You don't say what type of Box you are going to, or where it imight be, which would help.
I was in a Gr2, lever frame Box and we had on average 4 trains an hour during the day shift, so you were on your feet delaing with the bells and levers for roughly 40 minutes of that hour, if they were equally spaced out. (they often weren't!) Between 2300 and 0600 things were a lot quieter. We were also dealing with 3 user worked farm crossings plus dealing with telephone calls from track workers, etc. It could get quite busy especially if there were faults occuring at the same time.
Yes there were gaps but that gave you time to make sure the paperwork was up to date, that the Box was clean, and gave you time to go to the loo and make a meal or a drink.
Was it boring? Yes sometimes, just as it is in any job, but it is very easy to find something to do. Many signallers read or even do model making. I even know of two signallers that wrote books in the slack periods, especially at night.