LIRR assistant signal man open house

Hey all I have been invited to take the assistant signalman pre screen exam at the open house on October 31. Can anyone that has taken this test or in this position give me a idea of what is going to be on this exam or what I can start studying? I know In the letter they sent out to study basic electric theory. Thanks in advance for any info anyone can provide

Hey I'm not too sure what's on the exam but I am curious. Which asst. sig position is it for?