Gateway to Amateur Radio
Gateway to Amateur Radio
Contents
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Frequently asked questions
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Licence-free activities
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Getting licensed
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First contacts
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Branching out
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Projects & technical
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News
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ACMA
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WIA
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Gateway to Am. Radio Home
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First Contacts: Seven essential steps
You won't find material this specific published anywhere else and I'd encourage you to read it in full at some time. However if you just want to get on air quickly, zoom down to the 'Peter's Picks' for ideas that work.
If you're anything like me when I started, you won't have a clue. So I'll answer the question for you. My guess is that you just want to get on air and talk to wide range of people. Right now it doesn't matter much where they are, but you do want to be heard and for there to be someone around any time you switch on.
You'll recall that you can choose between HF bands at 3.5, 7, 21 and 28 MHz. On VHF you have 144 MHz and on UHF 430 MHz. You can run 10 watts power, which is modest but usable. It's easy to buy a radio to cover all these bands but antennas are a different story. When setting up a station first pick one or two bands only. Antennas can be added for more bands later. When making your choice, only select bands that offer consistently high activity during the times you wish to operate. A quick rundown of available bands is as follows: 3.5 MHz (80 metres): Busiest at night but also activity late afternoons and early mornings. Reliable contacts up to 500km, with occasional contacts up to 3000 km. Needs at least 30 metres of yard space for an efficient wire antenna. 7 MHz (40 metres): Consistently active during mornings, daytime and afternoon. Less evening activity than 80 metres. Reliable contacts up to 1000 km, with occasional international contacts. Needs at least 15 metres of yard space for an efficient wire antenna. 21 MHz (15 metres): Provides daytime interstate and international contacts during high sunspot years. Inconsistent activity at other times. 28 MHz (10 metres): Provides daytime interstate and international contacts during high sunspot years. Little activity at other times. FM repeaters in some areas provide variety. 144 MHz (2 metres): Active morning to night in the larger cities. Good clear local coverage; FM transmit range is typically 20 to 50 km with longer range during temperature inversions. SSB or repeaters extend range up to 150 km. Internet linking in some areas. Mast or pole required for vertical or beam antenna. 430 MHz (70 centimetres): Similar characteristics to two metres but generally less activity, less transmitting range and higher feedline losses. FM repeaters and internet linking in some areas. Mast or pole required for vertical or beam antenna. Peter's Picks
Don't bother about 21, 28 and 430 MHz. These bands have their attractions but consistently high activity is not one of them. That leaves 3.5, 7 and 144 MHz. If you're in a country area more than 50 km from a major city, drop 144 MHz off the list. Otherwise consider it for the local communication it offers. If space is limited, pick 7 MHz over 3.5 MHz in the interests of antenna efficiency. Otherwise it is fine to start on 3.5 MHz, and later add a shorter wire for 7 MHz to provide efficient operation on at least these two bands. Similarly if you have 144 MHz, many transceivers and antennas also cover 430 MHz and it would be silly not to have this band available as well.
