An equalizer (34) and a prefilter (1) used in conjunction with a comb
filter (2) in a High Definition Television (HDTV) system. The prefilter
(1) may be placed before the comb filter (2), or alternatively may be
placed after the comb filter. Further, the method may be enhanced by
estimating the filter tap when the prefilter (1) is placed after the comb
filter (2). The equalizer (34) produces a fifteen level output from the
eight level Vestigial Sideband (VSB) input without limiting the amplitude
at symbol 12 to a relatively small value, such as -20 dB. Three specific
methods of increasing the permissible amplitude at symbol 12 are
presented which permit tap 12 amplitudes as high as -6 dB.