Channel with a call to order?

HSN

This shopping network often features hosts urging viewers to pick up the phone.

The clue plays on the double meaning of "channel" and "call to order." "Channel" refers to a TV network, while "call to order" hints at the letters "H" (H for "hey," a call) and "SN" (short for "order" as in "serial number"). Together, they form "HSN," the Home Shopping Network, a well-known TV shopping channel. The wordplay cleverly combines a direct reference with a phonetic abbreviation.