Amateur radio, what it is

Kvindesland

Amateur Radio

Amateur radio or Ham radio is a common term for leasurly usage of frequencies reserved by the International Telecommunication Union for amateur radio services. This is a hobby enjoyed by houndreds of thousands all over the world. For the third world countries it offers a cheap and comprehensible method of teaching communication technology. In emergencies radio amateurs can provide contact between victims and rescue crew. However, on the daily basis, hams spend their time enjoying whichever section of their hobby they fancy. Here are a few examples:

DX contacts

The aim is to acheive contact with distant stations. One has to posess good skills in communication procedures. The distant station will have tens or houndreds of stations attempting to contact them at the same time. Therefore the successful DX-er must be able to sniff where the other part is, and fire a call at the right moment. He must also have a good knowledge of the band he is using. The propagation varies with frequency, time of day, and period of the 11-year solar cycle. Hence openings from Europe to pacific is only possible parts of the day on given bands. The clue is to know which part and what band.

The DX-er often try to establish theese contacts in order to qualify for diplomas and certificates. The contacts are rather brief. The callsign and a tecnical report of the quality of the conditions are sufficient.

You can look up a cluster to see which stations are active now.

Contesting

It's often a bit like DX work. It is really only a competition to establish as many contacts as possible during a given time. The rule of the contest explains which stations may be contacted and what information to be given. A lot of weird behaviour is heard on the bands during large contests when non-contesters answer contesters!

LA9HW has a consice list of contests you can listen to or join.

Satelite work

Radio amateur build and maintain their own satelites. Some are low orbit 90-minute paths, others are long eliptical 12 hour pass. They work on 28 MHz and above. More infor is available at the amsat page.

CW rag-chewing

This is for people who are skilled in morse transmission and reception. They have often an international circle of friends who they keep in touch with through their morse key on the short wave bands. Morse code, or CW is a very sturdy way of communicating. It requires simple equipement. The penetration through noise and lousy conditions is superb. So far it has been a prerequisit for hams wishing to use the short wave bands to demonstrate skills in telgraphy of the morse code. This may be changed in the future.

Repeaters

Many radio amateur clubs has set up 2m and 70 cm repeaters. That is devices that will receive signals from your radio and retransmit it on another frequency. This will assist your coverage. The area covered by you may be limited by tall buildings or mountains. A repeater will normally be situated at the top of sucht obstacles, and then provide the increased coverage. A lot of technical expertice and tem-work has been put into the construction and maintainance of theese repeaters.

Digital communications

After the arrival of microprocessors and computers in the radio amateur commuunity, digital communications has been high on the agenda. The main modes are:

Packet radio with AX.25, mainly on VHF and upwards
TCP/IP normally on top of AX.25.
RTTY Radio teletype. Old fashioned but works. Short wave bands
AMTOR, an amateur version of SITOR. Short wave.
GTOR, an improved version of AMTOR
CLOVER, an intelligent phase modulated short wave mode.
Hell, a vintage communication mode from WW2.

UHF/SHF work

A lot of challenges surface when you escelate the frequency to past 300 MHz Measuring instruments are few. Propagations are line of sight, but odd things may happen. A lot of home-brew takes place here in lack of things for sale. Distance records are set on 10 GHz, 47 GHz and above. Also one must not forget that in this area radio amateurs have very wide band allocation allowing for High definition TV, very fast digital trunc lines and much more.

If you want to see what sort of equipement to use for this sort of work,please look into THIS link.

Home-brew

Some hams enjoy making their own equipement. Most hams have set up an antenna they have constructet themselves. Others communicate with others through simple home-made transmitters and receivers. Often low power. And the really clever ones take on more advanced projects like power amplifiers for short wave or VHF and more. The experts produces top-of-the-range communications gear in their garden shed. My setup and projects are presented on the electronics page.

Home brewers also take computers into use. Thsi is demonstrated with DSP's etc on THIS link.

SWL listening

Alltough amateurs have their licence to transmit, some enjoys listening on the shortwave bands. There are a lot of signals to listen to. Other hams, broadcasting, maritime communication, RTTY between embassies, news agencies, weather images and much, much more. It is a bit like most of you. Have you got your own home page?

Vintage radios

Collectors buys and sells old radios. It is a large marked for WW-II sets, both allied and German sets. A lot of work has been put into doing theese sets up to working order.

In Norway may find members of Norsk Radiohistorisk Forening meeting in Korsgt. 28b, Oslo every tuesday from 18.30 to 21.30. They are available on phone 2271 4505.

QRP

In the general inferno of amateurs trying to acheive a contact. Each transmitting with at least 100 Watts. In the despair to get the contact they get more efficient antennas, and turn up th power, perhaps as much as a kW or two. Then the QRP'er will turn his power down to 10W, 5W and some times less than 1 W. To compete against the big guns will then become impossible, but with clever operating techniques and a lot of patience incredible long contacts may be worked. More info? Check G3YCC

EME

Above 50 MHz radio signals will only travel in the line of sight. The ionospheric reflective layers high up in the sky are usually not efficient on theese frequencies. Then, what if.... I see the moon on the horizon, you on the other side of the world see the same moon on your horizon. Get up as big an antenna as you can, point it at the moon. Turn on as much power you can muster and I will do the same. Then perhaps we can talk. And it works! On the good old morse code. It is called EME as in Earth- Moon-Earth.

Fox hunting

Put out some hidden transmitters in the field. Then let each contestant have his own receiver and send them out to find the transmitters. It is also known as Amateur Direction Finding or ADF.

QSL cards

Many radio amateurs exchange QSL cards to verify the contact. These may be decorated and some are more like pieces of art. They contain information about the time and date of the contact, as well as call signs and signal reports. One can also find information of which equipement they used.

Diplomas

Some amateurs collect QSL cards and qualify for diplomas for confirmed contacts with 100' countries, all continents, all of Europe, 5 hams in Vesterås in Sweeden, councils of Norway and so on. There are plenty of diplomas out there to aim for. The most known is the DXCC.