Season 1 - 5 times

 Escape
Operations: Yesterday, two Marine guards were abducted from a South American embassy by a terrorist group called Tiburon. The spokesman for that group is a man named Cassian Perez. He sent this transmission an hour ago.

Madeline: Can we trace the transmission?

Operations: We just received another transmission.

Birkoff: This second transmission was scrambled like the first. But I put together a signal averaging program and I think we have a location.

 Noise
Gail: It's been nine minutes since the last transmission.


Season 2 - 12 times

 Hard Landing
Birkoff: As soon as operations put him in charge. the guy doesn't trust anybody, not even me. Look, he has all these transmissions locked.

Leader: Any transmission from ackerman?

Leader: Keep alternating transmissions. let me know when he calls. Reach me on channel 3.

Michael: He was a mole for the freedom league. they got to him in Singapore. It's a roll of decoded transmissions since then.

 Third Person
Michael: Was Dorset's death related to this transmission?

 Approaching Zero
Michael: Birkoff's gonna be pulling out transmission frequency. Cover as much space as you can.

Operations: Has he offered anything else since the last transmission?

 Half Life
Operations: We received an anonymous Internet transmission 2 hours before the bombing. The messages warned of further attacks but there were no accompanying demands. Was there anything on site that would help identify the group?

 Darkness Visible
Nikita: Transmission went dead. Birkoff thinks it was a land mine.

 Psychic Pilgrim
Birkoff: Here's the picture we've been able to construct so far. You were in Louis's bedroom, right here. His router is right behind this wall. I've been able to pick up fragments of his transmissions. There's definitely something in the works but the details are encoded. In order to break the code we need you to get in here. The encryption key is in a console in this room.

 Double Date
Birkoff: Michael, don't answer, the transmission is being monitored!

 Fuzzy Logic
Michael: The transmission was from a small village in South Africa.


Season 3 - 3 times

I Remember Paris
Madeline: What about the body of the transmission?

Operations: Michael, work with Birkoff. Pull off a destination on the transmission. You will head the teams. Madeline, once you're out and safe, you'll oversee Michael. Birkoff, set a clock for a hundred and twenty minutes.

Three Eyed Turtle
Birkoff: The transmission was alpha secure.


Season 4 - 4 times

 View Of The Garden
Madeline: And the transmission is a bluff. Staged by Michael.

 Love, Honor and Cherish
Birkoff: He’s been code-tagged but they’ve been able to block transmissions by restricting his exposure.

Hell Hath No Fury
Leon: You’ve intercepted a gene coded transmission. All’s fair as they say.

 Sleeping With The Enemy
RCOp1: I have a coded transmission for you from Section One. You'll need this key to unlock it.


Season 5 - 2 times

The Man Behind The Curtain
Black Colleague: Another transmission on subchannel seven. Belgrade was an anomaly. Zero impact.

Let No Man Put Asunder
Quinn: Nikita, I have no signs of any transmission. I’m sweeping for anomalies.