Antennas aren’t just for grandma’s boob tube anymore: 19.3 percent of all US TV households get their TV fix from free over-the-air broadcasts, according to a new GfK study released this week. This means that 22.4 million households representing 59.7 million Americans get their TV for free, the market research firm estimates. The number of these over-the-air only households is growing: In 2010, only 14 percent of all households were getting their TV this way. Growth is especially strong amongst younger households, lower-income families and minorities. And once you take a closer look at those audiences, it’s really clear that free over-the-air viewing isn’t an oddity anymore, but something that’s gathering momentum quickly. GfK estimates that minorities make up for 41 percent of all antenna households. Especially mind-boggling: The majority of Latino households that primarily speak Spanish now use an antenna to get their TV programming.