They believe motorists are reducing their speed as soon as they see the imitation camera – which is made out of an empty cardboard box painted yellow, stuck together with tape and attached to a pole on the side of the road.
Peter Richardson and his wife Lisa, who are responsible for the "camera", said they felt they had to act amid fears a young child could be killed. The couple want the home-made deterrent to stay until other traffic calming measures can be introduced.
The fake camera on the B4396 running through Knockin, near Oswestry, has been welcomed by residents and traders, who say they have been campaigning for years for speed enforcement measures.
But it has been criticised by road safety officials, who say they do not endorse fake cameras and urged communities to raise speed-related concerns through local councils and policing teams.
The fake camera – an empty box that a microwave came in – was set up last weekend by Mr Richardson the night before a birthday garden party for the couple's six-year-old twins James and Ruby.
There is a 30mph speed limit in force on the road, but the couple – who run the Pizza Two Four Restaurant in Oswestry and moved to Knockin in February – said motorists regularly travelled through the village at much higher speeds.
"The speed that drivers go through Knockin is crazy," Mrs Richardson said.
"We have a lot of young children and a lot of older people live here. There have already been pets killed on the road and if we don't do something ourselves I worry that a child will be next.
"We were celebrating the twins' birthday and also our first year of running Pizza Two Four with a party in the garden and Peter was really worried about the traffic."
Neighbour Ella Evans praised the couple and said it was a great idea.
"It worked straight away," she said. "The drivers seem to spot the box and slow down.
"We have such a lot of traffic going through Knockin, cars, lorries and, at this time of year, a lot of holiday traffic on the way to the coast."
Julie Stevenson, who works in the village store and post office The Knockin Shop, said she was grateful to Mr and Mrs Richardson.
"This is a busy main road and the traffic speeds through," she said. "I have certainly noticed the difference this week."
Warwickshire and West Mercia Safer Roads Partnership said it does not endorse fake cameras. It said: "All of our speed enforcement sites are carefully assessed against strict national Department for Transport criteria around suitability, traffic management and health and safety before being implemented."