TV aerial plug
TV aerial plug
|Type||RF coaxial connector|
|Designer||at Belling & Lee Ltd in Enfield, United Kingdom|
|Designed||Around 1922 (Belling-Lee)|
Antenna sockets are female antenna connectors that have slots or holes which accept the pins or blades of antenna plugs inserted into them and deliver or receive TV signal to or from the plugs. Sockets are generally mounted on the TV set or in the wall. Sockets are usually designed to reject any plug which is not built to the same standard. Some sockets have one or more pins that connect to holes in the plug.
The Belling-Lee connector or IEC 169-2 connector, more often simply known as TV aerial plug or PAL connector, is the traditional antenna connector for European TV sets and FM / DAB-radio receivers. It is the oldest coaxial RF connector still commonly used in consumer devices today. It connects a receiver to a terrestrial VHF/UHF roof antenna, antenna amplifier, or CATV network, via a coaxial cable.
It was invented at Belling & Lee Ltd in Enfield, United Kingdom, around 1922, at the time of the first BBC broadcasts. It was originally only intended for medium frequency broadcasts, where accurate impedance matching of an antenna connector is not a concern.
Belling-Lee vs other connectors
Unlike the coaxial F connector used today for the same purpose in North America, the IEC 61169-2 connector is not matched to the 75-ohm characteristic impedance of the antenna cable used, having an impedance closer to 50 ohms. This lack of impedance matching causes signal reflections in the cable, leading to noticeable signal distortion on VHF and UHF frequencies (but not MW or Shortwave).
- The IEC-169-2 connector is recognised as a source of signal distortion and has become a particular concern with digital signal reception, specifically UHF HDTV.
- DAB (digital radio) and other reception modes are not as severely affected by the impedance matching issue, so only HDTV and satellite reception systems are encouraged to use the F connector.
- In spite of being somewhat unsuitable for modern analogue VHF and UHF TV frequencies, due to industrial inertia, the Belling Lee connector is still used today as a TV signal reception connector.
- In Europe and the Americas this connector is not used to connect satellite TV antennas. The more electrically suitable 75-ohm F connector is standard. However, the obsolete BSB receiver used a Belling Lee connector for the LNB feed  as did the Nokia SAT1700 analogue Sky receiver.
Miniature Belling Lee
There is also a miniature Belling Lee connector which was used for internal connections inside some equipment (including BBC RC5/3 Band II receiver and the STC AF101 Radio Telephone). The standard Belling Lee plug is about 33 mm long and 9.5 mm diameter (mating surface); the miniature version looks similar but is only about 17 mm long and 4.4 mm diameter. Amalgamated Wireless Australasia (AWA) used miniature Belling & Lee connectors, internally, in their 25M series Land Mobile two-way radios in the early 1970s. The socket is a Belling & Lee L1465/CS whilst the plug is a Belling & Lee 1465/PF.
See also↑Jump back a section
- "Whom.co.uk". Whom. Retrieved 2011-01-12.
- "G3NPF and M1AIM Home Page Technical Section (Connectors)". Homepages.tesco.net. Retrieved 2011-01-12.