I am a law school graduate. What I offer is mere information, not to be construed as forming an attorney client relationship.
It depends on your state law. Some state laws require all parties in the conversation to be notified it is being recorded. Some states only require one party to be notified.
So, your best bet is to go to STATE LAWS at the freeadvice.com homepage and click on State Statutes. Then clikc on your state and then search there. Sometimes it is located under the evidence code or something like that.