scope:

This European Telecommunication Standard (ETS) is applicable to 625-line PAL/SECAM systems B, G, H, I, L, D and K broadcast on the VHF / UHF terrestrial networks, including their distribution on cable networks.

It specifies reference signals that may be inserted into the vertical blanking interval of the baseband video signal prior to transmission, and the way of incorporating these reference signals into the television system. These reference signals are intended for use by appropriately equipped television receivers to reduce or eliminate the effects of multi-path reception on displayed pictures and, in addition, to improve the eye-height of received teletext data so as to reduce the likelihood of errors in teletext decoding.

This ETS specifies the waveform inserted into the baseband video signal, at the point of insertion.