There are many fancy antennas around and it is possible to part with a lot of money for no increase in performance. Despite wild claims, no magic ingredient exists and many expensive multiband antennas are inferior to what can be made at home. This section will discuss suitable starter antennas for both HF and VHF. HF Despite the range of antenna types, but on HF the basic horizontal half-wave dipole is as good as any and better than many. It comprises of two equal lengths of wire, fed with coaxial cable in the middle. Mount it high and in the clear if possible. Unless you have very tall towers don't worry too much about orientation; it won't make much difference. For 3.5 MHz (80 metres) it is almost exactly 40 metres from end to end, while the 7 MHz (40 metres) version is 20 metres from end to end. If you cannot fit the whole length in a straight line it is fine to bend the wire at the ends. If you only have one tall pole, use this for the apex and erect it as an 'inverted-V', with the ends drooping below the feed point apex. It can be made to operate on several bands by running extra wires off the one feedpoint. For example a dipole with 2x20 metre wires and 2x10 metre wires is ideal since it will work efficiently on both 80 and 40 metres. As a bonus the 7 MHz section will also radiate on 21 MHz for reasons explained elsewhere. VHF/UHF For two metres FM some sort of omnidirectional vertical antenna is a good first choice. The well-known 1/4 or 5/8 wave ground plane mounted as high as possible with as good a cable as you can afford will be fine. Commercially-made vertical antennas conveniently provide both 144 and 430 MHz coverage, but are dearer to buy and offer less gain than a home-made beam. Beams are good but require a rotator, which puts them beyond the 'simple starter station' criteria. With all antennas, avoid dissimilar metals being in contact with one another and use sealants to prevent moisture ruining the cable and increasing losses. For handheld radios, a quarter wavelength whip made from about 480 mm of stiff wire soldered to a BNC plug can boost its performance on 144 MHz. You can do the same on 430 MHz, but in this case the length is only about 160 mm. Specially-made antennas for amateur handhelds are also available off the shelf. Some of these cover both VHF and UHF, thus avoiding the need to change antennas when operation on the other band is desired. The most foolproof 144 MHz mobile antenna is a 1/4 wavelength whip (also 480mm) mounted in the centre of the car's roof or on the roof rack. 5/8 wavelength whips are longer (over a metre) and provide somewhat better performance, but can be damaged by trees and low garage doors. Mounting location is even more important than the antenna chosen; though people bauk at drilling holes in the middle of the car's roof, it really needs to be done to guarantee top results. Mobile antennas for both 144 and 430 MHz exist but they are either a compromise or expensive to buy. With all types of VHF/UHF antennas feedline loss is a constant threat to performance. A bad feedline swallows up half or more of your transmitter power (even before it gets to the antenna) and degrades reception. Loss is determined by the length and quality of the coaxial feedline, with thicker cables being less lossy than thinner cables. Before using long runs of cable, use look-up tables to see if the loss is acceptable. A loss of less than 1dB (20% of power) is good, 2dB (36% loss) usable but not optimum, while 3 dB (half your power) is poor. Sure, you'll still get contacts with a 3dB loss, but given the 10 watt power limit, isn't it better to ensure that most reaches the antenna? Peter's Picks For a setup that's guaranteed to work well first off, yet is amenable to extension later, I suggest the following: HF: Two half wave dipoles fed with the one coaxial cable feedline. If you have the room a 3.5 and 7 MHz dipole combo is ideal since it provides excellent performance on both main HF Foundation Licence bands while being usable on 21 MHz. If you're pushed for space, just build it for 7 MHz (again usable on 21 MHz). VHF home: For general FM work it's hard to go past a 1/4 or 5/8 wavelength ground plane mounted as high as possible fed with good feedline. An antenna at gutter height will get you on the air, but higher is better. Raising it to say 10 metres is like tripling your transmit power and will almost double transmit and receive range. Thin RG-58 feedline will work but could lose half your power, so the thick RG-213 is preferred. VHF mobile: A 480 mm quarter wavelength mobile whip mounted in the centre of the car roof is good, simple and cheap for 144 MHz. For similar reasons for 7 MHz dipoles operating on 21 MHz, they are usable (though not optimum) on 430 MHz. Because the feedline run is short, the thin RG-58 is acceptable. The above system of parallel dipoles for the HF bands and verticals for VHF is simple, low-cost, reproducible yet performs well on all popular Foundation Licence bands. Unless your needs and circumstances vary radically from those stated above, don't consider anything else until later.
