PORTLAND — A Cumberland County man who threatened to kill the hosts of a National Public Radio show was sentenced to 46 months in prison in U.S. District Court on Friday.

John Crosby, 38, had pleaded guilty in April to two counts of making interstate communications to injure a person and one count of unlawful possession of a firearm. He had no permanent address at the time of his arrest, but was described as being from Cape Elizabeth.

Judge George Singal sentenced Crosby to 46 months for each of the charges, to be served concurrently at a prison that can treat mental heath problems, and three years of supervised release after his prison term.

Singal noted that the 46-month sentence was a substantial one. Prosecutors requested the penalty, the maximum for Crosby under federal sentencing guidelines.

“I do that because of what I consider to be despicable conduct and a risk of danger to the public,” Singal said during the proceeding.

In January, Crosby sent more than 20 threatening messages through the NPR website, most of which included a derogatory term for Jews and some of which demanded $3 million.

Federal agents arrested Crosby that month. His lawyer wrote in a court document that Crosby had the weapon, a 20-gauge shotgun, because he had been contemplating suicide but changed his mind because of his children. Crosby was barred from having the shotgun because he had been convicted of robbery and possession of heroin.

Two of the messages Crosby sent named “All Things Considered” hosts Melissa Block and Guy Raz.

In one, Crosby used a vulgar misogynist term to refer to Block, whom he called “a commissar who is helping to destroy me to use me as human sacrifice,” and said she would soon be raped, beaten, tortured and murdered.

In another that addressed Raz, Crosby made a reference to lynching and said he would “take care of business” if he could make it to Washington, D.C.

Singal read from a portion of Block’s victim impact statement, which was sealed from public view. Block described how more than 20 gruesome messages made it clear the sender was responding violently to her.

Block’s statement came up in the context of the defense and prosecution’s disagreement about whether Block and Raz were targeted by the messages that didn’t specify them by name — an issue that would have affected the sentencing range that applied to Crosby.

John Geary, Crosby’s lawyer, argued for a 36-month sentence, saying he did not believe his client would reoffend. In a court document, Geary said Crosby believed his messages were “so over the top” that they could not be taken seriously.

The threats prompted NPR to devote substantial resources to protect employees and diverted attention away from the core mission of the organization, David Sweeney, managing editor of NPR News in Washington, told the court. Sweeney asked Singal to impose the maximum penalty and place him in a facility far from Washington, D.C.

“This has obviously been a very distressing and serious situation,” Sweeney said after the hearing.

Before Crosby read from a prepared statement, he complained about how he was characterized by Assistant U.S. Attorney Julia Lipez and in media accounts.

“I feel like I’m sort of being made into someone who’s not human,” he said.

According to the defense’s sentencing memorandum, Crosby is prone to depression, possibly from a 2001 diagnosis of Hodgkin’s lymphoma, and has been diagnosed with polysubstance dependence.

Crosby shows the “rambling, unstructured, delusional thought patterns of a disorganized psychotic,” according to an attached report from Dr. Lesley Perman-Kerr. The psychologist wrote that it’s unlikely that he has the capacity to plan, but that impulsive acts of violence can’t be ruled out, because of the combination of paranoia and possible substance abuse.

Crosby paused to compose himself several times during his statement. He described difficulties after graduating magna cum laude with a bachelor’s degree in electrical engineering from the University of Southern Maine in 2009. He left an uninspiring job at the Portsmouth Naval Shipyard and was unable to find work in the difficult economy.

In the meantime, his girlfriend gave birth to twins. He spent his days with them, but slept in his car because the children’s mother worried she could lose her subsidized housing if Crosby stayed with them.

Crosby described himself as feeling cheated and emasculated as a father. He denied being a bigot or misogynist. He felt NPR was failing to adequately cover the economic situation at a time when it was most needed.

“I am not alone,” he said. “I’m obviously alone in being someone who dealt with my anger and stress in an odd way. For that, I’m sorry.”