Module: PWN::Plugins::GQRX

Defined in:
lib/pwn/plugins/gqrx.rb

Overview

This plugin interacts with the remote control interface of GQRX.

Class Method Summary collapse

Class Method Details

.assume_profile(opts = {}) ⇒ Object

Supported Method Parameters

opts = PWN::Plugins::GQRX.assume_profile(

profile: 'required - valid GQRX profile name returned from #list_profiles method'

)



600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
# File 'lib/pwn/plugins/gqrx.rb', line 600

public_class_method def self.assume_profile(opts = {})
  profile = opts[:profile].to_s.to_sym

  profiles_available = list_profiles
  opts = {}
  case profile
  when :ads_b978
    opts = profiles_available[:ads_b978]
  when :ads_b1090
    opts = profiles_available[:ads_b1090]
  when :analog_tv_vhf
    opts = profiles_available[:analog_tv_vhf]
  when :analog_tv_uhf
    opts = profiles_available[:analog_tv_uhf]
  when :am_radio
    opts = profiles_available[:am_radio]
  when :bluetooth
    opts = profiles_available[:bluetooth]
  when :cdma
    opts = profiles_available[:cdma]
  when :cw20
    opts = profiles_available[:cw20]
  when :cw40
    opts = profiles_available[:cw40]
  when :cw80
    opts = profiles_available[:cw80]
  when :gps12
    opts = profiles_available[:gps12]
  when :gps15
    opts = profiles_available[:gps15]
  when :gsm
    opts = profiles_available[:gsm]
  when :fm_radio
    opts = profiles_available[:fm_radio]
  when :high_rfid
    opts = profiles_available[:high_rfid]
  when :lora433
    opts = profiles_available[:lora433]
  when :lora915
    opts = profiles_available[:lora915]
  when :low_rfid
    opts = profiles_available[:low_rfid]
  when :keyfob300
    opts = profiles_available[:keyfob300]
  when :keyfob310
    opts = profiles_available[:keyfob310]
  when :keyfob315
    opts = profiles_available[:keyfob315]
  when :keyfob390
    opts = profiles_available[:keyfob390]
  when :rtty20
    opts = profiles_available[:rtty20]
  when :rtty40
    opts = profiles_available[:rtty40]
  when :rtty80
    opts = profiles_available[:rtty80]
  when :ssb10
    opts = profiles_available[:ssb10]
  when :ssb12
    opts = profiles_available[:ssb12]
  when :ssb15
    opts = profiles_available[:ssb15]
  when :ssb17
    opts = profiles_available[:ssb17]
  when :ssb20
    opts = profiles_available[:ssb20]
  when :ssb40
    opts = profiles_available[:ssb40]
  when :ssb80
    opts = profiles_available[:ssb80]
  when :ssb160
    opts = profiles_available[:ssb160]
  when :tempest
    opts = profiles_available[:tempest]
  when :wifi24
    opts = profiles_available[:wifi24]
  when :zigbee
    opts = profiles_available[:zigbee]
  else
    raise "ERROR: Invalid profile: #{profile}"
  end

  opts
rescue StandardError => e
  raise e
end

.authorsObject

Author(s)

0day Inc. <[email protected]>



701
702
703
704
705
# File 'lib/pwn/plugins/gqrx.rb', line 701

public_class_method def self.authors
  "AUTHOR(S):
    0day Inc. <[email protected]>
  "
end

.connect(opts = {}) ⇒ Object

Supported Method Parameters

gqrx_sock = PWN::Plugins::GQRX.connect(

target: 'optional - GQRX target IP address (defaults to 127.0.0.1)',
port: 'optional - GQRX target port (defaults to 7356)'

)



14
15
16
17
18
19
20
21
# File 'lib/pwn/plugins/gqrx.rb', line 14

public_class_method def self.connect(opts = {})
  target = opts[:target] ||= '127.0.0.1'
  port = opts[:port] ||= 7356

  PWN::Plugins::Sock.connect(target: target, port: port)
rescue StandardError => e
  raise e
end

