Implement phase correction in test file with embedded python block

3 files changed, 234 insertions, 539 deletions

diff --git a/tests/correlator/correlator.grc b/tests/correlator/correlator.grc
index 9deec54..aa21770 100644
--- a/tests/correlator/correlator.grc
+++ b/tests/correlator/correlator.grc
@@ -1,7 +1,6 @@
 options:
   parameters:
     author: Naoki Pross
-    catch_exceptions: 'True'
     category: '[GRC Hier Blocks]'
     cmake_opt: ''
     comment: ''
@@ -23,6 +22,7 @@ options:
     sizing_mode: fixed
     thread_safe_setters: ''
     title: Correlator Test
+    window_size: ''
   states:
     bus_sink: false
     bus_source: false
@@ -72,7 +72,6 @@ blocks:
     comment: ''
     const_points: '[-1-1j, -1+1j, 1+1j, 1-1j]'
     dims: '1'
-    normalization: digital.constellation.AMPLITUDE_NORMALIZATION
     precision: '8'
     rot_sym: '4'
     soft_dec_lut: None
@@ -184,42 +183,6 @@ blocks:
     coordinate: [224, 1068.0]
     rotation: 0
     state: enabled
-- name: blocks_burst_tagger_0
-  id: blocks_burst_tagger
-  parameters:
-    affinity: ''
-    alias: ''
-    comment: ''
-    false_key: nothing
-    false_value: '0'
-    maxoutbuf: '0'
-    minoutbuf: '0'
-    true_key: peak
-    true_value: 'True'
-    type: float
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [944, 1580.0]
-    rotation: 0
-    state: disabled
-- name: blocks_char_to_short_0
-  id: blocks_char_to_short
-  parameters:
-    affinity: ''
-    alias: ''
-    comment: ''
-    maxoutbuf: '0'
-    minoutbuf: '0'
-    vlen: '1'
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [752, 1624.0]
-    rotation: 0
-    state: disabled
 - name: blocks_complex_to_magphase_0
   id: blocks_complex_to_magphase
   parameters:
@@ -235,7 +198,7 @@ blocks:
     bus_structure: null
     coordinate: [1048, 696.0]
     rotation: 0
-    state: enabled
+    state: disabled
 - name: blocks_complex_to_magphase_0_0
   id: blocks_complex_to_magphase
   parameters:
@@ -249,25 +212,9 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1048, 1104.0]
+    coordinate: [1048, 1128.0]
     rotation: 0
     state: enabled
-- name: blocks_complex_to_magphase_0_1
-  id: blocks_complex_to_magphase
-  parameters:
-    affinity: ''
-    alias: ''
-    comment: ''
-    maxoutbuf: '0'
-    minoutbuf: '0'
-    vlen: '1'
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [256, 1592.0]
-    rotation: 0
-    state: disabled
 - name: blocks_multiply_const_vxx_0
   id: blocks_multiply_const_vxx
   parameters:
@@ -285,7 +232,7 @@ blocks:
     bus_structure: null
     coordinate: [1288, 724.0]
     rotation: 0
-    state: enabled
+    state: disabled
 - name: blocks_multiply_const_vxx_0_0
   id: blocks_multiply_const_vxx
   parameters:
@@ -301,41 +248,7 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1336, 1180.0]
-    rotation: 0
-    state: disabled
-- name: blocks_null_sink_0
-  id: blocks_null_sink
-  parameters:
-    affinity: ''
-    alias: ''
-    bus_structure_sink: '[[0,],]'
-    comment: ''
-    num_inputs: '1'
-    type: byte
-    vlen: '1'
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [1504, 1696.0]
-    rotation: 0
-    state: disabled
-- name: blocks_null_sink_2
-  id: blocks_null_sink
-  parameters:
-    affinity: ''
-    alias: ''
-    bus_structure_sink: '[[0,],]'
-    comment: ''
-    num_inputs: '1'
-    type: float
-    vlen: '1'
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [528, 1720.0]
+    coordinate: [1336, 1204.0]
     rotation: 0
     state: disabled
 - name: blocks_null_sink_3
@@ -352,7 +265,7 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1336, 1232.0]
+    coordinate: [1336, 1256.0]
     rotation: 0
     state: true
 - name: blocks_null_source_0
@@ -374,24 +287,6 @@ blocks:
     coordinate: [96, 344.0]
     rotation: 0
     state: enabled
-- name: blocks_peak_detector2_fb_0
-  id: blocks_peak_detector2_fb
-  parameters:
-    affinity: ''
-    alias: ''
-    alpha: '0.001'
-    comment: ''
-    look_ahead: '1000'
-    maxoutbuf: '0'
-    minoutbuf: '0'
-    threshold_factor_rise: '7'
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [528, 1620.0]
-    rotation: 0
-    state: disabled
 - name: blocks_stream_mux_0
   id: blocks_stream_mux
   parameters:
@@ -449,6 +344,22 @@ blocks:
     coordinate: [1272, 404.0]
     rotation: 0
     state: enabled
+- name: blocks_vector_sink_x_0
+  id: blocks_vector_sink_x
+  parameters:
+    affinity: ''
+    alias: ''
+    comment: ''
+    reserve_items: '1024'
+    type: byte
+    vlen: '1'
+  states:
+    bus_sink: false
+    bus_source: false
+    bus_structure: null
+    coordinate: [840, 1392.0]
+    rotation: 0
+    state: true
 - name: blocks_vector_source_x_0
   id: blocks_vector_source_x
   parameters:
@@ -457,7 +368,7 @@ blocks:
     comment: ''
     maxoutbuf: '0'
     minoutbuf: '0'
-    repeat: 'False'
+    repeat: 'True'
     tags: '[]'
     type: byte
     vector: testvec * 1600
@@ -497,7 +408,7 @@ blocks:
     block_tags: 'False'
     comment: ''
     epsilon: '1.0'
-    freq_offset: '0.000001'
+    freq_offset: '0.00001'
     maxoutbuf: '0'
     minoutbuf: '0'
     noise_voltage: '0.2'
@@ -542,9 +453,9 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1232, 1692.0]
+    coordinate: [248, 1388.0]
     rotation: 0
-    state: disabled
+    state: enabled
 - name: digital_constellation_modulator_0
   id: digital_constellation_modulator
   parameters:
@@ -558,7 +469,6 @@ blocks:
     maxoutbuf: '0'
     minoutbuf: '0'
     samples_per_symbol: sps
-    truncate: 'False'
     verbose: 'False'
   states:
     bus_sink: false
@@ -610,71 +520,87 @@ blocks:
     coordinate: [224, 836.0]
     rotation: 0
     state: enabled
-- name: fir_filter_xxx_1
-  id: fir_filter_xxx
+- name: epy_block_0
+  id: epy_block
   parameters:
