N - November - dah-dit
n.
Shorthand notation for divide by 1,000,000,000 or nano.
N connector.
(in full, Type N connector) is a threaded RF connector used to join coaxial cables. It was one of the first connectors capable of carrying microwave-frequency signals, and was invented in the 1940s by Paul Neill of Bell Labs, for whom the connector is named.
See also: Fitting an 'N' connector plug.
nano.
The metric prefix for 10-9, or divide by 1,000,000,000.
Narrow Band FM / NFM/ NBFM.
Used for voice communications in commercial and amateur radio settings. In two-way radio, narrowband narrow-fm (N-FM) is used to conserve bandwidth allowing more users to use the available space.
NATO Phonetic Alphabet.
NB.
NBFM.
Near Field (of an antenna).
The region of the electromagnetic field immediately surrounding an antenna where the reactive field dominates and where the field strength as a function of angle (antenna pattern) depends upon the distance from the antenna. It is a region in which the electric and magnetic fields do not have a substantial plane-wave character, but vary considerably from point-to-point.
Near Vertical Incidence Sky-wave (NVIS).
The propagation mode that uses the ionosphere as parabolic reflector to increase local communications on HF to 200 - 300 miles.
Negative Feedback.
The process in which a portion of the amplifier output is returned to the input, 180 degrees out of phase with the input signal.
Negative Offset.
The repeater input frequency is lower than the output frequency.
Net.
1. A group of amateurs who meet at regular times on a specific frequency to share common interests.
.
2. An on-air organised group during emergency communications.
Net Gain.
The overall gain of a transmission circuit.
Network.
1. A term used to describe several packet stations linked together to transmit data over long distances.
.
2. A term used to describe 2 or more computers linked together.
Neutralization.
Feeding part of the output signal from an amplifier back to the input so it arrives out of phase with the input. This negative feedback neutralizes the effect of positive feedback caused by coupling between the input and output circuits in the amplifier.
NFM.
NiCd or NiCad.
Nickel Cadmium (NiCd / NiCad).
A popular type of rechargeable battery for portable electronics and toys using the metals nickel (Ni) and cadmium (Cd) as the active chemicals. The abbreviation 'NiCad' is a registered trademark of the SAFT corporation and should not be used to refer generically to nickel-cadmium batteries. NiCd cells have a nominal cell potential of 1.2 V. This is lower than the 1.5 V of many popular primary cells, and consequently they are not appropriate as a replacement in all applications. However, unlike most primary cells, NiCds keep a near constant voltage throughout their service life. Some would consider the near constant voltage a drawback, as it makes it difficult to detect when the battery charge is low; this is usually a minor concern. Despite their lower nominal voltage, NiCds are better suited for high current applications. Due to a significantly lower internal resistance, they can supply high surge currents. This makes them a favourable choice for handheld transceivers. A disadvantage of NiCds is that certain usage patterns may cause a "false bottom" effect. Specifically, if the battery is consistently discharged to the same level, then fully recharged, the battery will eventually stop discharging on its own upon reaching this threshold.
See also: Rechargable Battery Information page.
Nickel Metal Hydride (NiMH).
A type of rechargeable battery similar to a nickel-cadmium (NiCd) battery but has a hydrogen-absorbing alloy for the anode instead of cadmium. Like in NiCd batteries, nickel is the cathode. A NiMH battery can have two to three times the capacity of an equivalent size NiCd and the memory effect is not as significant.
See also: Rechargable Battery Information page.
NiMH.
Noise Blanker (NB).
A function in a receiver or transceiver for reducing pulse-type interference noises on the received signal (e.g. ignition noise in a car).
Noise Bridge.
A test instrument used to determine the impedance of an antenna system.
Noise Reduction (NR).
A signsl filtering feature that reduces unwanted signal noise.
Nonionizing radiation.
Electromagnetic radiation that does not have sufficient energy to knock electrons free from their atoms. Radio frequency (RF) radiation is nonionizing.
Notch Filter.
A sharp and narrow rejection filter for elimination of interfering signals.
NPN transistor.
A
transistor that has a layer of P-type semiconductor material sandwiched between layers of N-type semiconductor material.
NR.
NVIS.