After initially pleading not guilty to his offences, Jarrod Westlake returned to Truro Crown Court where he admitted cutting the internet cables, as well as burglary and thefts.
The prosecutor said that on April 5 this year, alarms went off notifying authorities of malicious damage to the internet network in Falmouth.
He said around 60 customers were affected, including high profile businesses such as Wetherspoons and Bet Fred.
Boots and Holland & Barrett could also not access their systems, resulting in medical transactions being cancelled.
READ MORE: Teamwork restores Falmouth broadband after vandalism threatened Easter trade
CCTV showed Westlake cutting wires, and this was also witnessed by members of the public.
One man saw the defendant cutting wires with garden secateurs, while a woman saw him outside the Wetherspoon pub on The Moor, and asked him if he should be doing that.
“He said he worked for BT and offered her a job,” said the prosecutor, who added that the woman “felt slightly threatened by that.”
Open Reach said that the loss of internet affected a community hub supporting vulnerable residents, in addition to the medical issues experienced.
There was £24,000 of damage caused to the wires, with a further cost of £35,000 for the emergency repair work, resulting in an overall loss of £59,000.
Westlake, who represented himself in court, said: “There was never intent in my actions. I’m sincerely sorry.”
The 34-year-old explained that his medication was not appropriate at the time.
Westlake was also sentenced for burglary and theft, the first of which took place March 2 this year, at Tesco Falmouth.
He asked for two packets of cigarettes, but when given them he simply walked out the shop without paying.
Then on March 15, also at Tesco Falmouth, he picked up a bottle of vodka in the store and drank from it.
He subsequently wandered in to a restricted area for staff and contractors, found some cider and drank from that too.
Judge Simon Carr said a psychiatric report showed Westlake suffered from psychosis, ADHD, anxiety and depression.
“Clearly you were very ill indeed when you committed these offences,” he told Westlake, before adding: “However, these were serious offences.
“In the crime against BT, you cut the phone line of a huge portion of [the town], putting people at risk and causing significant damage.”
He said Westlake had already spend a “significant period of time in custody on remand,” and his sentence would allow the defendant to get the support the probation service was offering.
Judge Carr sentenced Westlake to 12 months in prison, suspended for two years, for the damage to the internet cables, and a further four months in prison, suspended for two years, for the burglary.
Westlake must complete 50 days of rehabilitation activities in the next year, to address his issues.