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Ten metres for the newcomer
Ten metres (28.000 - 29.700 MHz) is one of the most interesting bands available to the radio amateur. No band supports a greater variety of amateur activity than ten metres - you will hear SSB, AM, CW, FM, repeaters, satellites, DX, award-chasing, contesting and local nets at various times.
Local, interstate, and international contacts are all possible on 28 MHz. Portions of ten metres may be used by all licence grades. The band's wide open spaces and spectacular openings win it many adherents during the peak years of the sunspot cycle.
Ten metres is the HF band most prone to variations due to the eleven year sunspot cycle. During the bottom years, it is possible to go for months without hearing any overseas stations on ten, but long-distance contacts are an everyday occurrence when sunspot activity is high.
We are currently (2012) approaching the peak of sunspot cycle 24. This is good news to ten metre operators, as openings will become more frequent and produce stronger signals as we approach the sunspot peak.
A propagation mode known as sporadic-E provides contacts on ten metres during all phases of the sunspot cycle. Sporadic-E can occur at any time but is most prevalent in December - January (especially between Christmas and New Year). Distances covered typically range between 500 and 1500 kilometres, making sporadic-E a useful (but not reliable) propagation mode for contacts within Australia. Signals are often very strong. Mobile stations can do as well as home stations during a good opening.
When there is no long-distance propagation, ten metres is a good band for local operating. Noise levels are lower than on 80 or 160 metres, and antenna requirements are less (particularly for mobile stations). The lack of crowding makes also makes operating easier. The range and variety of contacts possible is enhanced if your area is lucky enough to be within range of a ten metre FM repeater or simplex gateway linked to VHF or UHF.
Beacons and repeaters
Because ten metres is 1.7 MHz wide, there is room for modes and activities that would cause interference if carried out on the lower HF bands.
One such activity is beacons. Local clubs have installed beacons to let overseas stations know when ten metres is open to their area. These beacons transmit continuously and send their callsign in Morse. Beacons can normally be found between 28.200 and 28.300 MHz. The WIA website and callbook lists Australian ten metre beacons.
A special worldwide network of beacons operates on 28.200 MHz as part of the International Beacon Project (IBP). All beacons share the one frequency and are timed so that only one transmits at a time. Australia's IBP beacon is VK6RBP in Perth. IBP beacons also operate on 20, 17, 15 and 12 metres.
Ten metres is most similar to the VHF/UHF amateur bands when it comes to FM and repeater activity. However, ten metres has the added advantage of providing international FM contacts via repeaters during high sunspot years. To use the repeaters, you need a 10 metre FM transceiver that can be set up to transmit and receive on different frequencies to accommodate the repeater's 100 kHz frequency offset. Some repeaters also need a subtone.
Repeaters permit contacts that would not ordinarily be possible. For example, a station in Sydney may not be able to hear a station in Canberra, but both may be able to communicate via a repeater in Brisbane. Repeater operation gets more interesting if the repeater is also able to retransmit signals from other bands. The four standard ten metre repeater channels in use around the world are listed below.
* Input 29.520, Output 29.620 MHz
There's even orbiting repeaters, aka amateur satellites. Many of the earlier OSCAR and Russian (RS) satellites had a downlink between 29.3 and 29.5 MHz. You'd transmit on other bands, such as 15 or 2 metres and hear yourself (and others) on 10 metres. There's not as many as there used to be but it may still be worth listening.
Commercial equipment
All current-model HF transceivers cover the entire ten metre amateur band and can accommodate at least SSB, CW and digital modes.
Budget HF-only rigs (such as the Icom 718) sometimes lack FM. Other rigs had provision for it as an optional module. I'm not a great fan of ten metres FM due to its annoying fading
and inefficiency compared to SSB. However when signals are good the audio reproduction of distant signals can be stunning. It's like a lottery. If FM is your thing make sure your
rig also has a repeater offset and CTCSS subtone.
Those whose budget does not extend to the price tag of a new multiband transceiver may wish to consider buying a 28 MHz-only set. Transceivers like these would
be particularly suitable for mobile/portable operation or as a second rig for the 10 metre enthusiast. However, the dearer ones cost not much less than a basic used multiband SSB transceiver on the
second-hand market. In my book that makes them poor value. The newcomer to amateur radio should consider the extent to which they will want the other HF bands before buying a 10 metre-only set.
A few manufacturers offer VHF/UHF FM multiband mobile transceivers that also offer 10m FM. These are potentially handy if you have a busy local 10m FM repeater. Otherwise not having SSB on 10m
excludes you from the vast bulk of activity on the band.
Be careful when buying secondhand gear. Some very old tube / valve transceivers did not cover ten metres at all. Other models did include ten metres, but had deaf receivers and/or put out reduced
power on 28 MHz.
Some older (1970s) sets covered only a single 500 kHz segment of ten metres. A 28.000 - 28.500 MHz range is not a great limitation as it includes coverage of CW, digital, beacon and popular SSB
frequencies. However a set that tunes 28.500 - 29.000 MHz only is severely disadvantaged and should be avoided.
Converted equipment
If you have sufficient technical knowledge and the required information (Reference One), it is possible to convert some models of 27 MHz SSB CB transceivers to operate on 28 MHz. If the modification is done properly, the results obtained are well worth the small cost involved. Some of the older AM-only sets can also be converted to ten metres, but this is not usually worthwhile unless you want local contacts only or have a special interest in AM operating.
It is also possible to convert sets to operate on 29 MHz FM. Either some types of AM-only 27 MHz CB radios or 30-50 MHz FM two-way radios can be converted. The need for coverage of the correct frequency range and inclusion of a 100 kHz repeater offset are complicating factors here.
You probably shouldn't attempt any but the very simplest modifications if you are a newcomer - it is very easy to mistakenly 'butcher' the set and render it permanently inoperative. If you still need a small cheap ten metre set, get someone else to do the modification for you, look for a used, already-converted CB (price range $10 - 100).
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Books by VK3YE
Ham Radio Get Started (USA)Australian Ham Radio Handbook (Aust) More Hand-carried QRP Antennas 99 things you can do with Amateur Radio Getting back into Amateur Radio Illustrated International Ham Radio Dictionary Make your Passion Pay (ebook writing)
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