+    _source_code: "import pmt\n\nimport numpy as np\nfrom gnuradio import gr\n\n\n\
+      class blk(gr.sync_block):\n    def __init__(self):\n        gr.sync_block.__init__(\n\
+      \            self,\n            name='Phase Lock',\n            in_sig=[np.complex64],\n\
+      \            out_sig=[np.complex64]\n        )\n\n        # keep track of how\
+      \ many samples were processed,\n        # because tags have an absolute offset\n\
+      \        self.sampnr: np.complex64 = 0\n\n        # because of block processing\
+      \ a tagged block could\n        # be split in half so we need to keep track\
+      \ of the\n        # \"previous\" values\n        self.last_phase = 0\n\n   \
+      \ def work(self, input_items, output_items):\n        # TODO: interpolate phase\
+      \ values for frequency correction\n\n        out = output_items[0]\n       \
+      \ inp = input_items[0]\n\n        # create a phase correction vector\n     \
+      \   phase = np.zeros(len(inp), dtype=np.float64)\n\n        # read tags\n  \
+      \      tags = self.get_tags_in_window(0, 0, len(inp))\n\n        # get only\
+      \ phase tags\n        is_phase = lambda tag: pmt.to_python(tag.key) == \"phase_est\"\
+      \n        phase_tags = list(filter(is_phase, tags))\n\n        print(f\"Processing\
+      \ {len(inp)} samples, with {len(phase_tags)} tags\")\n\n        # compute correction\
+      \ from previous block\n        first_tag = phase_tags[0]\n        first_idx\
+      \ = first_tag.offset - self.sampnr\n        phase[:first_idx] = self.last_phase\n\
+      \n        # iterate phase tags \"in the middle\"\n        for prev_tag, next_tag\
+      \ in zip(phase_tags, phase_tags[1:]):\n            # unpack pmt values\n   \
+      \         pval = pmt.to_python(prev_tag.value)\n\n            # compute indexes\
+      \ in phase vector\n            pidx = prev_tag.offset - self.sampnr\n      \
+      \      idx = next_tag.offset - self.sampnr\n\n            # compute phase correction\
+      \ for block\n            phase[pidx:idx] = pval\n            print(f\"Correction\
+      \ for block {pidx} to {idx} is {pval}\")\n\n        # compute the remaining\
+      \ part of the block\n        last_tag = phase_tags[-1]\n        last_val = pmt.to_python(last_tag.value)\n\
+      \        last_idx = last_tag.offset - self.sampnr\n\n        phase[last_idx:]\
+      \ = last_val\n\n        # save values for next call\n        self.last_phase\
+      \ = last_val\n\n        # mark samples as processed and compute to output\n\
+      \        self.sampnr += len(inp)\n        out[:] = inp * np.exp(-1j * phase)\n\
+      \n        return len(out)\n"
     affinity: ''
     alias: ''
     comment: ''
-    decim: '1'
     maxoutbuf: '0'
     minoutbuf: '0'
-    samp_delay: '0'
-    taps: revconj_access_code_symbols
-    type: ccc
   states:
+    _io_cache: ('Phase Lock', 'blk', [], [('0', 'complex', 1)], [('0', 'complex',
+      1)], '', [])
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [776, 828.0]
+    coordinate: [1088, 1040.0]
     rotation: 0
     state: enabled
-- name: high_pass_filter_0
-  id: high_pass_filter
+- name: fadingui_deframer_0
+  id: fadingui_deframer
   parameters:
     affinity: ''
     alias: ''
-    beta: '6.76'
     comment: ''
-    cutoff_freq: 5e3
-    decim: '1'
-    gain: '1'
-    interp: '1'
+    frame_obj: ''
     maxoutbuf: '0'
     minoutbuf: '0'
-    samp_rate: samp_rate
-    type: fir_filter_fff
-    width: '.7'
-    win: window.WIN_HAMMING
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [528, 1420.0]
+    coordinate: [552, 1388.0]
     rotation: 0
-    state: disabled
-- name: low_pass_filter_0
-  id: low_pass_filter
+    state: true
+- name: fir_filter_xxx_1
+  id: fir_filter_xxx
   parameters:
     affinity: ''
     alias: ''
-    beta: '6.76'
     comment: ''
-    cutoff_freq: 7e3
     decim: '1'
-    gain: '1'
-    interp: '1'
     maxoutbuf: '0'
     minoutbuf: '0'
-    samp_rate: samp_rate
-    type: fir_filter_fff
-    width: '.8'
-    win: window.WIN_HAMMING
+    samp_delay: '0'
+    taps: revconj_access_code_symbols
+    type: ccc
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [528, 1252.0]
+    coordinate: [776, 828.0]
     rotation: 0
     state: disabled
 - name: qtgui_const_sink_x_0
@@ -769,12 +695,12 @@ blocks:
     coordinate: [776, 716.0]
     rotation: 0
     state: enabled
-- name: qtgui_const_sink_x_1
+- name: qtgui_const_sink_x_0_0
   id: qtgui_const_sink_x
   parameters:
     affinity: ''
     alias: ''
-    alpha1: '.5'
+    alpha1: '1.0'
     alpha10: '1.0'
     alpha2: '1.0'
     alpha3: '1.0'
@@ -784,7 +710,7 @@ blocks:
     alpha7: '1.0'
     alpha8: '1.0'
     alpha9: '1.0'
-    autoscale: 'True'
+    autoscale: 'False'
     axislabels: 'True'
     color1: '"blue"'
     color10: '"red"'
@@ -797,7 +723,7 @@ blocks:
     color8: '"red"'
     color9: '"red"'
     comment: ''
-    grid: 'True'
+    grid: 'False'
     gui_hint: 2,1,2,1
     label1: ''
     label10: ''
@@ -810,7 +736,7 @@ blocks:
     label8: ''
     label9: ''
     legend: 'True'
-    marker1: '9'
+    marker1: '0'
     marker10: '0'
     marker2: '0'
     marker3: '0'
@@ -820,10 +746,10 @@ blocks:
     marker7: '0'
     marker8: '0'
     marker9: '0'
-    name: '"Cross Correlation"'
+    name: '"Phase Locked Signal"'
     nconnections: '1'
     size: '1024'
-    style1: '2'
+    style1: '0'
     style10: '0'
     style2: '0'
     style3: '0'
@@ -858,15 +784,15 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1048, 612.0]
+    coordinate: [1288, 940.0]
     rotation: 0
     state: enabled
-- name: qtgui_const_sink_x_2
+- name: qtgui_const_sink_x_1
   id: qtgui_const_sink_x
   parameters:
     affinity: ''
     alias: ''
-    alpha1: '1.0'
+    alpha1: '.5'
     alpha10: '1.0'
