Keith Geoffrey Hartley, 37, of John Street, admitted theft between 1st and 21st June at Worksop Magistrates Court on Thursday.
The court heard a search was carried out on another property and the microwave was found. The owner said he had bought it from Hartley for £10.
He was arrested and admitted taking the microwave and selling it to fund his drug habit.
Defending himself, Hartley told the court the microwave was still in its box and wasn’t being used.
He sold the court he was planning to replace the microwave before his mum needed to use it.
He was fined £75, with £50 costs and £15 victim surcharge.