A Frank Spencer impersonator who took a police radio and clogged the airwaves with his comic imitations faces a possible jail sentence.

Gap-toothed charity worker Nathan Stack, 21, was collared by police who stopped his car after two days of chaos.

Winding down the window, he asked them in his finest Spencer voice: "Can I help you?"

Stack, of York Gardens, Littlehampton, arrived at Worthing Magistrates Court yesterday wearing a red beret and clutching a CB radio.

He waited outside whistling the theme tune to the Seventies sitcom Some Mothers Do 'Ave 'Em. As the charges were read, Stack turned to the public gallery, smirking and grinning.

He pleaded guilty to theft and sending false messages.

The court heard Stack swamped the Worthing police radio system with impressions of the character, remembered for his catchphrase "Ooh, Betty!"

He also answered emergency calls saying "Tango, Tango six to eight" and asked officers to repeat details of incidents.

Stack told magistrates: "I appreciate it was a very stupid thing to do but curiosity killed the cat. I'm a bit of a Frank Spencer nut and do impressions. I thought it would be funny."

He began sending the crank messages on August 11 after taking a police radio left on a counter in a petrol station.

The court heard Stack, an assistant team leader for The Prince's Trust, tuned in to police frequencies and mimicked lines by Spencer, who was played by actor Michael Crawford.

They included "Goodbye little fairies, I must leave on the double, I would like to stay for one more day but I'm in a spot of trouble".

Linda Arnell, prosecuting, said: "As a result, the control room and police had to change their radio channels." One night, Stack clogged the airwaves saying "Tango, Tango six to eight" and on August 13 intercepted an emergency transmission.

He imitated a police officer and told the control room: "Roger that, is there a description?".

When officers answered him he said: "I didn't get any of that, please repeat".

Stack was collared during the early hours of August 14 by Acting Sergeant Andy Westwood who stopped a car in Worthing.

A police radio was discovered under the driver's seat.

Mrs Arnell said: "He stated he had only intended to keep the police radio until the batteries wore down."

The court was told Stack had previous convictions, including five months in prison for taking a vehicle without authority.

Magistrates adjourned the case until October 21 for reports.

Stack was granted bail but magistrates warned him all sentencing options remained open.

After the case Stack, who plans to study electronic engineering at university next year, said: "It was a bit of an irresponsible thing to do but I couldn't help it. It was too much of an opportunity."