Want to catch today's Indy 500 without a TV? Fortunately, you can listen to the Indy 500 radio broadcast via the Indianapolis Motor Speedway Radio Network. The broadcast will begin from the Brickyard at 11 a.m. Eastern and carry listeners through the checkered flag and beyond.
There are a variety of ways to tune into the IMS broadcast of the Indy 500. If you have Sirius/XM satellite radio, the IMS Radio Network broadcast is available at channel 145; in and around Indianapolis, 1070-WFNI-AM carries the network. If you need to find your local affiliate, check this list of radio stations broadcasting the Indy 500 (PDF).
In case you care about history: the IMS Radio Network has been around for quite some time, first carrying an Indy 500 broadcast in 1952, and has over 400 affiliates worldwide.