.disconnect(opts = {}) ⇒ Object

Supported Method Parameters

PWN::Plugins::GQRX.disconnect(

gqrx_sock: 'required - GQRX socket object returned from #connect method'

)



691
692
693
694
695
696
697
# File 'lib/pwn/plugins/gqrx.rb', line 691

public_class_method def self.disconnect(opts = {})
  gqrx_sock = opts[:gqrx_sock]

  PWN::Plugins::Sock.disconnect(sock_obj: gqrx_sock)
rescue StandardError => e
  raise e
end

.gqrx_cmd(opts = {}) ⇒ Object

Supported Method Parameters

gqrx_resp = PWN::Plugins::GQRX.gqrx_cmd(

gqrx_sock: 'required - GQRX socket object returned from #connect method',
cmd: 'required - GQRX command to execute',
resp_ok: 'optional - Expected response from GQRX to indicate success'

)



30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
# File 'lib/pwn/plugins/gqrx.rb', line 30

public_class_method def self.gqrx_cmd(opts = {})
  gqrx_sock = opts[:gqrx_sock]
  cmd = opts[:cmd]
  resp_ok = opts[:resp_ok]

  # Most Recent GQRX Command Set:
  # https://raw.githubusercontent.com/gqrx-sdr/gqrx/master/resources/remote-control.txt
  # Supported commands:
  #  f Get frequency [Hz]
  #  F <frequency> Set frequency [Hz]
  #  m Get demodulator mode and passband
  #  M <mode> [passband]
  #     Set demodulator mode and passband [Hz]
  #     Passing a '?' as the first argument instead of 'mode' will return
  #     a space separated list of radio backend supported modes.
  #  l|L ?
  #     Get a space separated list of settings available for reading (l) or writing (L).
  #  l STRENGTH
  #     Get signal strength [dBFS]
  #  l SQL
  #     Get squelch threshold [dBFS]
  #  L SQL <sql>
  #     Set squelch threshold to <sql> [dBFS]
  #  l AF
  #     Get audio gain [dB]
  #  L AF <gain>
  #     Set audio gain to <gain> [dB]
  #  l <gain_name>_GAIN
  #     Get the value of the gain setting with the name <gain_name>
  #  L <gain_name>_GAIN <value>
  #     Set the value of the gain setting with the name <gain_name> to <value>
  #  p RDS_PI
  #     Get the RDS PI code (in hexadecimal). Returns 0000 if not applicable.
  #  u RECORD
  #     Get status of audio recorder
  #  U RECORD <status>
  #     Set status of audio recorder to <status>
  #  u DSP
  #     Get DSP (SDR receiver) status
  #  U DSP <status>
  #     Set DSP (SDR receiver) status to <status>
  #  u RDS
  #     Get RDS decoder to <status>.  Only functions in WFM mode.
  #  U RDS <status>
  #     Set RDS decoder to <status>.  Only functions in WFM mode.
  #  q|Q
  #     Close connection
  #  AOS
  #     Acquisition of signal (AOS) event, start audio recording
  #  LOS
  #     Loss of signal (LOS) event, stop audio recording
  #  LNB_LO [frequency]
  #     If frequency [Hz] is specified set the LNB LO frequency used for
  #     display. Otherwise print the current LNB LO frequency [Hz].
  #  \chk_vfo
  #     Get VFO option status (only usable for hamlib compatibility)
  #  \dump_state
  #     Dump state (only usable for hamlib compatibility)
  #  \get_powerstat
  #     Get power status (only usable for hamlib compatibility)
  #  v
  #     Get 'VFO' (only usable for hamlib compatibility)
  #  V
  #     Set 'VFO' (only usable for hamlib compatibility)
  #  s
  #     Get 'Split' mode (only usable for hamlib compatibility)
  #  S
  #     Set 'Split' mode (only usable for hamlib compatibility)
  #  _
  #     Get version
  #
  # Reply:
  #  RPRT 0
  #     Command successful
  #  RPRT 1
  #     Command failed

  gqrx_sock.write("#{cmd}\n")
  response = []
  got_freq = false
  # Read all responses from gqrx_sock.write
  timeout = 0.001 if timeout.nil?

