(written from a Production point of view)
CBS Action is currently the only British free-to-air television channel that shows regular Star Trek episodes. It was launched on 16 November 2009, in a joint venture between CBS International and Chello Zone. The channel is broadcast free-to-air on the Eurobird 1 satellite (at 28.5°E) on 11222H 27500 2/3, and is available on both Freesat and Sky, on channel 137 and 148, respectively.
Deep Space Nine
From Tuesday, 29 March to 17 June 2011, three episodes of Star Trek: Deep Space Nine were broadcast every weekday at 9am, 10am and 11am. This program is shown in the original aspect ratio. This arrangement ended Friday, 17 June 2011, as the final episode was broadcast. DS9 is therefore not currently broadcast.
Prior to Tuesday, 29 March 2011, this program was shown in the prime position slot of a single episode repeated at 1pm, 3pm and 8pm every weekday with an omnibus at 9am to 2pm every Sunday.
The Next Generation
Airing starts the 20th of July, every weekday with repeats on Sunday.
The Original Series
One episode of Star Trek: The Original Series is broadcast every weekday at 1pm, 3pm and 8pm, with each episode repeated a fourth time from 9am to 2pm every Sunday. This is the remastered version, but cropped to fit the 16:9 aspect ratio. They are shown in the airing order of the original series, starting with The Cage and moving into series 1. According to a support email, the episodes broadcast are not cut down or edited in any way - ad breaks are shorter instead.
Prior to this, two episodes of Star Trek: The Original Series were broadcast every weekday at nine and ten am. This was the remastered version, but cropped to fit the 16:9 aspect ratio. These ceased at the end of the third series on Monday, 7 March 2011.
Star Trek: Voyager will begin airing on the channel starting in 2 July 2012.