The basic elements of all amateur stations are a regulated power supply, transceiver, antenna feedline and antenna. We've already discussed antennas and feedlines. Of these the transceiver is the dearest and most complex, while both the power supply and antenna can be made at home. Power supplies The power supply used for radio equipment ranges from internal batteries for portable transceivers, the car battery for mobile installations to 13.8 volt regulated power supplies at home. The batteries used in portable sets are small and light, but don't last long if you talk a lot at the radio's maximum power output level. For extended period portable operating, it's better to add a larger external battery connected to the radio via a cable. If your transceiver can take 12 volts through its external power socket (check first), a 12 volt 7 amp hour gel battery will give hours of operating time. Chargers for gel batteries are available off the shelf or can be assembled at home. If using mobile equipment at home, a 13.8 volt high current regulated power supply is a must. Though a 4 to 6 amp supply will power any transceiver delivering the Foundation power limit, think very carefully before spending much on building or buying one. Unless it is useful for other purposes, such a supply represents false economy if you upgrade your licence and want to run higher power. Instead, pay more for a 20 to 25 amp supply; its value will become apparent sooner than you think. HF transceivers If buying new, the Yaesu FT-817 provides all-band operation within Foundation power limits. The Icom 703 is another contender, though it is basically an HF box only. Second hand buyers look for popular low-power HF transceivers like the Yaesu FT-7, FT-77S, FT-301S and Kenwood TS-120V. All of these were produced around 25 years ago. Though still serviceable (if they have been looked after) disadvantages of this generation of transceiver include omission of some bands, frequency drift, bulk and weight. Also rigs that old may not be supported by local service agents. For more information on HF equipment, read the newly revised Your First HF Transceiver article. VHF/UHF transceivers 144 MHz operators can choose between handheld, mobile and home station-type transceivers. Most cover 430 MHz with some also including 50 MHz. A handheld unit has limited range, power output and battery capacity, so is not generally recommended as an 'only transceiver'. Instead it might be wiser to purchase a mobile unit and install it at home with a regulated power supply. Although hand held units appear cheaper, by the time accessories such as cases, larger battery packs, microphones, etc have been purchased, the total cost can exceed that of the better performing mobile transceiver. Mobile sets also offer better front-end filtering than handhelds and sometimes offer detachable front panels so the main radio unit can be placed elsewhere. Like their smaller mobile cousins, most of the larger home station transceivers run more than the 10 watt power limit but can be turned down. These rigs can often operate SSB voice as as the more common FM voice. The SSB and CW (Morse) produced is exactly the same as heard on the HF bands and is good for long-distance and satellite operation. Most home station transceivers currently on the market generally include coverage of the HF bands as well as VHF/UHF, so they are a good choice for the amateur seeking a 'do everything' transceiver. However, these transceivers normally still require the use of an external high current 13.8 volt regulated power supply to operate. Power output is another important consideration when buying a transceiver, particularly a hand-held. All the mobile and base station units put out sufficient power, but some of the micro handhelds put out only a few hundred milliwatts. These radios are enticing due to their micro size and low price. Depending on how you look at it, having only milliwatts available can be great fun or a frustrating limitation. Before buying a micro rig, do a test with a friend's set to confirm that the low power is sufficient to cover the distances you need, especially if it will be your only transceiver. A feature worth having is CTCSS encode. CTCSS puts a low-pitched audio tone on your transmission. It is useful because some repeaters in the larger cities require you to send this tone before it will retransmit your signal. This is particularly so for repeater systems in high-RF areas or those which are linked to repeaters on bands such as six and ten metres. CTCSS decode is nice to have but not essential. Its main use is to reduce false triggering of your mute if you're in a high-RF environment. It only works if the repeaters in your area have a CTCSS tone on their output signal. Some microphones include a DTMF (or touch-tone) keypad. DTMF is a tone signalling system the same as that used on your home telephone. Typical applications include remote control, repeater linking and automatic phone patching. The spread of internet repeater linking now makes the DTMF microphone a highly desirable feature. See Amateur Radio magazine for new transceivers and trader websites such as vkham and eBay for examples of used equipment.
The basic principle is to operate without causing interference to others. This relies on the use of band plans and people following agreed procedure in relation to starting, conducting and ending contacts. Band plans are necessary since equipment set up for one mode often cannot receive another. Also, since they encourage a gathering of activity around particular frequencies or band segments, people using a particular mode can more easily find others to talk to. Within this basic 'non-interference' principle there are slight differences between various band and mode sub-groups. The two main ones for Foundation Licensees are HF SSB and VHF/UHF FM voice. HF SSB can be broken down into the terse DX/Contest working and more leisurely 'ragchewing' activities. VHF/UHF FM operating has differences between simplex, repeater and internet repeater contacts. Morse (CW) and VHF/UHF SSB have their own specific procedures, but again the general principal is similar to other modes. Because you won't have memorised everything first-up, you need:
- A list of operating privileges, as set out in the Licence Condition Determination document from the ACMA All can be downloaded off the internet, but the WIA Callbook provides the information in a more accessible form, so is preferred. A clock, notepaper and/or a log book are all desirable but not mandatory.