  begin
    response.push(gqrx_sock.readline.chomp) while gqrx_sock.wait_readable(timeout)
    raise IOError if response.empty?
  rescue IOError
    timeout += 0.001
    retry
  end

  got_int_value_in_resp = true if response.first.to_i.positive?
  response = response.first if response.length == 1

  raise "ERROR!!! Command: #{cmd} Expected Resp: #{resp_ok}, Got: #{response}" if resp_ok && response != resp_ok

  if got_int_value_in_resp
    fixed_len_freq = format('%0.12d', response.to_i)
    freq_segments = fixed_len_freq.scan(/.{3}/)
    first_non_zero_index = freq_segments.index { |s| s.to_i.positive? }
    freq_segments = freq_segments[first_non_zero_index..-1]
    freq_segments[0] = freq_segments.first.to_i.to_s
    response = freq_segments.join('.')
  end

  # DEBUG
  # puts response.inspect
  # puts response.length

  response
rescue RuntimeError => e
  puts 'WARNING: RF Gain is not supported by the radio backend.' if e.message.include?('Command: L RF_GAIN')
  puts 'WARNING: Intermediate Gain is not supported by the radio backend.' if e.message.include?('Command: L IF_GAIN')
  puts 'WARNING: Baseband Gain is not supported by the radio backend.' if e.message.include?('Command: L BB_GAIN')

  raise e unless e.message.include?('Command: L RF_GAIN') ||
                 e.message.include?('Command: L IF_GAIN') ||
                 e.message.include?('Command: L BB_GAIN')
rescue StandardError => e
  raise e
end

.helpObject

Display Usage for this Module



709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
# File 'lib/pwn/plugins/gqrx.rb', line 709

public_class_method def self.help
  puts "USAGE:
    gqrx_sock = #{self}.connect(
    target: 'optional - GQRX target IP address (defaults to 127.0.0.1)',
      port: 'optional - GQRX target port (defaults to 7356)'
    )

    #{self}.gqrx_cmd(
      gqrx_sock: 'required - GQRX socket object returned from #connect method',
      cmd: 'required - GQRX command to execute',
      resp_ok: 'optional - Expected response from GQRX to indicate success'
    )

    #{self}.init_freq(
      gqrx_sock: 'required - GQRX socket object returned from #connect method',
      freq: 'required - Frequency to set',
      demodulator_mode: 'optional - Demodulator mode (defaults to WFM)',
      bandwidth: 'optional - Bandwidth (defaults to 200000)',
      lock_freq_duration: 'optional - Lock frequency duration (defaults to 0.5)',
      strength_lock: 'optional - Strength lock (defaults to -60.0)'
    )

    #{self}.scan_range(
      gqrx_sock: 'required - GQRX socket object returned from #connect method',
      demodulator_mode: 'required - Demodulator mode',
      bandwidth: 'required - Bandwidth',
      start_freq: 'required - Starting frequency',
      target_freq: 'required - Target frequency',
      precision: 'required - Precision',
      lock_freq_duration: 'optional - Lock frequency duration (defaults to 0.5)',
      strength_lock: 'optional - Strength lock (defaults to -60.0)'
    )

    profiles = #{self}.list_profiles

    opts = #{self}.assume_profile(
      profile: 'required - valid GQRX profile name returned from #list_profiles method'
    )

    #{self}.disconnect(
      gqrx_sock: 'required - GQRX socket object returned from #connect method'
    )

    #{self}.authors
  "
end

.init_freq(opts = {}) ⇒ Object

Supported Method Parameters

PWN::Plugins::GQRX.init_freq(

gqrx_sock: 'required - GQRX socket object returned from #connect method',
freq: 'required - Frequency to set',
demodulator_mode: 'optional - Demodulator mode (defaults to WFM)',
bandwidth: 'optional - Bandwidth (defaults to 200000)',
lock_freq_duration: 'optional - Lock frequency duration (defaults to 0.5)',
strength_lock: 'optional - Strength lock (defaults to -60.0)'

