Dvbv5scan Initial File
| Issue | Likely Cause | Solution |
|-------|--------------|----------|
| No lock on any frequency | Wrong initial file (wrong region/delivery system) | Obtain correct initial file |
| Only partial services found | NIT missing other transponders | Use -f to force full initial list |
| AUTO parameters fail | Old or buggy demodulator firmware | Specify parameters explicitly |
| Permission errors | User not in video group | sudo usermod -a -G video $USER |
# Scan a single transponder and generate initial file
dvbv5-scan -I dvbv5 -o initial.conf -O vdr <adapter>
Most useful feature: The -O vdr (output format) flag creates initial files compatible with both dvbv5-scan and VDR, making it the best interoperability format for multi-application use.
The dvbv5-scan initial file is a critical configuration file used by the dvbv5-scan tool to locate digital TV services. It acts as a starting point, listing known frequencies and physical parameters for transponders in a specific region or for a specific satellite. Purpose and Functionality
The primary role of the initial file is to provide the scanner with enough data to "lock" onto a signal. Once a signal is found, the dvbv5-scan tool can often retrieve the Network Information Table (NIT) directly from the stream, which contains details about other available transponders, making the initial file a "seed" for a broader discovery process.
Format Support: It primarily uses the modern DVBv5 format, which supports all current digital TV standards (DVB-T/T2, DVB-S/S2, DVB-C, ATSC, and ISDB-T). dvbv5scan initial file
Legacy Compatibility: It remains backward compatible with older DVBv3 formats used by legacy dvb-apps. Performance and Reliability
Using an initial file significantly speeds up the scanning process compared to a "blind scan" of all possible frequencies. However, its effectiveness depends entirely on the accuracy of the data provided.
Data Accuracy: A common criticism is that the default initial files provided in standard repositories (like dtv-scan-tables) are often outdated because local broadcast parameters change frequently.
Maintenance: These files are community-maintained; if your local transmitter has updated its frequencies and the file hasn't been refreshed, the scan will fail to find any channels. Acquisition and Customization | Issue | Likely Cause | Solution |
Users typically find these files in the dtv-scan-tables repository, which is installed by default on many Linux distributions (e.g., in /usr/share/dvbv5/ or /usr/share/dvb/).
Manual Creation: If a file for your specific region is missing or incorrect, you can manually create one or use third-party tools like w_scan to generate a fresh DVBv5-compliant initial file.
Key Parameters: An initial file must include essential keys like FREQUENCY, MODULATION, BANDWIDTH_HZ, and DELIVERY_SYSTEM to be functional. ISDB-T scanning with tsscan gives no results #578 - GitHub
Once you have a working initial file, you can script channel scans via cron. For example, to rescan every Sunday at 3 AM: # Scan a single transponder and generate initial
0 3 * * 0 /usr/bin/dvbv5scan -a 0 -f 0 -I /etc/dvb/initial.ini -o /home/htpc/channels.conf > /var/log/dvb_scan.log 2>&1
This is especially useful for IPTV gateways or home media servers where channel frequencies or multiplex parameters change occasionally.
For terrestrial TV (antenna), you must define the center frequency and bandwidth. Below is a standard DVB-T initial file for a region using UHF frequencies with 8MHz bandwidth.
File: dvbt-initial.conf
# Delivery system definition
DELIVERY_SYSTEM = DVBT