PASSERS-BY stop and stare as Ho Wing-leung approaches the Whampoa Gardens waterfront with a metre-long flexible antenna protruding out of his handset transmitter. The bearded 27-year-old is trying to make contact. But not with extraterrestrials. Ho is demonstrating how to 'link up' with other licensed radio hobbyists or 'hams' (as they call themselves) via a designated frequency band on the crowded airwaves of Hong Kong. By standing on a less obstructed spot and using a 'telescopic' antenna, Ho's handset can reach out to fellow hams stationed as far as Mongkok or Kwun Tong on the 'ham band', which is between 144 and 146 megahertz (MHz). At 145.21MHz, his transmitter crackles. A contact is made. But rather than a fellow ham operator at the other end, Ho picks up a discussion between two foul-mouthed truck drivers about their trips to China. 'I have a consignment going up [to China] tomorrow,' a male voice says before he swears again. Moving slightly across the dial at 145.37MHz, Ho picks up another driver complaining about the lateness of the hour and having to go home to his wife. 'We get this kind of interference all the time,' says Steven Cheng, a fellow licensed ham. 'Actually, now that everyone has gone home, the interference has subsided. But during the day, it's chaotic.' 'You have truck drivers, taxi drivers, and those who simply buy their communication equipment from shops in Mongkok or Tsim Sha Tsui and mess around, switching from one band to another. 'They don't realise they may be jamming up the airwaves for other users while doing that.' Although the ham band is probably worst hit by illegal radio users, this frequency segment is not alone in suffering this problem. Today, the local airwaves are almost as crowded as Nathan Road or Causeway Bay on a Saturday night. In line with the economic boom in southern China has been an equally rapid development of its telecommunication industry - broadcasting and personal communications - as users like radio stations, mobile telephone and pager companies join the crowded airwaves. This congestion is further aggravated by the increasing number of illegal radio users, from both Hong Kong and China, tapping into the local frequency spectrum. At the moment, the frequency spectrum - from 3kHz (kilohertz) to 300GHz (gigahertz) - is allocated to 16 categories of uses. They include bands for amateur operators; satellite; radio-location, which gives the position of moving objects on land, sea or air; and bands that are allocated for land use, for example, mobile phone and pager services; and maritime and aeronautical communications. The middle-range frequency spectrum, or medium wave (from 30MHz to 300MHz), remains the most utilised and, therefore, crowded segment. That is because communication using higher frequencies often requires sophisticated, and very expensive, equipment, while the short wave (at the lower end of the spectrum) is good only for long-distance transmission. Illegal radio users are, therefore, most active on the medium wave frequencies which also accommodates the police, the Fire Services Department, the Independent Commission Against Corruption, mobile phone companies and radio stations. Sources in the broadcasting industry say bands designated for the disciplinary services such as the police and fire services are already being tapped into by illegal radio users. They fear that interference caused by illegal users in radio bands assigned for aircraft or emergencies could lead to accidents or other serious consequences. Says one: 'Some illegal users don't even know which frequencies they are trespassing because they can't see the airwaves, the bands are only numbers. 'There have been cases in which communications between the pilots and the ground control tower has been interrupted by these people. One can only speculate what would happen if this kind of important message is disrupted. 'That's why the authorities are placing a top priority in preventing interference in these bands.' But the Office of the Telecommunications Authority (OFTA) seems to take a different view. Wong Mang-hung, chief telecommunications engineer at the OFTA, plays down these fears, saying that the problem of interference in bands for aeronautical communications and disciplinary services should not be exaggerated. 'Interference in these [bands] is unavoidable. The seriousness of the problem depends on the frequency of this happening. 'There might be an interference in these bands once or twice a year. Therefore, the level of interference in these bands is tolerable,' Wong declares. 'This is by no means a serious problem. However, there have been cases in which illegal radio users have interfered with these bands on purpose but we have taken action and caught them.' Ham operators disagree. Cheng says some illegal radio users are enthusiasts who have failed the standard test for an amateur operator's licence set by City and Guilds in London. 'So it is like having a lot of drivers on a congested road without a driver's licence,' Cheng says. And the number of illegal users is on a rise, he believes. Bob Palitz, a committee member of Hong Kong Amateur Radio Transmitting Society (HARTS) and the liaison officer for International Amateur Radio Union (IARU), says the usefulness of the band assigned to amateurs is 'almost entirely destroyed' because of interference coming from illegal users. 