Obtaining contacts Make contacts by doing any of the following:
- Answer a station calling CQ Since Foundation Licensees will be using lower power and their signal may be weaker than average, many of the operating tips over at The Australian QRP Home Page are relevant. Most times, 'tail-ending' has proved the most successful. It is wise to exercise discretion about matters discussed on air. In particular anything involving advertising or commercial dealings is strictly 'off limits'. Otherwise content is limited only to conventions of polite conversation, given that others can listen in. Those with more than one amateur in the family should take special care with security; announcing on the local repeater that 'the key is just under the doormat' is asking for trouble. Criminals have scanners, and your address is on the ACMA's internet database and in the callbook. Existing amateurs almost always welcome CBers to their ranks, but are not kindly disposed to hearing CB jargon on on amateur frequencies. Plain language is much better. Don't ever say 'My personal is.....'; instead say 'My name is .....'. However the term 'handle' for 'name' is used, probably because it penetrates inteference better. When you wish to join a conversation in progress, just announce your callsign in between transmissions; never say 'break' or 'break break' unless it is an emergency. The related term 'Breaker' has no meaning in amateur parlance. Finally it is desirable to avoid overusing the Q-code on voice modes - QSL? VHF/UHF variations The main differences between HF and VHF/UHF operating are as follows: - Channels on VHF/UHF. Similar to UHF CB, the FM sections of VHF and UHF amateur bands are divided into 'channels' spaced at 25 kHz intervals. Unlike the more free-ranging HF bands, if you call on a frequency that is not a designated calling channel, net frequency or repeater, you will most likely not get a response. - Calling CQ. For some strange reason, it is 'not the done thing' to CQ on repeaters in some areas. Rather it is more common for people to announce that they are 'listening'. If you hear someone announce that they are listening, treat this as a CQ call and respond accordingly. - Originating contacts. Conversations (QSOs) can be initiated either directly, on a simplex frequency (eg 146.500, 439.000 MHz), or via a repeater. In most places, you have a better chance of success by calling on a repeater. Check that the transceiver's frequency offset is switched in and correct for the repeater you intend using; some use offsets different to those specified in the Bandplan. - Small local groups. You will notice little 'tribes' congregating on various frequencies, particularly repeaters in the larger cities. Although many monitor repeaters, and talk if called, comparatively few will respond to a random call. Some new amateurs perceive this behaviour as cliquishness. Ways around this include joining conversations where you have a point relevant to the topic, involvement with a clubs or volunteering for the repeater group. Others simply prefer the variety of a larger group and use HF instead. - Repeaters. A lot of amateur VHF/UHF communication takes place through repeater stations. Repeaters consist of a receiver, transmitter, filters, and antenna. They are normally on high spots and are maintained by volunteer clubs or groups. Repeaters receive a signal (often from a mobile or hand-held transceiver), and retransmit it on an adjacent frequency, so it can be heard over a much wider area. This means that with low power and small antennas it is possible to communicate with people up to 100 to 150 km away, provided that you are within the service area of your local repeater. Once contact has been established on a repeater, it is courteous to move to a simplex frequency if possible; this makes the repeater available to those unable to do so. Another reason why simplex operation is preferred is that repeaters have time-outs, so you could find yourself cut off if you enjoy long overs on repeaters. - Internet linking. Though VHF/UHF is normally limited to local coverage, its reach can be extended worldwide thanks to internet linking. Systems used include Echolink and the Internet Repeater Linking Project. These systems are commonly fitted to local repeaters and can be user-switched to any other connected node.
Active amateurs are encouraged to join the Wireless Institute of Australia for the following reasons: - Receipt of Amateur Radio magazine. This contains the news, articles and ideas you need to keep abreast of developments in amateur radio - Your membership assists efforts to retain and enhance amateur privileges in the face of government and commercial pressures - Services such as awards, contests, QSL Bureaux, the videotape library and others
If you studied for your amateur licence through a club-sponsored class, you will already have some idea of the activities of radio clubs. Apart from running exams and licence classes, clubs also promote amateur activity by maintaining repeaters, holding technical workshops and lectures, developing club projects, running hamfests, entering contests, publicising amateur radio to the general public and more. Clubs are a good way of becoming involved in amateur activities in your local area. A listing of clubs is provided on the WIA website.
Even within the conditions of the Foundation licence, there is scope for a wide range of activities including antenna experimentation, HF DXing, contesting, low power operating, foxhunting, portable operation and construction (antennas, receivers and accessories only). Participation in one or more of these facets of our hobby is highly rewarding. The practical experience gained will also make it much easier to move to a higher grade of licence, as your interest develops. Information on most of these topics is available via links from this website.
This article was revised and rewritten in 2006 due to licensing changes. Earlier versions were published in the WIA 2000 Yearbook and Novice Notes for October 1995.
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