)



161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
# File 'lib/pwn/plugins/gqrx.rb', line 161

public_class_method def self.init_freq(opts = {})
  gqrx_sock = opts[:gqrx_sock]
  freq = opts[:freq]
  demodulator_mode = opts[:demodulator_mode]
  bandwidth = opts[:bandwidth]
  lock_freq_duration = opts[:lock_freq_duration]
  strength_lock = opts[:strength_lock]

  demod_n_passband = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'm'
  )

  change_freq_resp = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: "F #{freq}",
    resp_ok: 'RPRT 0'
  )

  current_freq = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'f'
  )

  audio_gain_db = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'l AF'
  ).to_f

  current_strength = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'l STRENGTH'
  ).to_f

  current_squelch = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'l SQL'
  ).to_f

  rf_gain = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'l RF_GAIN'
  ).to_f

  if_gain = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'l IF_GAIN'
  ).to_f

  bb_gain = gqrx_cmd(
    gqrx_sock: gqrx_sock,
    cmd: 'l BB_GAIN'
  ).to_f

  init_freq_hash = {
    demod_mode_n_passband: demod_n_passband,
    frequency: current_freq,
    bandwidth: bandwidth,
    audio_gain_db: audio_gain_db,
    squelch: current_squelch,
    rf_gain: rf_gain,
    if_gain: if_gain,
    bb_gain: bb_gain,
    strength: current_strength,
    strength_lock: strength_lock,
    lock_freq_duration: lock_freq_duration
  }

  print '.'
  sleep lock_freq_duration if current_strength > strength_lock

  init_freq_hash
rescue StandardError => e
  raise e
end

.list_profilesObject

Supported Method Parameters

profiles = PWN::Plugins::GQRX.list_profiles



333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
# File 'lib/pwn/plugins/gqrx.rb', line 333