     alpha2: '1.0'
     alpha3: '1.0'
@@ -876,7 +802,7 @@ blocks:
     alpha7: '1.0'
     alpha8: '1.0'
     alpha9: '1.0'
-    autoscale: 'False'
+    autoscale: 'True'
     axislabels: 'True'
     color1: '"blue"'
     color10: '"red"'
@@ -889,8 +815,8 @@ blocks:
     color8: '"red"'
     color9: '"red"'
     comment: ''
-    grid: 'False'
-    gui_hint: '2,1,2,1 '
+    grid: 'True'
+    gui_hint: 2,1,2,1
     label1: ''
     label10: ''
     label2: ''
@@ -902,7 +828,7 @@ blocks:
     label8: ''
     label9: ''
     legend: 'True'
-    marker1: '0'
+    marker1: '9'
     marker10: '0'
     marker2: '0'
     marker3: '0'
@@ -912,10 +838,10 @@ blocks:
     marker7: '0'
     marker8: '0'
     marker9: '0'
-    name: '"Phase Correction"'
+    name: '"Cross Correlation"'
     nconnections: '1'
     size: '1024'
-    style1: '0'
+    style1: '2'
     style10: '0'
     style2: '0'
     style3: '0'
@@ -950,7 +876,7 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1248, 1588.0]
+    coordinate: [1048, 612.0]
     rotation: 0
     state: disabled
 - name: qtgui_time_sink_x_0
@@ -1049,7 +975,7 @@ blocks:
     bus_structure: null
     coordinate: [1320, 604.0]
     rotation: 0
-    state: enabled
+    state: disabled
 - name: qtgui_time_sink_x_0_0
   id: qtgui_time_sink_x
   parameters:
@@ -1144,7 +1070,7 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1336, 1084.0]
+    coordinate: [1336, 1108.0]
     rotation: 0
     state: enabled
 - name: qtgui_time_sink_x_0_0_0
@@ -1233,7 +1159,7 @@ blocks:
     width7: '1'
     width8: '1'
     width9: '1'
-    ylabel: XC Magnitude
+    ylabel: Equalized
     ymax: '2'
     ymin: '-2'
     yunit: '""'
@@ -1241,106 +1167,9 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1048, 1020.0]
+    coordinate: [1048, 940.0]
     rotation: 0
     state: enabled
-- name: qtgui_time_sink_x_1
-  id: qtgui_time_sink_x
-  parameters:
-    affinity: ''
-    alias: ''
-    alpha1: '1.0'
-    alpha10: '1.0'
-    alpha2: '1.0'
-    alpha3: '1.0'
-    alpha4: '1.0'
-    alpha5: '1.0'
-    alpha6: '1.0'
-    alpha7: '1.0'
-    alpha8: '1.0'
-    alpha9: '1.0'
-    autoscale: 'False'
-    axislabels: 'True'
-    color1: blue
-    color10: dark blue
-    color2: red
-    color3: green
-    color4: black
-    color5: cyan
-    color6: magenta
-    color7: yellow
-    color8: dark red
-    color9: dark green
-    comment: ''
-    ctrlpanel: 'False'
-    entags: 'True'
-    grid: 'False'
-    gui_hint: ''
-    label1: Signal 1
-    label10: Signal 10
-    label2: Signal 2
-    label3: Signal 3
-    label4: Signal 4
-    label5: Signal 5
-    label6: Signal 6
-    label7: Signal 7
-    label8: Signal 8
-    label9: Signal 9
-    legend: 'True'
-    marker1: '-1'
-    marker10: '-1'
-    marker2: '-1'
-    marker3: '-1'
-    marker4: '-1'
-    marker5: '-1'
-    marker6: '-1'
-    marker7: '-1'
-    marker8: '-1'
-    marker9: '-1'
-    name: '""'
-    nconnections: '1'
-    size: '1024'
-    srate: samp_rate
-    stemplot: 'False'
-    style1: '1'
-    style10: '1'
-    style2: '1'
-    style3: '1'
-    style4: '1'
-    style5: '1'
-    style6: '1'
-    style7: '1'
-    style8: '1'
-    style9: '1'
-    tr_chan: '0'
-    tr_delay: '0'
-    tr_level: '0.0'
-    tr_mode: qtgui.TRIG_MODE_FREE
-    tr_slope: qtgui.TRIG_SLOPE_POS
-    tr_tag: '""'
-    type: float
-    update_time: '0.10'
-    width1: '1'
-    width10: '1'
-    width2: '1'
-    width3: '1'
-    width4: '1'
-    width5: '1'
-    width6: '1'
-    width7: '1'
-    width8: '1'
-    width9: '1'
-    ylabel: Amplitude
-    ymax: '20'
-    ymin: '-5'
-    yunit: '""'
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [784, 1452.0]
-    rotation: 0
-    state: disabled
 - name: qtgui_time_sink_x_1_0
   id: qtgui_time_sink_x
   parameters:
@@ -1534,7 +1363,7 @@ blocks:
     bus_structure: null
     coordinate: [776, 612.0]
     rotation: 0
-    state: enabled
+    state: disabled
 - name: qtgui_time_sink_x_2
   id: qtgui_time_sink_x
   parameters:
@@ -1631,7 +1460,7 @@ blocks:
     bus_structure: null
     coordinate: [1480, 708.0]
     rotation: 0
-    state: enabled
+    state: disabled
 - name: qtgui_time_sink_x_2_0
   id: qtgui_time_sink_x
   parameters:
@@ -1726,7 +1555,7 @@ blocks:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [1512, 1164.0]
+    coordinate: [1512, 1188.0]
     rotation: 0
     state: disabled
 - name: root_raised_cosine_filter_0
@@ -1765,30 +1594,17 @@ blocks:
     coordinate: [1480, 404.0]
     rotation: 0
     state: enabled
-- name: virtual_sink_1
+- name: virtual_sink_3
   id: virtual_sink
   parameters:
     alias: ''
     comment: ''
-    stream_id: symbols
+    stream_id: locked
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [776, 916.0]
-    rotation: 0
-    state: true
-- name: virtual_sink_2
-  id: virtual_sink
-  parameters:
-    alias: ''
-    comment: ''
-    stream_id: xcorrelation
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [1080, 836.0]
+    coordinate: [1336, 1036.0]
     rotation: 0
     state: true
 - name: virtual_source_0
@@ -1804,49 +1620,29 @@ blocks:
     coordinate: [32, 884.0]
     rotation: 0
     state: enabled
-- name: virtual_source_2
-  id: virtual_source
-  parameters:
-    alias: ''
-    comment: ''
-    stream_id: symbols
-  states:
-    bus_sink: false
-    bus_source: false
-    bus_structure: null
-    coordinate: [32, 1716.0]
-    rotation: 0
-    state: disabled
-- name: virtual_source_3
+- name: virtual_source_1
   id: virtual_source
   parameters:
     alias: ''
     comment: ''
-    stream_id: xcorrelation
+    stream_id: locked
   states:
     bus_sink: false
     bus_source: false
     bus_structure: null
-    coordinate: [32, 1604.0]
+    coordinate: [24, 1388.0]
     rotation: 0
-    state: disabled
+    state: true
 
