A "telerecording" is the British word for a "kinescope". It was a technique used by TV companies in the years both before videotape technology was developed and after it was developed but before it was being used universally..
The following is probably something of a simplification but, essentially, much television was "live" in those days, with filmed elements inserted into, or with movie films or filmed documentaries shown between, the "live" programmes. Some programmes were pre-recorded, however, and they used the telerecording/kinescope technique.
The programme was prepared and performed "live", the visuals usually shot by several televison cameras which moved around the studio as required, and the audio recorded simultaneously by various microphones, also moving around the studio but out of sight of the cameras, of course. The director and his or her (usually his) team would cut from one camera/mike to another, as required. The output from this activity would be fed to a television monitor screen to which would be fixed a movie camera, which would film what was shown on the monitor screen. Sometimes this was done in advance, so that a programme could be shown later than it was made; sometimes, it was a technique used to preserve a programme going out live.
There is a Wiki entry on kinescopes, which is quite long. Here's a couple of bits about the use of "telerecordings" in Britain:
In the U.K., telerecordings continued to be made after the advent of commercial broadcast videotape from 1958 as they possessed several distinct advantages, particularly for overseas program sales. Firstly, they were cheaper, easier to transport and more durable than video. Secondly, they could be used in any country regardless of the television broadcasting standard, which was not true of videotape. Thirdly, the system could be used to make black and white copies of color programs for sale to television stations who were not yet broadcasting in color.
The telerecording system could be of a very high quality, easily reproducing the full detail of the television picture. The only slight disadvantage of the system was that it removed the 'fluid' look of interlaced video and 'filmized' the picture, but this would generally not have made a great deal of difference to the viewing audiences.
The system was largely used for black and white reproduction. Although some color telerecordings were made, they were generally in the minority as by the time color programmes were widely needed for sale, video standards conversion was easier and higher quality and the price of videotape had become much reduced. Before videotape became the exclusive transmission format during the early to mid-1980s, any (color) video recordings used in documentaries or filmed program inserts were usually transferred onto film.
Up until the early 1960s, much of the BBC and British television in general's output was broadcast live, and telerecordings would be used to preserve a programme for repeat showings, which had previously required the entire production being performed live for a second time.
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British broadcasters used telerecordings for domestic purposes well into the 1960s, with 35 mm being the film gauge usually used as it produced a higher quality result. For overseas sales, 16 mm film would be used, as it was cheaper. Although domestic use of telerecording in the UK for repeat broadcasts dropped off sharply after the move to color in the late 1960s, 16 mm black and white film telerecordings were still being offered for sale by British broadcasters well into the 1970s.
Telerecording was still being used internally at the BBC in the 1980s too, to preserve copies for posterity of programmes which were not necessarily of the highest importance, but which nonetheless their producers wanted to be preserved. If there were no videotape machines available on a given day, then a telerecording would be made. There is evidence to suggest that the children's magazine programme Blue Peter was occasionally being telerecorded as late as 1985. After this point, however, cheap domestic videotape formats such as VHS could more easily be used to keep a back-up reference copy of a programme.
If you ever watch old television cllips of singers and so on, you can sometimes notice something on the screen which stays there, even after the camera pans across what you're watching. If you ever see this, it is likely that there was a mark or fault on the monitor screen and this is a kinescope or telerecording.
By the time DS were appearing on TV, these systems were no longer being used, I guess.