De or het controlefrequentie?

The correct Dutch article is:

de controlefrequentie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use controlefrequentie

the controlefrequentiede controlefrequentie
this controlefrequentiedeze controlefrequentie
that controlefrequentiedie controlefrequentie
our controlefrequentieonze controlefrequentie
your controlefrequentiejouw controlefrequentie
every controlefrequentieelke controlefrequentie
which controlefrequentie?welke controlefrequentie?
a big controlefrequentie / the big controlefrequentieeen grote controlefrequentie, de grote controlefrequentie