Only managed a 6:18:40 chip time due to some back spasms, but I finished and I got the medal to prove it! My first 9and last? TBD) marathon! And to think in August I could nto even fnish the inital 30 minute training run.
You attach a plastic thingee to your shoe that is basically a computer chip about the size of a quarter. There are mats at various points of the race including the start and it registers when yuor chip strikes the mat, so to speak (the chip doesn’t actually touch the mat, just your shoe). It’s main benefit is that it allows you to register your time not from the gun but from when you actually cross the start line. With 25,000+ people it took me almost ten minutes to get to the start line after the gun sounded. It also gives instantaneous splits that my family and freinds were able to get in updates throughout the day via email.
Right now your all hurty, but in about 2-3 weeks time you’ll want to do another one.
I believe the chip thingy is a radio transmitter. I think that when you run over the mats, which generate a magnetic field, a current is induced in the chip. That powers a radio transmitter, which sends a code to a nearby receiver.