Frontend Startup. Category : Configuring MythTV. Navigation menu Personal tools Log in. Namespaces Page Discussion. Views Read View source View history. This page was last modified on 12 October , at This is a popup list; select the correct country. If your country is not present then select a country nearby and see what happens.
After making the selection press the left arrow key to go back to the Channel Scan page. If you forget to select your country then usually Australia is used as default, which may or may not be what you want.
Do NOT press Escape as this discards all entered values. For each video source the last 10 scans are saved for some time. With this option you can process and store the results of a previous scan again. This is extremely useful if a scan takes a long time and you want to see the results of different processing options, for example to see what happens when the "Complete scan data required" is unchecked or when a different region ID is selected.
This option is now available in MythTV version 32; in previous versions the option was present but it did not work. This is the option that is recommended for a rescan. Channels do disappear and new channels appear from time to time but the multiplexes usually change less frequent. After this is selected, press the right arrow key to get the menu page in which the multiplex can be selected.
The first field can be used to select the multiplex with a popup menu. Default is the first multiplex. The next field is "Ignore signal timeout". This can usually be left unchecked.
If it is needed then it might be a good idea to increase the signal timeout value for that capture card. The last field is "Search new Transports". If this option is checked then new transports will be added to the video source when the NIT network information table in the selected multiplex does have this information. This page shows the scanning progress. This is what is called the number of "probable channels" which includes all channels that are later filtered out, such as incomplete channels and data channels, depending on the options given.
When the scanning is ready there comes a popup box that, if the scanning is successful, says something like Found 33 new DVB channels. Select Insert All and then all channels are stored in the database. The possible choices in this popup box does depend on the success of the scan and if the channels found are already in the database.
As an example, let us redo the same scan but with different scan parameters. The DVB-T2 source scanned in the example has 33 TV channels of which 5 are free-to-air not encrypted and 28 are encrypted. Selecting the scan option Unencrypted only and doing a new scan gives the following results:. The 28 encrypted channels are now filtered out by the "Unencrypted only" option. These channels are now classified as "off-air channels", which are the channels in the database that are not found in the scan.
Selecting "Delete All" will indeed delete these channels. Be very careful with deleting channels as they cannot easily be undeleted. When in doubt, check the scan parameters and scan again to make sure that the channels are really gone.
In real life, if you rescan once or twice a year, only a few channels are gone and a few new channels are found, so a large number of off-air channels is usually an indication something is wrong. The 5 free-to-air channels are found in the database and are classified as "old" channels.
Selecting "Update All" will update the database with the values from the scan and "Ignore All" does not do this. There is a subtle difference between updating and ignoring but generally the "Update All" is the recommended choice.
Saving is essential otherwise the channels are not stored in the database. To get complete coverage TV signals are broadcast on a number of transmitters spread over the country. Transmitters of adjacent regions use different frequencies to avoid interference. Depending on where you live it is thus possible to receive exactly the same transport stream multiplex on two different frequencies.
If this happens then mythtv-setup selects the transport with the best signal and discards the other one. One Full Scan is expected to give the correct channel list. If the option Remove Duplicates is unchecked or when using an older version of MythTV then mythtv-setup just stores all multiplexes and all received channels which means that the channel list will have duplicates.
In that case proceed with the procedure described below. The best way is to figure out from other sources which transmitter and which frequencies are to be used in your region. Then delete all the transports that you do not want to receive.
This can be done with the Transport Editor; a transport can be deleted by pressing the key "D". Then, back in the Channel Scan page, delete all channels and do a Full scan of all existing transports. This will create the correct channel list. Once the list of transports is correct it is advised to do only Full scan of all existing transports whenever a rescan is needed to avoid the duplicate transports appearing again.
However, when transports move to other frequencies then the Full Scan must be done. It is not possible to select a scanning range so that the unwanted transports are avoided, such as is possible with the ATSC scanner. It is also possible to manually add a transport with the Transport Editor and then do a scan of only that transport. This is only practical when there are not too many transports of interest.
These TV's then do get all the channel information from only the multiplex on that frequency, which then takes only about 20 seconds. This is something that MythTV does not yet support; MythTV only adds channels from multiplexes that it has actually received. There are also TV's that do something like a "Full Scan" but then with, optionally, frequency steps of 1 MHz or less instead of the channel bandwidth of 8 MHz.
This is not implemented in MythTV. The modulation type for the initial frequency is not stored in the video source; the modulation type has to be given the first time a "Full Scan Tuned " is done. After a successful scan the modulation type does not need to be entered ever again because it is stored in the database for each multiplex. The initial frequency stored in the video source is sufficient to retrieve all tuning data for new scans.
