I signed a 1 year no compete wit a previous employer. i have heard many different possibilities of how and why this is not valid

Non-comp agreements are generally enforceable as long as they were presented 2 weeks before employment began or pursuant to an advancement at the job. Furthermore, the total amount of your annual gross salary and commissions, calculated on an annual basis, at the time of your termination needs to have exceeded the median family income for a four-person family. Even if the non-comp is legal and enforceable, to enforce the non-competition agreement the employer must pay you for the time they are attempting to enforce the non-comp, the greater of: (a) Compensation equal to at least 50 percent of your annual gross base salary and commissions at the time of your termination; or (b) Fifty percent of the median family income for a four-person family, as determined by the United States Census Bureau for the most recent year available at the time of your termination. Basically to enforce the non-comp the employer needs to pay you to not work in the industry. Good luck.