'Most illegal users just want to talk to their friends. But the worst thing is that some use the band commercially,' he says. 'But we are left defenceless. This problem should be addressed before a disaster occurs.' While OFTA, given its limited resources, is doing a good job in catching illegal users, Palitz says the penalties imposed are not tough enough. 'The fine is a great nuisance but a small impediment for illegal users,' he says. Although offenders face a fine of up to $50,000 and two years imprisonment, the maximum penalty has never been imposed. On average illegal radio users are fined between $3,000 and $4,000, Ho says, adding that local courts do not seem to regard such activities as serious offences. 'Some truck drivers actually add their fines to their operating costs. A tougher way to deal with them is to impose a fine that has a deterrent effect or actually confiscate their vehicle,' he says. 'But to track down illegal radio users can be difficult, especially when not many of them stay on air long enough for the authorities to trace them.' OFTA's Wong Mang-hung agrees: 'How do we know who has a licence and who hasn't when the person is on air? It's not like on the road where we can just stop them and check for the licence.' Nonetheless, he insists that '99.9 per cent' of communication is successful in the broadcasting band and there is no significant interference caused by illegal users. According to Ho, a member of the 600-strong HARTS, there are about 2,000 amateur radio licence holders in Hong Kong. The ham band is only open to those with a licence. HARTS was established in the 1960s. It is a non-profit body which, besides bringing radio hobbyists together, also provides their services and expertise to community groups. Hams like Cheng are fascinated by the idea of being able to communicate with people on the other side of the globe, rather like the way the Internet is being used now by through computers. 'It's great that we can apply this traditional radio technology to help people to communicate, or mass broadcast, in both leisure activities and emergency situations,' Cheng says. 'Also, you can talk to your group of friends without leaving your house. When the night is over, you just have to switch off your machine and go to bed.' On a broader level, strong transmission signals from radio stations in southern China have also been crowding out local broadcasters in recent years. 'The Chinese stations may unintentionally take up space already allocated to local radio stations. 'Then you have a situation in which people are confused and think a local station has suddenly turned into a mainland station,' says a source in the broadcast industry. 'This situation has worsened in recent years because a large number of radio stations were set up in southern China, especially in Zhuhai and Shenzhen. 'Transmission equipment is easily obtained in these cities and you can set up a radio station in no time. Opening a radio station in China means money because of the advertising involved.' To alleviate the problem RTHK last month introduced an 'Easy Reception' service to help listeners to tune into its seven channels. Radio reception in Hong Kong has always been problematic because of the many tall buildings and mountains. 'But in recent years, as the telecommunication and broadcasting industry took off in Hong Kong and the neighbouring region, listeners have found it even more difficult to tune into our station,' it said. Lo Wai-sing, chief engineer at Hongkong Telecom International stationed in RTHK, says there are four main reasons why listeners have difficulties in locating the public broadcaster's channels. 'Some listeners don't know its frequency bands, some don't have a proper antenna, some have bad reception because of the geographical area they are in, and some are confused by new mainland channels,' he says. During Easy Reception's trial run in June, 10 per cent of the listeners who called up for the service complained that they were receiving signals from a mainland channel instead of RTHK's Radio One. Lo explains that it is not illegal for mainland stations to broadcast into the the territory but their transmission signals must not overpower bands that are already allocated to local users. 'Through OFTA, we have raised the matter with the Chinese telecommunications authorities and the situation appears to have improved,' he says. OFTA's Wong Man-hung says his office and its mainland counterpart are working closely together to ensure there are no clashes between local and mainland users in the local frequency spectrum. 'From time to time we receive complaints from the public about interference but they are mostly to do with tall buildings obstructing radio reception than interference from overseas illegal users,' he says. To ease the congestion in Hong Kong airwaves, OFTA is considering recommendations by an independent consultant to introduce spectrum fees for a selected group of users. The proposed charge is designed to encourage users in the medium wave bands to move to the higher end of the frequency spectrum. But it will do nothing to remove illegal radio users from the airwaves. Officials must face the problem which could have serious repercussions, says Ho. 'To do away with the illegal users, the Government must take some tough action against the offenders,' says the licensed enthusiast as more swearing comes through his crackling handset radio.