Radio airwaves get buzzed from pot

Radio airwaves get buzzed from pot By Trevor Hughes,

A few years ago, retired electrical engineer Tom Thompson noticed it was
getting harder and harder to hear his friends across the country talking to
him on their ham radio sets. So Thompson built a portable antenna system to
track down whatever was interfering with his radio transmission.

The culprit? Marijuana grow operations, whose powerful grow lights can emit
interference blocking radio broadcasts on the ham and AM spectrums.

The first grower he encountered wasn’t pleased to know Thompson, now 73,
could tell what was going on. “He said, ‘What are you going to do, call the
cops?’ Thompson said. “And I said, ‘Well no, it’s a federal matter.

‘ With 22 states and the District of Columbia allowing medical marijuana,
and Colorado and Washington permitting recreational use, there’s been an
explosion in the number of people growing their own pot, much of it indoors.
With that growth has come increasing interference from the grow lights,
which suck down huge amounts of electricity to shine upon budding marijuana
plants. Growing pot indoors is usually more secure and gives the grower more
control over light, water and insects, which results in higher-quality
plants commanding a premium price.

The interference problems from one type of system have gotten so bad that
the amateur radio association, ARRL, filed a formal federal complaint on
behalf of the country’s 720,000 licensed ham operators. The problems are
worse in Colorado and California, said Sean Kutzko, an ARRL spokesman.

The interference is caused by what are known as “ballasts,” electronic
systems controlling the grow lights. Unless they’re properly shielded, the
ballasts can throw off a wide range of interference. “We’re seeing numerous
cases … and that’s causing us a problem,” Kutzko said. “We just want to
make sure the manufacturers are in compliance with FCC laws. The FCC has the
power to regulate anything that interferes with licensed radio
transmissions, such as ham sets, but also cellphones and AM radios.