 connections:
-- [blocks_char_to_short_0, '0', blocks_burst_tagger_0, '1']
 - [blocks_complex_to_magphase_0, '0', qtgui_time_sink_x_0, '0']
 - [blocks_complex_to_magphase_0, '1', blocks_multiply_const_vxx_0, '0']
 - [blocks_complex_to_magphase_0_0, '0', qtgui_time_sink_x_0_0, '0']
 - [blocks_complex_to_magphase_0_0, '1', blocks_multiply_const_vxx_0_0, '0']
 - [blocks_complex_to_magphase_0_0, '1', blocks_null_sink_3, '0']
-- [blocks_complex_to_magphase_0_1, '0', blocks_burst_tagger_0, '0']
-- [blocks_complex_to_magphase_0_1, '0', blocks_peak_detector2_fb_0, '0']
-- [blocks_complex_to_magphase_0_1, '0', high_pass_filter_0, '0']
-- [blocks_complex_to_magphase_0_1, '0', low_pass_filter_0, '0']
-- [blocks_complex_to_magphase_0_1, '1', blocks_null_sink_2, '0']
 - [blocks_multiply_const_vxx_0, '0', qtgui_time_sink_x_2, '0']
 - [blocks_multiply_const_vxx_0_0, '0', qtgui_time_sink_x_2_0, '0']
 - [blocks_null_source_0, '0', blocks_stream_mux_0, '0']
-- [blocks_peak_detector2_fb_0, '0', blocks_char_to_short_0, '0']
 - [blocks_stream_mux_0, '0', digital_constellation_modulator_0, '0']
 - [blocks_stream_mux_1, '0', channels_channel_model_0, '0']
 - [blocks_throttle_0, '0', virtual_sink_0, '0']
@@ -1857,22 +1653,22 @@ connections:
 - [digital_cma_equalizer_cc_0, '0', fir_filter_xxx_1, '0']
 - [digital_cma_equalizer_cc_0, '0', qtgui_const_sink_x_0, '0']
 - [digital_cma_equalizer_cc_0, '0', qtgui_time_sink_x_1_1, '0']
-- [digital_cma_equalizer_cc_0, '0', virtual_sink_1, '0']
-- [digital_constellation_decoder_cb_0, '0', blocks_null_sink_0, '0']
+- [digital_constellation_decoder_cb_0, '0', fadingui_deframer_0, '0']
 - [digital_constellation_modulator_0, '0', blocks_stream_mux_1, '1']
 - [digital_constellation_modulator_0, '0', channels_channel_model_0, '0']
 - [digital_constellation_modulator_0, '0', qtgui_time_sink_x_1_0, '0']
+- [digital_corr_est_cc_0, '0', epy_block_0, '0']
 - [digital_corr_est_cc_0, '0', qtgui_time_sink_x_0_0_0, '0']
 - [digital_corr_est_cc_0, '1', blocks_complex_to_magphase_0_0, '0']
 - [digital_pfb_clock_sync_xxx_0, '0', digital_cma_equalizer_cc_0, '0']
+- [epy_block_0, '0', qtgui_const_sink_x_0_0, '0']
+- [epy_block_0, '0', virtual_sink_3, '0']
+- [fadingui_deframer_0, '0', blocks_vector_sink_x_0, '0']
 - [fir_filter_xxx_1, '0', blocks_complex_to_magphase_0, '0']
 - [fir_filter_xxx_1, '0', qtgui_const_sink_x_1, '0']
-- [fir_filter_xxx_1, '0', virtual_sink_2, '0']
-- [high_pass_filter_0, '0', qtgui_time_sink_x_1, '0']
-- [low_pass_filter_0, '0', qtgui_time_sink_x_1, '0']
 - [root_raised_cosine_filter_0, '0', blocks_stream_mux_1, '0']
 - [virtual_source_0, '0', digital_pfb_clock_sync_xxx_0, '0']
-- [virtual_source_3, '0', blocks_complex_to_magphase_0_1, '0']
+- [virtual_source_1, '0', digital_constellation_decoder_cb_0, '0']
 
