Prisoner star Maggie Kirkpatrick will attempt to appeal after she was found guilty and sentenced for sexually assaulting a vulnerable teenage fan in the 1980s.

A pre-appeal mention on September 11 was listed in the County Court of Victoria, just over an hour after the 74-year-old was sentenced to an 18-month community corrections order for the assault on the girl, who was aged 14 at the time.

It is understood the mention next month will hear the grounds of the attempted appeal, as well as whether it applies to her conviction or sentence.

Maggie Kirkpatrick outside the Melbourne Magistrates' Court. (AAP) (AAP)

Melbourne Magistrate Peter Mealy sentenced Kirkpatrick, from NSW, saying she would have known the victim was especially vulnerable, as the teenager was a patient at a psychiatric hospital.

"All along to this point, as has been observed, the defendant showed no remorse - instead simply protesting at a distance, in her terms, the untrue and malicious allegations," he said today.

"The vulnerable in our society need to be protected."

Kirkpatrick will be placed on the sex offenders register for eight years and undergo treatment programs.

Maggie Kirkpatrick outside of Melbourne Magistrates' Court. (AAP) (AAP)

Mr Mealy said a jail term would have been appropriate for the significant historic offending, if it wasn't for the fact there was nothing else alleged against Kirkpatrick.

The incidents occurred while the Sydney actress was in Melbourne filming the television show Prisoner.

Her portrayal of the character Joan "The Freak" Ferguson made her a household name in Australia and won her scores of fans like the 14-year-old girl from Melbourne.

In 1984, the girl was a patient at a psychiatric hospital where she befriended a woman who also worked on the show, who introduced her to Kirkpatrick.

Top Dog Lou (Louise Siverson) and 'The Freak' (Maggie Kirkpatrick) in a tense moment during Prisoner. (AAP)

The court was told the actress collected her fan from the hospital and cooked her dinner.

Then they watched television before going to Kirkpatrick's bedroom where the actress sexually abused the girl.

When the allegations were aired last month, Kirkpatrick said they were malicious and untrue.

But Mr Mealy ruled the victim's testimony was truthful.

Kirkpatrick didn't comment as she left court.