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Glossary H
Hall effect
This a transistor type that is affected by a magnetic field placed in close proximity
See MERG TBs A7/2/ 3/ 4 merg members only
Handset
Header plug or socket
Heat sink
Waste heat is produced in transistors due to the current flowing through them. Heat sinks are needed for power transistors because they pass large currents. If you find that a transistor is becoming too hot to touch it certainly needs a heat sink! The heat sink helps to dissipate (remove) the heat by transferring it to the surrounding air.
http://www.kpsec.freeuk.com/components/heatsink.htm
Hector
This is a track detector using an optical system to detect the location of train Merg kit for members
High
This what we call greater than the base voltage or ground e.g. so high is 5v ~ 4.4volts above 0
HYPOTRAC
This a high voltage track detector system for 2 rail Model railway track , see TB T9/2 merg members only
Hysteresis loop
Hysteresis is wellknown in ferromagnetic materials. When an external magnetic field is applied to a ferromagnet, the ferromagnet absorbs some of the external field. Even when the external field is removed, the magnet will retain some field: it has become magnetized.
Hysteresis
The term is also used to refer to one of the display modules often to be seen on the MERG exhibition stand. This is because the track layout on the module resembles the graph of a hysteresis loop.