public_class_method def self.list_profiles
  # TODO: Wifi5 / Wifi6 profiles,
  # migrate to a YAML file, and add
  # rSpec test to ensure all profiles
  # contain consistent key-value pairs
  {
    ads_b978: {
      start_freq: '978.000.000',
      target_freq: '979.000.000',
      demodulator_mode: :RAW,
      bandwidth: '1.000.000',
      precision: 5
    },
    ads_b1090: {
      start_freq: '1.090.000.000',
      target_freq: '1.091.000.000',
      demodulator_mode: :RAW,
      bandwidth: '1.000.000',
      precision: 5
    },
    analog_tv_vhf: {
      start_freq: '54.000.000',
      target_freq: '216.000.000',
      demodulator_mode: :WFM,
      bandwidth: '6.000',
      precision: 5
    },
    analog_tv_uhf: {
      start_freq: '470.000.000',
      target_freq: '890.000.000',
      demodulator_mode: :WFM,
      bandwidth: '6.000',
      precision: 5
    },
    am_radio: {
      start_freq: '540.000',
      target_freq: '1.700.000',
      demodulator_mode: :AM,
      bandwidth: '10.000',
      precision: 4
    },
    bluetooth: {
      start_freq: '2.400.000.000',
      target_freq: '2.485.000.000',
      demodulator_mode: :RAW,
      bandwidth: '1.000.000',
      precision: 5
    },
    cdma: {
      start_freq: '824.000.000',
      target_freq: '849.000.000',
      demodulator_mode: :RAW,
      bandwidth: '1.250.000',
      precision: 6
    },
    cw20: {
      start_freq: '14.000.000',
      target_freq: '14.350.000',
      demodulator_mode: :CW,
      bandwidth: '150',
      precision: 3
    },
    cw40: {
      start_freq: '7.000.000',
      target_freq: '7.300.000',
      demodulator_mode: :CW,
      bandwidth: '150',
      precision: 3
    },
    cw80: {
      start_freq: '3.500.000',
      target_freq: '3.800.000',
      demodulator_mode: :CW,
      bandwidth: '150',
      precision: 3
    },
    gps12: {
      start_freq: '1.227.600.000',
      target_freq: '1.227.700.000',
      demodulator_mode: :RAW,
      bandwidth: '2.000.000',
      precision: 6
    },
    gps15: {
      start_freq: '1.575.420.000',
      target_freq: '1.575.450.000',
      demodulator_mode: :RAW,
      bandwidth: '2.000.000',
      precision: 6
    },
    gsm: {
      start_freq: '935.000.000',
      target_freq: '960.000.000',
      demodulator_mode: :RAW,
      bandwidth: '200.000',
      precision: 4
    },
    fm_radio: {
      start_freq: '88.000.000',
      target_freq: '108.000.000',
      demodulator_mode: :WFM,
      bandwidth: '200.000',
      precision: 5
    },
    high_rfid: {
      start_freq: '13.560.000',
      target_freq: '13.570.000',
      demodulator_mode: :RAW,
      bandwidth: '2.000.000',
      precision: 3
    },
    lora433: {
      start_freq: '432.000.000',
      target_freq: '434.000.000',
      demodulator_mode: :RAW,
      bandwidth: '500.000',
      precision: 3
    },
    lora915: {
      start_freq: '914.000.000',
      target_freq: '916.000.000',
      demodulator_mode: :RAW,
      bandwidth: '500.000',
      precision: 3
    },
    low_rfid: {
      start_freq: '125.000',
      target_freq: '125.100',
      demodulator_mode: :RAW,
      bandwidth: '200.000',
      precision: 1
    },
    keyfob300: {
      start_freq: '300.000.000',
      target_freq: '300.100.000',
      demodulator_mode: :RAW,
      bandwidth: '50.000',
      precision: 4
    },
    keyfob310: {
      start_freq: '310.000.000',
      target_freq: '310.100.000',
      demodulator_mode: :RAW,
      bandwidth: '50.000',
      precision: 4
    },
    keyfob315: {
      start_freq: '315.000.000',
      target_freq: '315.100.000',
      demodulator_mode: :RAW,
      bandwidth: '50.000',
      precision: 4
    },
    keyfob390: {
      start_freq: '390.000.000',
      target_freq: '390.100.000',
      demodulator_mode: :RAW,
      bandwidth: '50.000',
      precision: 4
    },
    rtty20: {
      start_freq: '14.000.000',
      target_freq: '14.350.000',
      demodulator_mode: :RTTY,
      bandwidth: '170',
      precision: 3
    },
    rtty40: {
      start_freq: '7.000.000',
      target_freq: '7.300.000',
      demodulator_mode: :RTTY,
      bandwidth: '170',
      precision: 3
    },
    rtty80: {
      start_freq: '3.500.000',
      target_freq: '3.800.000',
      demodulator_mode: :RTTY,
      bandwidth: '170',
      precision: 3
    },
    ssb10: {
      start_freq: '28.000.000',
      target_freq: '29.700.000',
      demodulator_mode: :USB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb12: {
      start_freq: '24.890.000',
      target_freq: '24.990.000',
      demodulator_mode: :USB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb15: {
      start_freq: '21.000.000',
      target_freq: '21.450.000',
      demodulator_mode: :USB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb17: {
      start_freq: '18.068.000',
      target_freq: '18.168.000',
      demodulator_mode: :USB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb20: {
      start_freq: '14.000.000',
      target_freq: '14.350.000',
      demodulator_mode: :USB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb40: {
      start_freq: '7.000.000',
      target_freq: '7.300.000',
      demodulator_mode: :LSB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb80: {
      start_freq: '3.500.000',
      target_freq: '3.800.000',
      demodulator_mode: :LSB,
      bandwidth: '2.700',
      precision: 6
    },
    ssb160: {
      start_freq: '1.800.000',
      target_freq: '2.000.000',
      demodulator_mode: :LSB,
      bandwidth: '2.700',
      precision: 6
    },
    tempest: {
      start_freq: '400.000.000',
      target_freq: '430.000.000',
      demodulator_mode: :WFM,
      bandwidth: '200.000',
      precision: 4
    },
    wifi24: {
      start_freq: '2.400.000.000',
      target_freq: '2.500.000.000',
      demodulator_mode: :RAW,
      bandwidth: '20.000.000',
      precision: 7
    },
    zigbee: {
      start_freq: '2.405.000.000',
      target_freq: '2.485.000.000',
      demodulator_mode: :RAW,
      bandwidth: '2.000.000',
      precision: 7
    }
  }
rescue StandardError => e
  raise e
end

