If someone was to make an Australian version of Forrest Gump, they might look to Brian Manning's life story for inspiration.

In 1966, he helped the Gurindji strikers in the Wave Hill walk-off. When Cyclone Tracy hit his hometown of Darwin, police commandeered his truck to collect dead bodies. Months later, he became involved in possibly the most important mission of his life.

That mission was Radio Maubere: an underground radio link that operated between Darwin and occupied East Timor during the 70s and 80s.

For many years, it was the only link the Timorese had with the outside world.

"Dad felt very strongly that these people needed to be supported in their struggle," his son, Brian Manning Jr, said.

"So with a few other people, they got together and formed this radio operation.

"It was vital. There's no doubt that the Indonesians were in there to systematically reduce the population by any means necessary.

"So these people were just killing people, and these stories had to get out."

Elaborate lengths to avoid detection

Despite the many Timorese killed by Indonesian forces on Australia's doorstep, Canberra tried hard to keep Radio Maubere off the air.

In 2003, a decade before his death, Manning wrote of the cat-and-mouse games that played out in the jungles and savannah of the Top End as he and his crew went to elaborate lengths to avoid detection by Australian authorities.

"We decided to outfit a Toyota Coaster so a Timorese operator could travel around the Top End as a tourist with an Australian companion," he wrote.

"An ideal set up, but unfortunately not executed according to instructions and the operation was blown and another radio confiscated."

Laurentino Pires and Robert Wesley-Smith coordinating Radio Maubere. ( Supplied: Robert Wesley-Smith )

Decoys used to fool authorities

As the years went on, and the list of confiscated radio transmitters grew longer and Manning's tricks became more and more creative.

"They had a few decoy vehicles. And they had a few decoy radios. And they had people rendezvous with them in the bush in certain areas," Brian Manning Jr said.

Often one person would set up the transmitter, another would come along and use it, and a third would arrive to pack it up and transport it out of danger.

For the launch of one new transmitter, journalists, a politician and supporters were invited to come and speak to the guerrillas.

They packed into three minibuses, which all set off in different directions.

"I don't think the feds were prepared for that," Brian Manning Jr said.

"Dad was a bit of an old bushie up there. He'd worked out in the bush. He knew all the back roads, and all the bits of the old highway that were still there."

New transmitters always needed

The broadcasters even devised their own coded language to communicate top secret information, remembers one of the group's members, Robert Wesley-Smith.

"They each had a book, and the code would direct them to a page or something. It was very slow ... but it was a great adventure," Mr Wesley-Smith said.

Whatever problems Manning and his crew had in Australia were nothing compared to the dangers faced by those operating on the other end, where gunshots could sometimes be heard in the background.

There was a constant need to get new transmitters into the country, and an engineer from Sydney came up with an ingenious method for avoiding detection.

"It now fell to the resourcefulness of Andrew, who created a transmitter out of a ghetto blaster," Manning wrote in his book.

"This was smuggled in to Fretilin through Dili. [Through this, they gave us] updates on Indonesian atrocities in Portuguese, which had to be translated and issued as press statements.

"As usual, the media was reluctant to use the material, again maintaining they were unconfirmed reports."

Formally recognised after conflict

As technology advanced and access to the country became easier, Radio Maubere was eventually superseded.

When journalists smuggled out footage of the Santa Cruz Massacre in 1991 the world saw in pictures the types of atrocities Radio Maubere had been relaying for years. It was a turning point in the conflict.

In 2011, the efforts of Manning, Wesley-Smith and others were formally recognised, with the Timorese government awarding them official honours.

"Dad was not in the game of supplying arms to people and perpetrating a war between our countries," Brian Manning Jr said.

"What he was about was ensuring there was a way for those people who were suffering under this regime, their voices could be heard.

"They didn't forget, the people who are in power now. They know who their friends were at the time, and it was a grave time. They felt like they were isolated alone and no one knew what was going on in their country.

"But there were people outside their country who fought hard and long struggles to keep it on the agenda."

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