An ex-husband of a transsexual accused of killing her spouse by castrating him in a crude operation testified Tuesday that Tammy Felbaum had performed the procedure on him in 1983.

Lynn Ann Barner, who had a sex change after divorcing Tammy Felbaum, said she was a man known as Tim in 1983 when she asked Felbaum for the surgery. Barner said Felbaum complied.

Barner, 52, also testified that Felbaum instructed her to tell authorities that Barner had performed the operation on herself if asked.

"I was supposed to blame it on myself," said Barner, now a truck driver in Louisiana.

Felbaum, 42, is charged with third-degree murder, aggravated assault, reckless endangerment and unauthorized practice of medicine in the Feb. 25 death of James John Felbaum, 40.

Prosecutors say James Felbaum died from a combination of the surgery and painkillers at the couple's home in Marion Township, outside Harrisville, Butler County. According to court documents, Tammy Felbaum told police her sixth husband had tried to castrate himself and asked for her help.

Authorities said they found a note signed by James Felbaum saying he asked his wife to finish the procedure. Defense attorneys say he died from an overdose of painkillers including Oxycontin, not the operation.

Tammy Felbaum has told authorities she performed a similar procedure on herself at age 21 and later underwent a professional sex-change operation from male to female.

A pathologist, Dr. Karl Williams, who examined James Felbaum's body, said it was unlikely James Felbaum performed the procedure on himself. Williams added, however, that Felbaum's wounds were not infected.

Also on Tuesday, a jail guard and a state trooper who interviewed Tammy Felbaum testified that Felbaum told them she believed her husband was cheating.

"She said if he got castrated she would keep him because no one would want him," said state police Cpl. Ray Melder, who interviewed Felbaum after her arrest.

Melder also testified that Tammy admitted she wrote the note, but denied performing the surgery on her husband.

Another witness, Christine Yahnert, a guard at the Cambria County jail, where Felbaum was held in March for unpaid garbage bills before being charged in her husband's death, testified Felbaum admitted castrating him.

"In order for her to stay with him she would have to castrate him. She said she did," Yahnert testified.

Her jealousy, combined with the couple's money problems and drug abuse, caused friction in their marriage. When James Felbaum committed himself to a drug-rehabilitation program in late January, he refused to see his wife.

Tammy Felbaum also agonized over her inability to have children.

"He had kids from a previous marriage, but she wanted to carry his children. She didn't want him having children with anybody else," testified Tracy Schultz, owner of a truck wash where James Felbaum worked.

"She said she desperately wanted children," Schultz said.

James Felbaum's relatives and friends also testified Tammy Felbaum frequently threatened to castrate him, if he ever tried to leave her. Defense attorneys contend the threats were made during fits of anger or when the two were on drugs.