There is of course guidance in AC 60-11C about what you can use during the knowledge test. Nothing has changed this century so I'll bet it is the same as when A-Squared took his test. You can take a plotter or straight edge. You can take a calculator. And you can take an E6B. But you must be able to show there is nothing stored in memory in the calculator or electronic E6B. And you can not bring the instruction book for the calculator or E6B.