Other Uses
Although simultaneous substitution was conceived to substitute the signal of a foreign station, the practice has been applied as well to substitute the signal of a non-local Canadian station in a given market. For example in Montreal, the signal of Ottawa's CJOH-DT has frequently been substituted by the signal of local station CFCF-DT, even though both stations are part of the CTV network.
Simultaneous substitution has also been implemented on French language television stations. From the 1970s to the mid-1990s, TVA's flagship Montreal station CFTM-TV regularly had its signal substituting that of its Sherbrooke sister station CHLT-TV (which was obtainable in the Montreal area until 1995).
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