When did NHL arenas first introduce advertisements on its boards?

Question

When did NHL arenas first introduce advertisements on its boards?

Answer 1

EDIT:

The introduction of ads on arena rink boards in the late 1970s was a turning point for the NHL's ties to corporate North America, say several sports-sponsorship experts.

Some 55 years after the six hockey teams banded together to create the NHL, in 1972 The Gillette Co. wanted to build awareness for its new, twin-blade razor, the Trac 2. Gillette agreed to pay about $10,000 to place a five-metre-wide ad on the boards at centre ice in the Moscow arena where Paul Henderson and Team Canada would make history against their Soviet rivals. More than 10 million viewers tuned in to Game 8 of the series, making it one of the top-rated broadcasts in Canadian history, and making Gillette's purchase one of the marketing industry's most prescient.

It wasn't long before NHL owners were debating whether they should follow suit. The Minnesota North Stars were the first franchise to debut rink board ads. The team sold eight pairs at $3,000 a pair. Throughout the 1980s, more ads on rink boards began to sprout in NHL arenas.

Not everyone embraced the idea. In 1980, CBS televised a hockey game at Madison Square Garden in New York and refused to show any of the rink-board ads. Whenever players skated near the ads, the camera focused on the players' skates, gambling the puck would appear in the picture.

Answer 2

Probably when they first had games broadcast on television.