 metadata:
   file_format: 1
diff --git a/tests/correlator/correlator.py b/tests/correlator/correlator.py
index 376d061..a870cc0 100755
--- a/tests/correlator/correlator.py
+++ b/tests/correlator/correlator.py
@@ -7,7 +7,7 @@
 # GNU Radio Python Flow Graph
 # Title: Correlator Test
 # Author: Naoki Pross
-# GNU Radio version: 3.9.2.0
+# GNU Radio version: 3.8.2.0
 
 from distutils.version import StrictVersion
 
@@ -28,23 +28,20 @@ import sip
 from gnuradio import blocks
 from gnuradio import channels
 from gnuradio import digital
-from gnuradio import filter
 from gnuradio import gr
-from gnuradio.fft import window
 import sys
 import signal
 from argparse import ArgumentParser
 from gnuradio.eng_arg import eng_float, intx
 from gnuradio import eng_notation
-
-
+import epy_block_0
 
 from gnuradio import qtgui
 
 class correlator(gr.top_block, Qt.QWidget):
 
     def __init__(self):
-        gr.top_block.__init__(self, "Correlator Test", catch_exceptions=True)
+        gr.top_block.__init__(self, "Correlator Test")
         Qt.QWidget.__init__(self)
         self.setWindowTitle("Correlator Test")
         qtgui.util.check_set_qss()
@@ -92,119 +89,11 @@ class correlator(gr.top_block, Qt.QWidget):
         ##################################################
         # Blocks
         ##################################################
-        self.qtgui_time_sink_x_2 = qtgui.time_sink_f(
-            1024, #size
-            samp_rate, #samp_rate
-            "", #name
-            1, #number of inputs
-            None # parent
-        )
-        self.qtgui_time_sink_x_2.set_update_time(0.10)
-        self.qtgui_time_sink_x_2.set_y_axis(-1, 1)
-
-        self.qtgui_time_sink_x_2.set_y_label('XC Phase', "")
-
-        self.qtgui_time_sink_x_2.enable_tags(True)
-        self.qtgui_time_sink_x_2.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, 0, "")
-        self.qtgui_time_sink_x_2.enable_autoscale(True)
-        self.qtgui_time_sink_x_2.enable_grid(False)
-        self.qtgui_time_sink_x_2.enable_axis_labels(True)
-        self.qtgui_time_sink_x_2.enable_control_panel(False)
-        self.qtgui_time_sink_x_2.enable_stem_plot(False)
-
-
-        labels = ['Signal 1', 'Signal 2', 'Signal 3', 'Signal 4', 'Signal 5',
-            'Signal 6', 'Signal 7', 'Signal 8', 'Signal 9', 'Signal 10']
-        widths = [1, 1, 1, 1, 1,
-            1, 1, 1, 1, 1]
-        colors = ['blue', 'red', 'green', 'black', 'cyan',
-            'magenta', 'yellow', 'dark red', 'dark green', 'dark blue']
-        alphas = [1.0, 1.0, 1.0, 1.0, 1.0,
-            1.0, 1.0, 1.0, 1.0, 1.0]
-        styles = [1, 1, 1, 1, 1,
-            1, 1, 1, 1, 1]
-        markers = [-1, -1, -1, -1, -1,
-            -1, -1, -1, -1, -1]
-
-
-        for i in range(1):
-            if len(labels[i]) == 0:
-                self.qtgui_time_sink_x_2.set_line_label(i, "Data {0}".format(i))
-            else:
-                self.qtgui_time_sink_x_2.set_line_label(i, labels[i])
-            self.qtgui_time_sink_x_2.set_line_width(i, widths[i])
-            self.qtgui_time_sink_x_2.set_line_color(i, colors[i])
-            self.qtgui_time_sink_x_2.set_line_style(i, styles[i])
-            self.qtgui_time_sink_x_2.set_line_marker(i, markers[i])
-            self.qtgui_time_sink_x_2.set_line_alpha(i, alphas[i])
-
-        self._qtgui_time_sink_x_2_win = sip.wrapinstance(self.qtgui_time_sink_x_2.pyqwidget(), Qt.QWidget)
-        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_2_win, 3, 0, 1, 1)
-        for r in range(3, 4):
-            self.top_grid_layout.setRowStretch(r, 1)
-        for c in range(0, 1):
-            self.top_grid_layout.setColumnStretch(c, 1)
-        self.qtgui_time_sink_x_1_1 = qtgui.time_sink_c(
-            1024, #size
-            samp_rate, #samp_rate
-            "", #name
-            1, #number of inputs
-            None # parent
-        )
-        self.qtgui_time_sink_x_1_1.set_update_time(0.10)
-        self.qtgui_time_sink_x_1_1.set_y_axis(-2, 2)
-
-        self.qtgui_time_sink_x_1_1.set_y_label('Equalized', "")
-
-        self.qtgui_time_sink_x_1_1.enable_tags(True)
-        self.qtgui_time_sink_x_1_1.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, 0, "")
-        self.qtgui_time_sink_x_1_1.enable_autoscale(True)
-        self.qtgui_time_sink_x_1_1.enable_grid(True)
-        self.qtgui_time_sink_x_1_1.enable_axis_labels(True)
-        self.qtgui_time_sink_x_1_1.enable_control_panel(False)
-        self.qtgui_time_sink_x_1_1.enable_stem_plot(False)
-
-
-        labels = ['Signal 1', 'Signal 2', 'Signal 3', 'Signal 4', 'Signal 5',
-            'Signal 6', 'Signal 7', 'Signal 8', 'Signal 9', 'Signal 10']
-        widths = [1, 1, 1, 1, 1,
-            1, 1, 1, 1, 1]
-        colors = ['blue', 'red', 'green', 'black', 'cyan',
-            'magenta', 'yellow', 'dark red', 'dark green', 'dark blue']
-        alphas = [1.0, 1.0, 1.0, 1.0, 1.0,
-            1.0, 1.0, 1.0, 1.0, 1.0]
-        styles = [1, 1, 1, 1, 1,
-            1, 1, 1, 1, 1]
-        markers = [-1, -1, -1, -1, -1,
-            -1, -1, -1, -1, -1]
-
-
-        for i in range(2):
-            if len(labels[i]) == 0:
-                if (i % 2 == 0):
-                    self.qtgui_time_sink_x_1_1.set_line_label(i, "Re{{Data {0}}}".format(i/2))
-                else:
-                    self.qtgui_time_sink_x_1_1.set_line_label(i, "Im{{Data {0}}}".format(i/2))
-            else:
-                self.qtgui_time_sink_x_1_1.set_line_label(i, labels[i])
-            self.qtgui_time_sink_x_1_1.set_line_width(i, widths[i])
-            self.qtgui_time_sink_x_1_1.set_line_color(i, colors[i])
-            self.qtgui_time_sink_x_1_1.set_line_style(i, styles[i])
-            self.qtgui_time_sink_x_1_1.set_line_marker(i, markers[i])
-            self.qtgui_time_sink_x_1_1.set_line_alpha(i, alphas[i])
-
-        self._qtgui_time_sink_x_1_1_win = sip.wrapinstance(self.qtgui_time_sink_x_1_1.pyqwidget(), Qt.QWidget)
-        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_1_1_win, 1, 0, 1, 1)
-        for r in range(1, 2):
-            self.top_grid_layout.setRowStretch(r, 1)
-        for c in range(0, 1):
-            self.top_grid_layout.setColumnStretch(c, 1)
         self.qtgui_time_sink_x_1_0 = qtgui.time_sink_c(
             1024, #size
             samp_rate, #samp_rate
             "", #name
-            1, #number of inputs
-            None # parent
+            1 #number of inputs
         )
         self.qtgui_time_sink_x_1_0.set_update_time(0.10)
         self.qtgui_time_sink_x_1_0.set_y_axis(-2, 2)
@@ -258,13 +147,12 @@ class correlator(gr.top_block, Qt.QWidget):
             1024, #size
             samp_rate, #samp_rate
             "", #name
-            1, #number of inputs
-            None # parent
+            1 #number of inputs
         )
         self.qtgui_time_sink_x_0_0_0.set_update_time(0.10)
         self.qtgui_time_sink_x_0_0_0.set_y_axis(-2, 2)
 
