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diff --git a/gr-atsc/lib/atsci_root_raised_cosine_bandpass.cc b/gr-atsc/lib/atsci_root_raised_cosine_bandpass.cc
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+/* -*- c++ -*- */
+/*
+ * Copyright 2002 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ *
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include <atsc/root_raised_cosine_bandpass_impl.h>
+#include <iostream>
+#include <cmath>
+
+using std::vector;
+using std::cerr;
+using std::endl;
+
+
+vector<float>
+atsc_root_raised_cosine_bandpass::taps (double sampling_freq)
+{
+
+ vector<float> t = atsc_root_raised_cosine::taps (sampling_freq);
+
+ cerr << "atsc_root_raised_cosine_bandpass::taps -- " << t.size () << endl;
+
+ // heterodyne the low pass coefficients up to the specified bandpass
+ // center frequency. Note that when we do this, the filter bandwidth
+ // is effectively twice the low pass (2.69 * 2 = 5.38) and hence
+ // matches the diagram in the ATSC spec.
+
+ double arg = 2 * M_PI * _center_freq / sampling_freq;
+ for (unsigned int i = 0; i < t.size (); i++)
+ // the factor of 2 keeps the gain of the passband normalized to 1
+ t[i] *= 2 * cos (arg * (double) i);
+
+ return t;
+}