UPDATE: Thank you Mr. Peter Todd Decker and Mr. Gord G Rabjohn for pointing out that I had incorrectly identified the piezoelectric tuning crystal which vibrates at about 32kHz and provides a "clock" to the FM receiver. The antenna is in fact the auxiliary cord (headphones) plugged into the radio, unless an external antenna is attached. I will update the guide in the future to correct this error. The HEX 3653 Radio Chip Kit is a great way to dive in to circuits and soldering.