-        self.qtgui_time_sink_x_0_0_0.set_y_label('XC Magnitude', "")
+        self.qtgui_time_sink_x_0_0_0.set_y_label('Equalized', "")
 
         self.qtgui_time_sink_x_0_0_0.enable_tags(True)
         self.qtgui_time_sink_x_0_0_0.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, 0, "")
@@ -304,13 +192,12 @@ class correlator(gr.top_block, Qt.QWidget):
             self.qtgui_time_sink_x_0_0_0.set_line_alpha(i, alphas[i])
 
         self._qtgui_time_sink_x_0_0_0_win = sip.wrapinstance(self.qtgui_time_sink_x_0_0_0.pyqwidget(), Qt.QWidget)
-        self.top_layout.addWidget(self._qtgui_time_sink_x_0_0_0_win)
+        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_0_0_0_win)
         self.qtgui_time_sink_x_0_0 = qtgui.time_sink_f(
             1024, #size
             samp_rate, #samp_rate
             "", #name
-            1, #number of inputs
-            None # parent
+            1 #number of inputs
         )
         self.qtgui_time_sink_x_0_0.set_update_time(0.10)
         self.qtgui_time_sink_x_0_0.set_y_axis(0, 20)
@@ -352,72 +239,19 @@ class correlator(gr.top_block, Qt.QWidget):
             self.qtgui_time_sink_x_0_0.set_line_alpha(i, alphas[i])
 
         self._qtgui_time_sink_x_0_0_win = sip.wrapinstance(self.qtgui_time_sink_x_0_0.pyqwidget(), Qt.QWidget)
-        self.top_layout.addWidget(self._qtgui_time_sink_x_0_0_win)
-        self.qtgui_time_sink_x_0 = qtgui.time_sink_f(
+        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_0_0_win)
+        self.qtgui_const_sink_x_0_0 = qtgui.const_sink_c(
             1024, #size
-            samp_rate, #samp_rate
-            "", #name
-            1, #number of inputs
-            None # parent
+            "Phase Locked Signal", #name
+            1 #number of inputs
         )
-        self.qtgui_time_sink_x_0.set_update_time(0.10)
-        self.qtgui_time_sink_x_0.set_y_axis(0, 20)
-
-        self.qtgui_time_sink_x_0.set_y_label('XC Magnitude', "")
-
-        self.qtgui_time_sink_x_0.enable_tags(True)
-        self.qtgui_time_sink_x_0.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, 0, "")
-        self.qtgui_time_sink_x_0.enable_autoscale(True)
-        self.qtgui_time_sink_x_0.enable_grid(False)
-        self.qtgui_time_sink_x_0.enable_axis_labels(True)
-        self.qtgui_time_sink_x_0.enable_control_panel(False)
-        self.qtgui_time_sink_x_0.enable_stem_plot(False)
-
-
-        labels = ['Signal 1', 'Signal 2', 'Signal 3', 'Signal 4', 'Signal 5',
-            'Signal 6', 'Signal 7', 'Signal 8', 'Signal 9', 'Signal 10']
-        widths = [1, 1, 1, 1, 1,
-            1, 1, 1, 1, 1]
-        colors = ['blue', 'red', 'green', 'black', 'cyan',
-            'magenta', 'yellow', 'dark red', 'dark green', 'dark blue']
-        alphas = [1.0, 1.0, 1.0, 1.0, 1.0,
-            1.0, 1.0, 1.0, 1.0, 1.0]
-        styles = [1, 1, 1, 1, 1,
-            1, 1, 1, 1, 1]
-        markers = [-1, -1, -1, -1, -1,
-            -1, -1, -1, -1, -1]
-
-
-        for i in range(1):
-            if len(labels[i]) == 0:
-                self.qtgui_time_sink_x_0.set_line_label(i, "Data {0}".format(i))
-            else:
-                self.qtgui_time_sink_x_0.set_line_label(i, labels[i])
-            self.qtgui_time_sink_x_0.set_line_width(i, widths[i])
-            self.qtgui_time_sink_x_0.set_line_color(i, colors[i])
-            self.qtgui_time_sink_x_0.set_line_style(i, styles[i])
-            self.qtgui_time_sink_x_0.set_line_marker(i, markers[i])
-            self.qtgui_time_sink_x_0.set_line_alpha(i, alphas[i])
-
-        self._qtgui_time_sink_x_0_win = sip.wrapinstance(self.qtgui_time_sink_x_0.pyqwidget(), Qt.QWidget)
-        self.top_grid_layout.addWidget(self._qtgui_time_sink_x_0_win, 2, 0, 1, 1)
-        for r in range(2, 3):
-            self.top_grid_layout.setRowStretch(r, 1)
-        for c in range(0, 1):
-            self.top_grid_layout.setColumnStretch(c, 1)
-        self.qtgui_const_sink_x_1 = qtgui.const_sink_c(
-            1024, #size
-            "Cross Correlation", #name
-            1, #number of inputs
-            None # parent
-        )
-        self.qtgui_const_sink_x_1.set_update_time(0.10)
-        self.qtgui_const_sink_x_1.set_y_axis(-2, 2)
-        self.qtgui_const_sink_x_1.set_x_axis(-2, 2)
-        self.qtgui_const_sink_x_1.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, "")
-        self.qtgui_const_sink_x_1.enable_autoscale(True)
-        self.qtgui_const_sink_x_1.enable_grid(True)
-        self.qtgui_const_sink_x_1.enable_axis_labels(True)
+        self.qtgui_const_sink_x_0_0.set_update_time(0.10)
+        self.qtgui_const_sink_x_0_0.set_y_axis(-2, 2)
+        self.qtgui_const_sink_x_0_0.set_x_axis(-2, 2)
+        self.qtgui_const_sink_x_0_0.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, "")
+        self.qtgui_const_sink_x_0_0.enable_autoscale(False)
+        self.qtgui_const_sink_x_0_0.enable_grid(False)
+        self.qtgui_const_sink_x_0_0.enable_axis_labels(True)
 
 
         labels = ['', '', '', '', '',
@@ -426,26 +260,26 @@ class correlator(gr.top_block, Qt.QWidget):
             1, 1, 1, 1, 1]
         colors = ["blue", "red", "red", "red", "red",
             "red", "red", "red", "red", "red"]
-        styles = [2, 0, 0, 0, 0,
+        styles = [0, 0, 0, 0, 0,
             0, 0, 0, 0, 0]
-        markers = [9, 0, 0, 0, 0,
+        markers = [0, 0, 0, 0, 0,
             0, 0, 0, 0, 0]
-        alphas = [.5, 1.0, 1.0, 1.0, 1.0,
+        alphas = [1.0, 1.0, 1.0, 1.0, 1.0,
             1.0, 1.0, 1.0, 1.0, 1.0]
 
