This is from the Pearl Harbor Myths page:
MYTH : The Opana Point Radar reported the Japanese attack 1 hour before the planes arrived over the harbor, but Adm. Kimmel refused to do anything about it.
FACT: Lt. Kermit Tyler, having ending his first tour of training at the newly established Fighter Information Center, received the report and, thinking it was a flight of B-17s due in from the mainland, told the perators to "forget it." The report went no higher than that. Interestingly enough, the new radars tracked the planes coming and going, but the Army did not tell the Navy about this pointer to the Japanese carriers until the 8th, a fact which quite possibly saved our carriers.
There are only a few people who were actually involved in either the sighting or the establishment of the Figher Information Center. Privates Lockard and Elliot were at Opana Point, Lt. Tyler was in the FIC. Other "interested parties" were Col. Bergquist, who with Col. Tindal established the FIC, and Cmdr. Taylor, USN, who was in Hawaii to teach the Navy how to use radar (and was on "loan" to the Army for the same purpose on Dec. 7th.) All of their testimonies are now available. See the documents