MCX connectors are coaxial

Coaxial

In geometry, coaxial means that two or more forms share a common axis; it is the three-dimensional linear analogue of concentric.Coaxial cable, as a common example, has a wire conductor in the centre a circumferential outer conductor and an insulating medium called the dielectric separating...

 RF connector

RF connector

A coaxial RF connector is an electrical connector designed to work at radio frequencies in the multi-megahertz range.RF connectors are typically used with coaxial cables and are designed to maintain the shielding that the coaxial design offers. Better models also minimize the change in transmission...

s developed in the 1980s. They have the same inner contact and insulator

Electrical insulation

thumb|250px|[[Coaxial Cable]] with dielectric insulator supporting a central coreThis article refers to electrical insulation. For insulation of heat, see Thermal insulation...

 dimensions as the SMB connector

SMB connector

SMB connectors are coaxial RF connectors developed in the 1960s. SMB connectors are smaller than SMA connectors.They feature a snap-on coupling and are available in either 50 Ω or 75 Ω impedance...

 but are 30% smaller. MCX is standardized in European CECC 22220.

They use a snap-on interface and usually have a 50 Ω impedance

Characteristic impedance

The characteristic impedance or surge impedance of a uniform transmission line, usually written Z_0, is the ratio of the amplitudes of a single pair of voltage and current waves propagating along the line in the absence of reflections. The SI unit of characteristic impedance is the ohm...

 (occasionally 75 Ω also) . They offer broadband capability from DC

Direct current

Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...

 to 6 GHz

GHZ

GHZ or GHz may refer to:# Gigahertz .# Greenberger-Horne-Zeilinger state — a quantum entanglement of three particles.# Galactic Habitable Zone — the region of a galaxy that is favorable to the formation of life....

. The contact surfaces are gold-plated.

This type of connector is used on the Apple Airport Extreme Base Station's external antenna port and requires an adapter for most antennas. MCX and the smaller MMCX connector

MMCX connector

MMCX connectors are coaxial RF connectors similar to MCX but smaller. They conform to the European CECC 22 000 specification....

 are frequently used to connect external antennas
to GPS receivers

GPS navigation device

A GPS navigation device is any device that receives Global Positioning System signals for the purpose of determining the device's current location on Earth...

. They are also common on USB DVB-T

DVB-T

DVB-T is an abbreviation for Digital Video Broadcasting — Terrestrial; it is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in the UK in 1998...

tuners for computers and laptops, to connect an external antenna to the tuner.

The outer diameter of the plug is approx 3.6 mm or 0.140 inch.