"Titanic was equipped with two 1.5 kW spark-gap wireless telegraphs located in the radio room on the Bridge Deck. One set was used for transmitting messages and the other, located in a soundproofed booth, for receiving them. The signals were transmitted through two parallel wires strung between the ship's masts, 50 feet (15 m) above the funnels to avoid the corrosive smoke." (
RMS Titanic - Wikipedia, the free encyclopedia)
So says Wikipedia.
Concerning the working hours: I once read they needed to work together, one to receive the messages from the passengers and write them down/ to write down the incoming messages for the passengers and the other one to send/ receive them. On the other hand Bride was sleeping during the collision.
Senator SMITH. Who was on duty at the wireless station from 6 o'clock Sunday evening until the collision or impact?
Mr. BRIDE. I was on duty for half an hour, sir, while Mr. Phillips went and had his dinner.
Senator SMITH. At what hour?
Mr. BRIDE. From 7 o'clock until half-past.
Senator SMITH. Where were you after that, up to the time of the collision?
Mr. BRIDE. At the time of the collision?
Senator SMITH. Up to the time of the collision.
Mr. BRIDE. I was in bed.
Senator SMITH. You had retired?
Mr. BRIDE. Yes, sir.
[...]
Senator SMITH. Then you must have been aroused somewhat by this impact?
Mr. BRIDE. No; I had promised to relieve Mr. Phillips earlier than usual, you see.
Senator SMITH. Earlier than usual, that night?
Mr. BRIDE. Yes.
Concluding from this I would say they worked together during the day (except for situations like breakfast, lunch or dinner) and worked in shifts during the nights. I don't know for sure, if anyone knows more about it please correct me, I haven't read that much until now.
The Silent room is the room where the generators for the wireless apparatus were located. The room was isolated, because the generators were pretty loud and there were some first class cabins and the officers' quarters near this room. And therefore it was called Silent room.