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 Buzz words! or FUTS! - frequently used terms. 19/12/10 
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Post Buzz words! or FUTS! - frequently used terms. 19/12/10
This list will be added to as ideas, or requests, come forward.

Burn = A meteorite burning up and producing a trail of ionised particles.

Cross polarisation loss = The loss resulting from the antennas at each end of a path being of different polarisation.
Between a vertical transmit antenna and a horizontal receive antenna , theoretically, there would be infinite loss - no energy transfered.
In reality, due to other things having an effect, the loss is regarded as being 20 - 26dB.
To ensure the best possible chance of getting the maximum out of theVHF/UHF bands you will find horizontal polarisation is a must.
Preferably using a directional antenna with reasonable gain although something as simple as a halo, big wheel or rotatable dipole will be a huge improvement over anything vertically polarised.

A First = Refers to a first contact made on a band between two DXCCs
As technology improves, and new bands are released in various countries there are chances of "Firsts".
Particularly bands like 4M and the higher bands.

Geminids = Meteor shower in December and usually peak around the 13th - 14th.

Hardline = A form of coaxial cable with a solid copper outer, usually corrugated, foam filled and an inner core of either solid copper, copper tube, or some other material eg. aluminium, with a copper outer surface.
Low loss and in general use at higher frequencies.
The cable is rigid so a more flexible tail is required around the rotator.
Sizes from 1/4" to 1 5/8".
Even larger cables, often with a spacer rather than foam filled.

Hepburn = William Hepburn's website http://dxinfocentre.com/tropo_nwe.htmlwhich gives
predictive tropo maps.
You can select the area you wish to look at.

HSCW = High speed CW. Today this will be computer generated but, before the advent of computer, modified tape recorders would be used to sped up, and slow down the Morse.

KST = Refers to http://www.on4kst.com - A combination of cluster/chat room/QSO mapping used to keep track of what is happening on the bands.
The screen can be configured to your own requirements.
Also used to arrange MS (meteor scatter) contacts where random operation is problematical.
4M being a good example as frequency allocations vary considerably country to country.

LiveMUF - http://g7rau.demon.co.uk/default.aspx?menu=5000 is a mapping tool developed by G7RAU.
Working in collaboration with true VHF propagation experts he has created a software package that utilises data from the DX cluster to predict potential QSO paths.
A huge benefit of this software is its database capability allowing post opening analysis of data.
It directs users to create formatted cluster spots containing the type of propagation and QTH locator.

Meteor Scatter - there are always residual random meteor trails that create ionisation, these can be used for communications over great distances using such modes as HSCW and FSK441.
The duration of these signals may be very short and only occur a few times per hour meaning that communications needs to use methods of sending information very quickly.
Examples would be sending very high speed CW or FSK441.
CW at 2/3000 letters per minute is received and slowed down to a more manageable rate decoded by ear.
FSK441 is a data mode generated and decoded by a computer and its semi automated working has made it very
popular.

Meteor shower - during certain periods of the year we can predict that the earth will encounter debris form comets. As the earth passes through this debris the number and speed of the meteors increases which means the ionisation becomes more intense.
These showers can allow SSB qso's to take place over many tens of seconds.
We refer to these as showers and typicaly become focal points where many dx expeditions take place and many keen VHF stations will be active.
The Perseides and Geminids meteor showers are major events in the VHF calendar

MGM = Machine Generated Mode. Effectively anything computer generated, FSK441, JT6M etc.

MMM - http://www.mmmonvhf.de/ make more miles on VHF is a group of enthusiasts dedicated to furthering VHF DX activity, particularly on the 2m band.
DXpedition news and activations.

MWS - Most wanted square VHF amateurs often judge their success by counting how many WWL or QRA squares they have made contact with.
Similar to collecting DXCC's on HF.
Some QRA locators are difficult to contact due to terrain or just a lack of resident amateurs.
Some enthusiasts will activate a rare square.
In order that the DXpedition targets the most difficult or most wanted square we all submit our requests to the MWS database.
Expeditions look at the squares that are wanted by the most people and target those squares for expeditions.

ODX = The most distant contact made. Usually referring to a contest or an all time best on a particular band.

OIRT = International Radio and Television Organisation (Organisation Internationale de Radiodiffusion et de Télévision) FM broadcast band used across Eastern Europe covering 65.8 - 74MHz in 30Khz steps.
Often heard in the UK giving a good indication as to the condition of 4M.
Unfortunately, often, resulting in 4M being wiped out by broadband FM signals well in excess of S9!

UKAC = United Kingdom Activity Contest. http://www.rsgbcc.org/vhf/
A series of contests taking place every Tuesday evening, 2000 - 2230 local time, involving the bands 6M through to 13cm.
Although called a contest the main intention is activity.
An opportunity for people to go on the band knowing there will be others on all over the country.
Also a means of encouraging club activities.
Although some do take the contest element relatively seriously it should not be thought of in the same, cutthroat, way as HF contests. :D

UKuG = UK Microwave Group. The representative voice microwavers in the UK.
All things above 1,000MHz. http://www.microwavers.org

Waveguide A replacement for coax cable as the frequencies get higher still.
Generally a rectangular, or oval, tube along which the signals propagate.
Can be rigid or corrugated, to allow a certain amount of bending.
Often pressurised, with dry air, in order that damp air cannot enter and effect its properties.
A pressure pump can either be permanently connected, with sensors operating, as require and starting up the compressor to keep the pressure constant, or, pressurised then valved off and periodically checked, and topped up, when needed.

WSJT = An open-source program designed for weak-signal digital communication. http://www.physics.princeton.edu/pulsar/K1JT/

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Fri Dec 17, 2010 9:31 am
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