Fisher, Philip M. Vanishing Ships

Implausible pulp fiction about a secret Axis military base / concentration camp located off the coast of Baja California where American merchant mariners, whose ships had been captured by the Axis baddies, provide slave labor. Fisher will have his unsophisticated reader believe that the “Japs” and Nazis had been secretly hijacking American vessels in the Pacific since 1935 and that their success in doing so came from the discovery of a “secret” radio wave which, when wielded, disrupted normal marine wireless transmissions. The sadistic baddies naturally plan an attack on the West Coast (flotillas of Japanese and German U-boats are expected any day!), but are thwarted by the crew of a U.S. destroyer which has fortuitously discovered the secret base.