Lines of Communication - DSM

Lines of Communication
During a production for a show the Deputy Stage Manager would typically sit at the prompt desk with a set of cans and/or a walkie talkie to use as their primary source of communication, with cue lights as a rudimentary way to ensure actors are in their starting positions.

Comms or Cans
Cans are used by the DSM to communicate with key members of the theatrical company. The sound and lighting technicians will almost definitely have a pair as they will need to be in constant communication with the DSM, as will the stage manager. During the running of the actual show they will almost exclusively be used by the DSM to give cues to the individual disciplines unless there is an emergency. There may also be an additional set of cans somewhere downstage or backstage in case there is an emergency.
When using cans it is helpful to remember a few key phrases as part of cans etiquette. They may range between wireless headsets that can be used anywhere within the auditorium, or a headset connected to a cable that removes interference but restricts movement.

• “Quiet on cans please” other operators must respond by being quiet
• “Going off cans” when any operator leaves the headset
• “Standby LX Q 11” operator responds : “Standing By”
• “LX Q 11 Go” operator may respond “Running” if its a cue which is not obvious, or is a long fade.

(Theatrecrafts.com, 2017)

Cue Lights
Cue lights have two settings; one for 'standing by', and one for 'go.' To use the cue lights the DSM would first place them in the 'standing by' setting by pressing a button. This causes the light at both the operating position and prompt desk. The actor then 'acknowledges' the cue by flipping a switch at their end. This causes the light to go steady. At the correct time of the cue the DSM would flip another switch to turn the light green, which signals the actor that it is time to go on.
https://www.youtube.com/watch?v=w0IMHHg68Yc - The first half of the video is most relevant

Theatre Relay
A theatre relay is not included in the arsenal of every DSM but basically consists of a few different buttons that allows the DSM to send out basic paging calls to areas around the auditorium, such as the F.O.H, bar and backstage areas.

References

Images
Backstage Balletomane. (2011). A Prompt Desk. [online] Available at: https://backstageballetomane.wordpress.com/2011/01/07/a-prompt-desk/ [Accessed 28 May 2017].

Sources
Theatrecrafts.com. (2017). Calls and Cans - Theatrecrafts.com. [online] Available at: http://www.theatrecrafts.com/pages/home/topics/stage-management/calls-and-cans/ [Accessed 28 May 2017].

Backstage Balletomane. (2011). A Prompt Desk. [online] Available at: https://backstageballetomane.wordpress.com/2011/01/07/a-prompt-desk/ [Accessed 28 May 2017].