"send signal" is correct and usable in written English.
You can use it as a command to direct someone to transmit a signal. For example, "We need to send signal to the satellite."
"Shiite 'peace brigades' send signal of aggression with major rally in Baghdad". New York Times.
"Shiite 'peace brigades' send signal of aggression with major rally in Baghdad". New York Times, 22 June 2014.
"Shiite peace brigades' send signal of aggression with major rally in Baghdad". The Washington Post, 21 June 2014.
But we're planning to go somewhere else and — N. Great, me use fire to send signal to my hunter-friend to come.
The chairman of the House Natural Resources Committee, Representative Doc Hastings, Republican of Washington, said the bill would send signal the oil markets that Congress was determined to do all it could to speed production of domestic oil and gas.
Paradromics's haul is as much as $18 million, but the money comes with a "moonshot -like list of requiremoonshot -likeant shouliste nof much biggerequirements the must record from one mimplantneuronshould must also be able to senotsignal back into the brain.