         for i in range(1):
             if len(labels[i]) == 0:
-                self.qtgui_const_sink_x_1.set_line_label(i, "Data {0}".format(i))
+                self.qtgui_const_sink_x_0_0.set_line_label(i, "Data {0}".format(i))
             else:
-                self.qtgui_const_sink_x_1.set_line_label(i, labels[i])
-            self.qtgui_const_sink_x_1.set_line_width(i, widths[i])
-            self.qtgui_const_sink_x_1.set_line_color(i, colors[i])
-            self.qtgui_const_sink_x_1.set_line_style(i, styles[i])
-            self.qtgui_const_sink_x_1.set_line_marker(i, markers[i])
-            self.qtgui_const_sink_x_1.set_line_alpha(i, alphas[i])
-
-        self._qtgui_const_sink_x_1_win = sip.wrapinstance(self.qtgui_const_sink_x_1.pyqwidget(), Qt.QWidget)
-        self.top_grid_layout.addWidget(self._qtgui_const_sink_x_1_win, 2, 1, 2, 1)
+                self.qtgui_const_sink_x_0_0.set_line_label(i, labels[i])
+            self.qtgui_const_sink_x_0_0.set_line_width(i, widths[i])
+            self.qtgui_const_sink_x_0_0.set_line_color(i, colors[i])
+            self.qtgui_const_sink_x_0_0.set_line_style(i, styles[i])
+            self.qtgui_const_sink_x_0_0.set_line_marker(i, markers[i])
+            self.qtgui_const_sink_x_0_0.set_line_alpha(i, alphas[i])
+
+        self._qtgui_const_sink_x_0_0_win = sip.wrapinstance(self.qtgui_const_sink_x_0_0.pyqwidget(), Qt.QWidget)
+        self.top_grid_layout.addWidget(self._qtgui_const_sink_x_0_0_win, 2, 1, 2, 1)
         for r in range(2, 4):
             self.top_grid_layout.setRowStretch(r, 1)
         for c in range(1, 2):
@@ -453,8 +287,7 @@ class correlator(gr.top_block, Qt.QWidget):
         self.qtgui_const_sink_x_0 = qtgui.const_sink_c(
             1024, #size
             "Equalized Signal", #name
-            1, #number of inputs
-            None # parent
+            1 #number of inputs
         )
         self.qtgui_const_sink_x_0.set_update_time(0.10)
         self.qtgui_const_sink_x_0.set_y_axis(-2, 2)
@@ -495,8 +328,7 @@ class correlator(gr.top_block, Qt.QWidget):
             self.top_grid_layout.setRowStretch(r, 1)
         for c in range(1, 2):
             self.top_grid_layout.setColumnStretch(c, 1)
-        self.fir_filter_xxx_1 = filter.fir_filter_ccc(1, revconj_access_code_symbols)
-        self.fir_filter_xxx_1.declare_sample_delay(0)
+        self.epy_block_0 = epy_block_0.blk()
         self.digital_pfb_clock_sync_xxx_0 = digital.pfb_clock_sync_ccf(sps, timing_loop_bw, rrc_taps, nfilts, 16, 1.5, 1)
         self.digital_corr_est_cc_0 = digital.corr_est_cc(access_code_symbols, 1, 0, .8, digital.THRESHOLD_DYNAMIC)
         self.digital_constellation_modulator_0 = digital.generic_mod(
@@ -506,59 +338,52 @@ class correlator(gr.top_block, Qt.QWidget):
             pre_diff_code=True,
             excess_bw=excess_bw,
             verbose=False,
-            log=False,
-            truncate=False)
+            log=False)
+        self.digital_constellation_decoder_cb_0 = digital.constellation_decoder_cb(const)
         self.digital_cma_equalizer_cc_0 = digital.cma_equalizer_cc(15, 1, .002, 1)
         self.channels_channel_model_0 = channels.channel_model(
             noise_voltage=0.2,
-            frequency_offset=0.000001,
+            frequency_offset=0.00001,
             epsilon=1.0,
             taps=[-1.4 + .4j],
             noise_seed=243,
             block_tags=False)
-        self.blocks_vector_source_x_0 = blocks.vector_source_b(testvec * 1600, False, 1, [])
+        self.blocks_vector_source_x_0 = blocks.vector_source_b(testvec * 1600, True, 1, [])
+        self.blocks_vector_sink_x_0 = blocks.vector_sink_b(1, 1024)
         self.blocks_throttle_0 = blocks.throttle(gr.sizeof_gr_complex*1, samp_rate,True)
         self.blocks_stream_mux_0 = blocks.stream_mux(gr.sizeof_char*1, [10, len(testvec)])
         self.blocks_null_source_0 = blocks.null_source(gr.sizeof_char*1)
         self.blocks_null_sink_3 = blocks.null_sink(gr.sizeof_float*1)
-        self.blocks_multiply_const_vxx_0 = blocks.multiply_const_ff(180 / 3.141592653589793)
         self.blocks_complex_to_magphase_0_0 = blocks.complex_to_magphase(1)
-        self.blocks_complex_to_magphase_0 = blocks.complex_to_magphase(1)
 
 
 