.scan_range(opts = {}) ⇒ Object

Supported Method Parameters

PWN::Plugins::GQRX.scan_range(

gqrx_sock: 'required - GQRX socket object returned from #connect method',
demodulator_mode: 'required - Demodulator mode',
bandwidth: 'required - Bandwidth',
start_freq: 'required - Starting frequency',
target_freq: 'required - Target frequency',
precision: 'required - Precision',
lock_freq_duration: 'optional - Lock frequency duration (defaults to 0.5)',
strength_lock: 'optional - Strength lock (defaults to -60.0)'

)



249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
# File 'lib/pwn/plugins/gqrx.rb', line 249

public_class_method def self.scan_range(opts = {})
  gqrx_sock = opts[:gqrx_sock]
  demodulator_mode = opts[:demodulator_mode]
  bandwidth = opts[:bandwidth]
  start_freq = opts[:start_freq]
  target_freq = opts[:target_freq]
  precision = opts[:precision]
  lock_freq_duration = opts[:lock_freq_duration]
  strength_lock = opts[:strength_lock]

  multiplier = 10**(precision - 1)
  prev_freq_hash = {
    demod_mode_n_passband: demodulator_mode,
    frequency: start_freq,
    bandwidth: bandwidth,
    audio_gain_db: 0.0,
    squelch: 0.0,
    rf_gain: 0.0,
    if_gain: 0.0,
    bb_gain: 0.0,
    strength: 0.0,
    strength_lock: strength_lock,
    lock_freq_duration: lock_freq_duration
  }
  if start_freq > target_freq
    start_freq.downto(target_freq) do |freq|
      next unless (freq % multiplier).zero?

      init_freq_hash = init_freq(
        gqrx_sock: gqrx_sock,
        freq: freq,
        demodulator_mode: demodulator_mode,
        bandwidth: bandwidth,
        lock_freq_duration: lock_freq_duration,
        strength_lock: strength_lock
      )

      current_strength = init_freq_hash[:strength]
      prev_strength = prev_freq_hash[:strength]
      prev_freq = prev_freq_hash[:frequency]

      approaching_detection = true if current_strength > prev_strength &&
                                      current_strength > strength_lock
      if approaching_detection && current_strength <= prev_strength
        puts "\n**** Found a signal ~ #{prev_freq} Hz ****"
        puts JSON.pretty_generate(prev_freq_hash)
        approaching_detection = false
      end

      prev_freq_hash = init_freq_hash
    end
  else
    freq = start_freq
    while freq <= target_freq
      init_freq_hash = init_freq(
        gqrx_sock: gqrx_sock,
        demodulator_mode: demodulator_mode,
        bandwidth: bandwidth,
        freq: freq,
        lock_freq_duration: lock_freq_duration,
        strength_lock: strength_lock
      )

      current_strength = init_freq_hash[:strength]
      prev_strength = prev_freq_hash[:strength]
      prev_freq = prev_freq_hash[:frequency]

      approaching_detection = true if current_strength > prev_strength &&
                                      current_strength > strength_lock
      if approaching_detection && current_strength < prev_strength
        puts "\n**** Discovered a signal ~ #{prev_freq} Hz ****"
        puts JSON.pretty_generate(prev_freq_hash)
        approaching_detection = false
      end

      prev_freq_hash = init_freq_hash

      freq += multiplier
    end
  end
end