These cards appear as two devices in Linux and consequently also in MythTV. Check the list of possible delivery systems to make sure the correct frontend is selected. In that case it is possible to configure both frontend0 and frontend1 and both devices can be used, although not at the same time. These cards are really one device with two inputs of which only one can be used at a given moment.
MythTV does actually support this in the scheduler. If you card is capable of DVB-S2 then this is the default. Only old capture cards support only DVB-S. The other possible values are:. This is the choice when the LNB low noise block of the satellite is directly connected to the input of the card.
With one card input it is then possible to use one satellite dish with four LNBs, each pointing to a different satellite, or to use four different satellite dishes each with one LNB. Only one LNB can be received at a time. The following screen shots show how to configure the LNB type to Universal Europe which is also the default. There are a number of preset configurations defined and it is also possible to set the values for your particular system if the presets do not fit your hardware.
The only parameter specified here, in addition to giving this video source a name, is the initial scanning frequency. The frequency used in this example, kHz Other frequencies can be found on www. Another source of information is linuxtv. As this is a git archive the information can be easily downloaded.
Only the initial frequency is stored in the video source; the other modulation parameters have to be given the first time a "Full Scan Tuned " is done. After a successful scan the modulation parameters do not need to be entered ever again because they are stored in the database for each multiplex. The initial frequency should select a transport stream that carries the information about all other transport streams in the network.
On some networks this information is present in every transport stream but that is not always the case. For a number of satellites default values for the initial scan frequency plus tuning parameters can be selected. It is possible to create complex configuration with switches after switches, some switch outputs connected to an LNB, another switch output connected to a rotor etc etc.
The good news is that MythTV does support about any configuration. However, the configuration order is not entirely obvious. As an example, all configuration steps for a four-LNB satellite system are given here.
This is done by creating four almost identical capture card entries that all use the same physical capture card. Each capture card entry is then connected to one of the four LNBs. It is essential that for all four capture card entries the option Open DVB card on demand is checked in order to be able to change from one LNB to another. In mythtv-setup create the first capture card, configure a DiSEqC switch and change the number of ports to For the fourth LNB etc etc. Now it is possible to do a channel scan for each satellite in exactly the same way as if there is only one LNB directly connected to the capture card input.
This is a limitation of the current implementation and this may be resolved in the future. In this example configuration this is checked for the first satellite and not for the others but this is arbitrary; it can be any of the four but it can be only one. In the video source the "Channel frequency table" can be selected. There are entries for various countries but for the USA there are four entries specifying both the USA and a delivery system: "us-bcast", "us-cable", "us-cable-hrc" and "us-cable-irc".
The Channel frequency table specified here is the default value for the Channel frequency table selection in the Scan Type "Full Scan" option. Now, pressing the right arrow key shows three fields with configuration data. After the parameters have been selected press the left arrow key to go back to the Channel Scan page. The Full Scan takes a lot of time because it tries all possible frequencies but it is the only way to find all channels if you start with a clean slate.
If you know you for a fact that you should be getting some channels, but mythtv's scanning isn't working - you can try to fix it by doing these two things:. For at least one user, the above set of steps solved the problem of getting 0 channels reported. The hdhomerun-config may be required for the scanner to work properly? You may have a firewall in the middle blocking traffic. If so, an easy solution is adding a firewall rule that permits all traffic to and from the HDHR.
It is convenient or maybe required for your OS flavor when using a GUI to edit the rules to store this rule in an external file. However, with the latest firmware it is also possible to configure it statically.
To do this, configure your local interface with a static IP address in the range of No need to configure routes, the HDHR's will not be accessible to devices on your existing network, but your backend should have no problem seeing them. Alternatively add the following lines to your interfaces file 'ipv4ll' is a relatively new option, easier than using 'static' :. Since UDP is connectionless, it does not retry if a packet is lost.
This can cause a problem with hubs, especially with multiple HD video streams and other traffic. Any collision on the network generally results in part of the video stream being lost. This shows up as random blocks in the video being corrupt, generally with colors that stand out against the video. Switches resolve this problem since they break up the network into more collision domains, although this problem will still appear if then network becomes fully saturated with traffic.
There may be an issue with in addressing the second tuner of the HDHomeRun, which will result in existing recordings terminating aburptly when the other tuner is accessed by MythTV. It would be worth noting that, and if there are any special mythtv settings to make surrounding the stream. Bs talk , 10 February UTC. Jump to: navigation , search. Navigation menu Personal tools Log in. Namespaces Page Discussion.
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