         ##################################################
         # Connections
         ##################################################
-        self.connect((self.blocks_complex_to_magphase_0, 1), (self.blocks_multiply_const_vxx_0, 0))
-        self.connect((self.blocks_complex_to_magphase_0, 0), (self.qtgui_time_sink_x_0, 0))
         self.connect((self.blocks_complex_to_magphase_0_0, 1), (self.blocks_null_sink_3, 0))
         self.connect((self.blocks_complex_to_magphase_0_0, 0), (self.qtgui_time_sink_x_0_0, 0))
-        self.connect((self.blocks_multiply_const_vxx_0, 0), (self.qtgui_time_sink_x_2, 0))
         self.connect((self.blocks_null_source_0, 0), (self.blocks_stream_mux_0, 0))
         self.connect((self.blocks_stream_mux_0, 0), (self.digital_constellation_modulator_0, 0))
         self.connect((self.blocks_throttle_0, 0), (self.digital_pfb_clock_sync_xxx_0, 0))
         self.connect((self.blocks_vector_source_x_0, 0), (self.blocks_stream_mux_0, 1))
         self.connect((self.channels_channel_model_0, 0), (self.blocks_throttle_0, 0))
         self.connect((self.digital_cma_equalizer_cc_0, 0), (self.digital_corr_est_cc_0, 0))
-        self.connect((self.digital_cma_equalizer_cc_0, 0), (self.fir_filter_xxx_1, 0))
         self.connect((self.digital_cma_equalizer_cc_0, 0), (self.qtgui_const_sink_x_0, 0))
-        self.connect((self.digital_cma_equalizer_cc_0, 0), (self.qtgui_time_sink_x_1_1, 0))
+        self.connect((self.digital_constellation_decoder_cb_0, 0), (self.blocks_vector_sink_x_0, 0))
         self.connect((self.digital_constellation_modulator_0, 0), (self.channels_channel_model_0, 0))
         self.connect((self.digital_constellation_modulator_0, 0), (self.qtgui_time_sink_x_1_0, 0))
         self.connect((self.digital_corr_est_cc_0, 1), (self.blocks_complex_to_magphase_0_0, 0))
+        self.connect((self.digital_corr_est_cc_0, 0), (self.epy_block_0, 0))
         self.connect((self.digital_corr_est_cc_0, 0), (self.qtgui_time_sink_x_0_0_0, 0))
         self.connect((self.digital_pfb_clock_sync_xxx_0, 0), (self.digital_cma_equalizer_cc_0, 0))
-        self.connect((self.fir_filter_xxx_1, 0), (self.blocks_complex_to_magphase_0, 0))
-        self.connect((self.fir_filter_xxx_1, 0), (self.qtgui_const_sink_x_1, 0))
+        self.connect((self.epy_block_0, 0), (self.digital_constellation_decoder_cb_0, 0))
+        self.connect((self.epy_block_0, 0), (self.qtgui_const_sink_x_0_0, 0))
 
 
     def closeEvent(self, event):
         self.settings = Qt.QSettings("GNU Radio", "correlator")
         self.settings.setValue("geometry", self.saveGeometry())
-        self.stop()
-        self.wait()
-
         event.accept()
 
     def get_sps(self):
@@ -602,12 +427,9 @@ class correlator(gr.top_block, Qt.QWidget):
     def set_samp_rate(self, samp_rate):
         self.samp_rate = samp_rate
         self.blocks_throttle_0.set_sample_rate(self.samp_rate)
-        self.qtgui_time_sink_x_0.set_samp_rate(self.samp_rate)
         self.qtgui_time_sink_x_0_0.set_samp_rate(self.samp_rate)
         self.qtgui_time_sink_x_0_0_0.set_samp_rate(self.samp_rate)
         self.qtgui_time_sink_x_1_0.set_samp_rate(self.samp_rate)
-        self.qtgui_time_sink_x_1_1.set_samp_rate(self.samp_rate)
-        self.qtgui_time_sink_x_2.set_samp_rate(self.samp_rate)
 
     def get_rrc_taps(self):
         return self.rrc_taps
@@ -621,7 +443,6 @@ class correlator(gr.top_block, Qt.QWidget):
 
     def set_revconj_access_code_symbols(self, revconj_access_code_symbols):
         self.revconj_access_code_symbols = revconj_access_code_symbols
-        self.fir_filter_xxx_1.set_taps(self.revconj_access_code_symbols)
 
     def get_const(self):
         return self.const
@@ -644,6 +465,7 @@ class correlator(gr.top_block, Qt.QWidget):
 
 
 
+
 def main(top_block_cls=correlator, options=None):
 
     if StrictVersion("4.5.0") <= StrictVersion(Qt.qVersion()) < StrictVersion("5.0.0"):
@@ -658,9 +480,6 @@ def main(top_block_cls=correlator, options=None):
     tb.show()
 
     def sig_handler(sig=None, frame=None):
-        tb.stop()
-        tb.wait()
-
         Qt.QApplication.quit()
 
     signal.signal(signal.SIGINT, sig_handler)
@@ -670,6 +489,11 @@ def main(top_block_cls=correlator, options=None):
     timer.start(500)
     timer.timeout.connect(lambda: None)
 
+    def quitting():
+        tb.stop()
+        tb.wait()
+
+    qapp.aboutToQuit.connect(quitting)
     qapp.exec_()
 
 if __name__ == '__main__':
diff --git a/tests/correlator/epy_block_0.py b/tests/correlator/epy_block_0.py
new file mode 100644
index 0000000..1fa4794
--- /dev/null
+++ b/tests/correlator/epy_block_0.py
@@ -0,0 +1,75 @@
+import pmt
+
+import numpy as np
+from gnuradio import gr
+
+
+class blk(gr.sync_block):
+    def __init__(self):
+        gr.sync_block.__init__(
+            self,
+            name='Phase Lock',
+            in_sig=[np.complex64],
+            out_sig=[np.complex64]
+        )
+
+        # keep track of how many samples were processed,
+        # because tags have an absolute offset
+        self.sampnr: np.complex64 = 0
+
+        # because of block processing a tagged block could
+        # be split in half so we need to keep track of the
+        # "previous" values
+        self.last_phase = 0
+
+    def work(self, input_items, output_items):
+        # TODO: interpolate phase values for frequency correction
+
+        out = output_items[0]
+        inp = input_items[0]
+
+        # create a phase correction vector
+        phase = np.zeros(len(inp), dtype=np.float64)
+
+        # read tags
+        tags = self.get_tags_in_window(0, 0, len(inp))
+
+        # get only phase tags
+        is_phase = lambda tag: pmt.to_python(tag.key) == "phase_est"
+        phase_tags = list(filter(is_phase, tags))
+
+        print(f"Processing {len(inp)} samples, with {len(phase_tags)} tags")
+
+        # compute correction from previous block
+        first_tag = phase_tags[0]
+        first_idx = first_tag.offset - self.sampnr
+        phase[:first_idx] = self.last_phase
+
+        # iterate phase tags "in the middle"
+        for prev_tag, next_tag in zip(phase_tags, phase_tags[1:]):
+            # unpack pmt values
+            pval = pmt.to_python(prev_tag.value)
+
+            # compute indexes in phase vector
+            pidx = prev_tag.offset - self.sampnr
+            idx = next_tag.offset - self.sampnr
+
+            # compute phase correction for block
+            phase[pidx:idx] = pval
+            print(f"Correction for block {pidx} to {idx} is {pval}")
+
+        # compute the remaining part of the block
+        last_tag = phase_tags[-1]
+        last_val = pmt.to_python(last_tag.value)
+        last_idx = last_tag.offset - self.sampnr
+
+        phase[last_idx:] = last_val
+
+        # save values for next call
+        self.last_phase = last_val
+
+        # mark samples as processed and compute to output
+        self.sampnr += len(inp)
+        out[:] = inp * np.exp(-1j * phase)
+
+        return len(out)