schematic of the circuit.
While most denshi blocks are of a standard size, there are some larger blocks for containing complex components. In particular, the synthesiser block and the FM
FM broadcasting
FM broadcasting is a broadcasting technology pioneered by Edwin Howard Armstrong which uses frequency modulation to provide high-fidelity sound over broadcast radio. The term "FM band" describes the "frequency band in which FM is used for broadcasting"...
tuner
Tuner (radio)
A radio tuner is a subsystem that receives radio broadcasts and converts them into audio-frequency signals which can be fed into an amplifier driving a loudspeaker. FM tuner, AM tuner, Digital Audio Broadcasting DAB tuner, etc. are types of radio tuner dealing with transmissions using different...
block are much larger, occupying an area 4x5 standard blocks and 3x6 standard blocks, respectively.
The main unit
The main unit holds the grid of blocks (it has room for 6×8 standard blocks), batteriesBattery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
and some additional circuitry. When fully expanded, the main unit contains:
- an antennaAntenna (radio)An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
circuit, with tuning knob - an amplifierAmplifierGenerally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...
, with volume control - a light sensitive resistorResistorA 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...
(CdS cell / CadmiumCadmiumCadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
cell) - an analogue meter
External apparatus
Some circuits require apparatus which are unsuitable for putting inside blocks, for example, a crystal earpieceHeadphones
Headphones are a pair of small loudspeakers, or less commonly a single speaker, held close to a user's ears and connected to a signal source such as an audio amplifier, radio, CD player or portable Media Player. They are also known as stereophones, headsets or, colloquially, cans. The in-ear...
. These have wires which terminate in flat metal contacts, and they are connected to the circuit by sliding the contacts between the metal strips of two neighbouring blocks.
Some experiments also involve non-electrical apparatus, for example, the optical fibres from the optical
Optics
Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light...
experiments kit. The optical fibres are connected via a special block.
Instruction booklet
The instruction booklet gives the correct arrangement of blocks to make each circuit, a full schematic for it and a brief explanation of how the experiment works.The original EX-System kits
The names of the original kits, EX-15, EX-30, etc., give the number of experiments that could be performed with them. By purchasing expansion kits, EX-A, EX-B, etc., any of the kits could be upgraded to support the complete set of 191 experiments. Each expansion kit added new denshi blocks and came with a piece of external apparatus or some circuitry to be installed in the main unit.Note that the EX-FM kit is compatible with all of the main kits, although some of its experiments require blocks from later kits in the series.
| Name | As upgrade | Significant components | Example experiment |
|---|---|---|---|
| EX-15 | antenna, crystal earpiece | Diode Detector Radio | |
| EX-30 | EX-15 + EX-A | morse key block, short cables | Morse Code Morse code Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment... Practice Circuit |
| EX-60 | EX-30 + EX-B | IC Amplifier | I-Diode Detector + IC Integrated circuit An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material... Radio (Fixed Bias) |
| EX-100 | EX-60 + EX-C | tester probes | Wireless Water Level Warning Device |
| EX-120 | EX 100 + EX-D | microphone, CdS cell | Circuit which Buzzes when Struck by Light |
| EX-150 | EX-120 + EX-E | analogue meter | Noise Level Meter |
| EX-181 | EX-150 + EX-System Synthesiser | synthesiser block, resistance board | Sound of Car being Reversed |
| EX-FM | any main kit + EX-FM | FM tuner block | FM Receiver Receiver (radio) A radio receiver converts signals from a radio antenna to a usable form. It uses electronic filters to separate a wanted radio frequency signal from all other signals, the electronic amplifier increases the level suitable for further processing, and finally recovers the desired information through... with Microphone Microphone A microphone is an acoustic-to-electric transducer or sensor that converts sound into an electrical signal. In 1877, Emile Berliner invented the first microphone used as a telephone voice transmitter... Mixer Mixing console In professional audio, a mixing console, or audio mixer, also called a sound board, mixing desk, or mixer is an electronic device for combining , routing, and changing the level, timbre and/or dynamics of audio signals. A mixer can mix analog or digital signals, depending on the type of mixer... |
The reissue kits
The reissued EX-150 kit from 2002 is almost identical to the original EX-150 from the 1970s. Due to differences in the availability of certain components, there are changes in some of the circuitry. A consequence is that some of the experiments have been altered.Optical expansion kit
The reissued EX-150 sold well enough to justify an expansion kit. It is designed for the reissued EX-150 only and, allegedly, will not work with the original. The expansion contains components for performing optical experiments, including LEDLEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....
blocks, optical fibres and a 555 timer IC
555 timer IC
The 555 timer IC is an integrated circuit used in a variety of timer, pulse generation and oscillator applications. The part is still in widespread use, thanks to its ease of use, low price and good stability. , it was estimated that 1 billion units are manufactured every year.- Design :The IC...
block. As some of the experiments involve two separate circuits, a plastic tray with room for 6 x 5 standard blocks is also provided.
An example experiment:
- The kit includes a disk with bands of black and white regions printed on it. The user builds a circuit in the tray which spins the disk. In the main unit, the user builds a circuit which can "read" the regions via the optic fibre and produce a soundSoundSound 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...
. By moving the end of the optical fibre across the spinning disk, the user can play notes of the musical scaleMusical scaleIn music, a scale is a sequence of musical notes in ascending and descending order. Most commonly, especially in the context of the common practice period, the notes of a scale will belong to a single key, thus providing material for or being used to conveniently represent part or all of a musical...
.
Trivia
Texas Instruments
Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...
SN76477
Texas Instruments SN76477
SN76477 "complex sound generator" was a sound chip produced by Texas Instruments . The chip came to market in 1978, and TI production of the part ceased some time ago. More recently, a 100% compatible version, identified as ICS76477, has been listed as 'in stock' by at least one US-based component...
sound chip
Sound chip
A sound chip is an integrated circuit designed to produce sound . It might be doing this through digital, analog or mixed-mode electronics...
. Since the chip requires a separate 9V
Volt
The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
power supply, the synthesiser block had a compartment for holding a 9V battery.
Although the EX-FM tuner block supported 10 new experiments in Japan, in
the English language
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
version available in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, only 4 experiments are described.
A Japanese man, Hiroyuki Inoue, built an IPv6
IPv6
Internet Protocol version 6 is a version of the Internet Protocol . It is designed to succeed the Internet Protocol version 4...
communication module as a block for the EX-150.
The Denshi Block system was also sold under the Skilcraft and Tron Link brands.