This is my suggestions. "testigos" is normally used for indicators, usually LED lights, although in this case it could be time indicators on the video...

Hope this helps!

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Note added at 24 mins (2007-07-03 12:47:00 GMT)
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Hmmm... Then it sounds like something like a "control".
I have found references on Google of Continuous master tapes and copy tapes.
Maybe these could be "continuous tape copies/continuous master controls"?

Sorry I can't give you anything more specific

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Note added at 1 hr (2007-07-03 13:33:16 GMT)
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dunno, it would depend on the context. I think "continuous recording" is more general and encompasses the idea of "uncut", whereas uncut is more precise as in "unedited", and maybe the first option would be the best choice.
Check these links: these are on specific recording systems (hardware) so I don't know if they are actually relevant...
http://www.patentstorm.us/patents/6798971.html
http://www.patentstorm.us/patents/5485219-description.html
http://www.patentstorm.us/patents/5485219-description.html

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Note added at 1 hr (2007-07-03 13:56:32 GMT)
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well, it does sound correct if you check out the definition here:
http://en.wikipedia.org/wiki/Aircheck

This means it is actually the "On-air" recording, which is not the entire program but only that which has been broadcasted.
and the testigos "could" relate to the following in the description:
<em>usually there is a time-of-day graphic superimposed over the video to keep track of what aired and when it aired.</em>