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A magnet is an object that has a magnetic field. It can be in the form of a permanent magnet or an electromagnet.
Wire made from a special alloy which changes its molecular structure at a certain temperature causing it to shrink. This effect can usefully be applied to point and signal actuation. Some types require a tension spring to pull it back to its original length while others will return unaided, although a spring is still required to keep the wire tight, it can only pull when shrinking, it cannot push.
See also TBs: G19/01, G19/02, G22/01, G23/01 & G23/02.
A microprocessor (sometimes abbreviated µP) is a programmable digital electronic component that incorporates the functions of a central processing unit (CPU) on a single semiconducting integrated circuit (IC).
A DCC decoder intended for fitting in a loco.
Is the process of superimposing information onto a pure sine wave (Carrier wave), this process can be achieved by any of fourmethods, amplitude (AM), frequency (FM), Phase (PM) or Pulse (PAM, PWM, or PPM)
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An electronic circuit that has a single (mono) stable state and an unstable state, an input will cause the circuit to assume the unstable state, when the input signal is removed and after a predictable delay the circuit will return to the stable state. This behaviour is the basis of most timer circuits.
metal-oxide-semiconductor field-effect transistor MOSFET
A communications device that multiplexes (combines) several signals for transmission over a single medium. A demultiplexor completes the process by separating multiplexed signals from a transmission line. Frequently a multiplexor and demultiplexor are combined into a single device capable of processing both outgoing and incoming signals.
A multiplexor is sometimes called a mux and also spelled as multiplexer.