dumpvdl2 --help
dumpvdl2 2.6.0 (libacars 2.2.1)
Usage:
RTL-SDR receiver:
dumpvdl2 [output_options] --rtlsdr <device_id> [rtlsdr_options] [<freq_1> [<
freq_2> [...]]]
Read I/Q samples from a file (use "-" to read from standard input):
dumpvdl2 [output_options] --iq-file <input_file> [file_options] [<freq_1> [<
freq_2> [...]]]
General options:
--help Displays this text
--version Displays program version number
common options:
--max-ppm <max_ppm> Set maximum allowable absolute PPM deviation for valid messages (default: 0 == unlimited) <freq_1> [<freq_2> [...]] VDL2 channel frequencies If channel frequencies are omitted, VDL2 Common Signalling Channel (136975000 Hz) will be used as default.
rtlsdr_options:
--rtlsdr <device_id> Use RTL device with specified ID or serial number (default: ID=0)
--gain <gain> Set gain (decibels)
--correction <correction> Set freq correction (ppm)
--centerfreq <center_frequency> Set center frequency (default: auto)
--oversample <oversample_rate> Oversampling factor (sampling rate will be set to 105000 * oversample)
--bias <bias> Enable(1) or Disable(0) bias tee (default: 0)
file_options:
--iq-file <input_file> Read I/Q samples from a file (use "-" to read from standard input)
--centerfreq <center_frequency> Center frequency of the input data, (default: 0)
--oversample <oversample_rate> Oversampling factor (sampling rate will be set to 105000 * oversample) (sampling rate will be set to 10
5000 * oversample_rate) Default: 10
--sample-format <sample_format> Input sample format. Supported f
ormats: U8 8-bit unsigned (eg. recorded with rtl_sdr) (default) S16LE 16-bit signed, little-endian (eg. recorded with miri_sdr)
Output options:
--output <output_specifier> Output specification (default: decoded:text:file:path=-) (See "--output help" for details)
--output-queue-hwm <integer> High water mark value for output
queues (0 = no limit) (default: 1000 messages, not applicable when using --iq-file or --raw-frames-file)
--decode-fragments Decode higher level protocols in fragmented packets
--gs-file <file> Read ground station info from <file> (MultiPSK format)
--addrinfo terse|normal|verbose Aircraft/ground station info verbosity level (default: normal)
--station-id <name> Receiver site identifier Maximum length: 255 characters
--msg-filter <filter_spec> Output only a specified subset of messages (default: all) (See "--msg-filter help" for details)
Text output formatting options:
--utc Use UTC timestamps in output and file names
--milliseconds Print milliseconds in timestamps
--raw-frames Print raw AVLC frame as hex
--dump-asn1 Print full ASN.1 structure of CM and CPDLC messages
--extended-header Print additional fields in message header
--prettify-xml Pretty-print XML payloads in ACARS and MIAM CORE PDUs
--prettify-json Pretty-print JSON payloads in OHMA messages
Frequencies might be specified in Hz (as integer numbers) or in kHz, MHz, GHz (as integer or floating-point numbers followed by any of the following suffixes: k, K, m, M, g, G).
Examples: 136975000, 136975k, 136.975M, 0.136975G
dumpvdl2 --output help
dumpvdl2 2.6.0 (libacars 2.2.1)
<output_specifier> is a parameter of the --output option. It has the following syntax:
<what_to_output>:<output_format>:<output_type>:<output_parameters>
where:
<what_to_output> specifies what data should be sent to the output:
decoded Output decoded frames
raw Output undecoded AVLC frame as raw bytes
<output_format> specifies how the output should be formatted:
text Human readable text
pp_acars One-line ACARS format accepted by Planeplotter via UDP
json Javascript object notation
<output_type> specifies the type of the output:
file Output to a file
udp Output to a remote host via UDP
<output_parameters> - specifies detailed output options with a syntax of: pa
ram1=value1,param2=value2,...
Parameters for output type 'file':
path Path to the output file (required)
rotate How often to start a new file: Accepted values: daily, hourly
Parameters for output type 'udp':
address Destination host name or IP address (required)
port Destination UDP port (required)
dumpvdl2 --rtlsdr 0 --gain 40 --centerfreq 136975000
136975000
Las frecuencias para europa que se recomiendan son: 136725000 136775000 136825000 136875000 136975000
dumpvdl2 2.6.0 (libacars 2.2.1)
Sampling rate set to 1050000 sps
Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001
Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Exact sample rate is: 1050000.026077 Hz
[R82XX] PLL not locked!
Center frequency set to 136975000 Hz
Bandwidth set to 21000 Hz
Device #0: gain set to 40.20 dB
Device 0 bias tee set to 0
Device 0 started
Allocating 15 zero-copy buffers
[2026-05-10 12:13:30 CEST] [136.975] [-33.5/-12.2 dBFS] [-21.3 dB] [-2.1 ppm]
347247 (Aircraft, Airborne) -> 1096DA (Ground station): Command
AVLC type: I sseq: 3 rseq: 4 poll: 0
X.25 Data: grp: 11 chan: 255 sseq: 1 rseq: 2 more: 0
X.25 reasm status: skipped
X.233 CLNP Data (compressed header):
LRef: 0x42 Prio: 11 Flags: 0xf6
Lifetime: 20.0 sec
PDU Id: 0x102
X.224 COTP Data:
dst_ref: 0xda8a
sseq: 2 req_of_ack: 0 EoT: 1
COTP reasm status: skipped
ATN checksum: 51 79 63 d5
CPDLC Downlink Message:
Header:
Msg ID: 2
Msg Ref: 3
Timestamp: 2026-05-10 10:13:28
Logical ACK: required
Message data:
WILCO
