Leeds Crown Court heard David Rust, 71, began chatting to the 'youngster' in March last year but he was actually sending messages to an undercover police officer.
David Bradshaw, prosecuting, said Rust "groomed" him, believing him to a young teenager, gradually turning the conversation to sexual suggestions.
Rust sent explicit images and asked: "Do you like the picture?"
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The conversation went on for a month before officers went to Rust's home address at Warren House, Kirkgate, Wakefield, to arrest him.
He immediately admitted what he had done.
Rust pleaded guilty to sexual communication with a child.
The court was told that Rust had one other conviction, a sexual offence from 1990.
Satpal Roth-Sharma, mitigating, said Rust had not been seeking children specifically online, but had been living a very lonely life, and had no friends or family.
He has mobility issues and needs a mobility scooter to get around.
Judge Mushtaq Khokhar told him: "It's clear from the conversation that you had that you were grooming him.
"You're a loner who does not have any friends or contact with relatives and most of your time is spent in the house on the internet."
Rust was given a six-month prison sentence, suspended for two years, and was ordered to enroll on a sex offender programme.
He must also sign the sex offender register for seven years, and was made the subject of seven-year sexual harm prevention order (SHPO) to limit his internet use.