1.662 TX-ChannelSelect-CDB

The TX-ChannelSelect-CDB logical device controls some basic parameters of an encoder / modulator from a common channel database. The device complements the RX-ChannelSelect-CDB logical device which provides a similar function for receive chains.

TX-ChannelSelect-CDB is comparable to the TX-ChannelSelect device, but is intended for the use in a sat-nms NMS system. "CDB" in the driver name stands for "Central Data Base", underlining that all TX-ChannelSelect-CDB instances use one central satellite channel database located at the NMS server. The TX-ChannelSelect-CDB device shares this channel database with it's receive chain pendant.

Device window pages

The following table shows which device window pages are available with this individual device type. Tool-bar functions not mentioned here are described at the general description of device windows .

• --- The main control (channel select) page for the device.
• --- The channel database editor page.
• --- The fault page. There is one fault signal the device (optionally) monitors, this fault is reported as "TX Chain" fault.
• --- The device info page.
• --- The maintenance page. The configuration parameters from this page are described below.

Operation (channel select)

To configure the transmit chain for a certain satellite channel, simply select a satellite channel from the list. This commands the parameters

• tx frequency
• fec
• symbol rate
• dvb mode
• pilots
• roll-off
• modulation
• tx polarization

as stored with the channel definition. Please note, that the TX-ChannelSelect-CDB device neither controls the TX-ON state if the equipment nor the transmit power. The operator is responsible to switch off the transmission before applying a satellite channel data record and also to perform the line up procedure as specified.

Instead of selecting the satellite and channel you also may enter the transmit parameters at the frequency / pol / symbol rate / fec fields. The TX-Channelselect-CDB device forwards these settings to the ancillary devices.

Operation (database edit)

With the second page of the device window of the TX-ChannelSelect-CDB device channel definitions are edited, copied or deleted. All TX-ChannelSelect devices in a sat-nms NMS share one common channel database located at the NMS server. The VLC containing the TX-ChannelSelect-CDB device requires an online connection to the NMS central database in order to make any changes to the database. Selecting channels at this page or changing any channel parameters do not change the receiver settings.

• Change certain parameters of a channel:
  1. Select the channel to modify
  2. Edit the settings
  3. Click 'SAVE'Please note that if you change the channel name (composed of the satellite / channel id entries), this will store a new channel definition with the modified data, the old channel is kept unchanged in the database.The channel name may consist of letters (a-z, A-Z), digits, space characters and some punctuation characters (,.-_). All other characters are turned to underscore characters when the channel gets stored.
• Save the actual receive settings as a new channel:
  1. Click 'READ' to fill the fields from actual receive settings.
  2. Optionally complete the transmit parameters for the channel.
  3. Enter the desired satellite / channel name.
  4. Click 'SAVE'
• Delete a channel:
  1. Select the channel to delete
  2. Click 'DELETE'

Local database copy

sat-nms VLCs may be operated locally by connecting an M&C client directly to the VLC. This may be used as a backup operation mode in cases where the NMS server is down or unreachable. To uphold the TX-ChannelSelect-CDB functionality even in this backup case, the VLC maintains a local copy of the channel database. This copy is used if the CDB at the NMS is unreachable. You cannot edit the channels in this local backup copy, but you can apply stored channels to the IRD.

There are two ways to update the local copy of the channel database at the VLC:

1. At the "Database" page of the device window of a TX-ChannelSelect-CDB device click "VLC UPD". This requests the complete database contents from the NMS server and stores it locally.
2. Administrators may configure a VLC to update the local database copy in regular intervals. To make a VLC update it's local database copy automatically, add a line cdb.channels.syncInterval=#.# to the file vlc.properties and restart the VLC. '#.#' is the time interval in hours.

EBU DREAMS channel list import

The channel database is capable to import channel lists from the EBU DREAMS software. The DREAMS channel lists are distributed as two CSV tables, on for RX and one for TX. In the sat-nms channel database these lists get merged. EBU channels are marked "read-only" in the database, they only may be changed by importing a new EBU channel list.

To import a pair of EBU channel lists, click the "IMPORT" button at the "Database" page of the TX-ChannelSelect-CDB device's device screen. This opens a new window where the names of the files to import must be entered. The small buttons beside the file name entry fields open a file select dialog which lets you select the file names fom the directory.

After you have set the file names, click "READ". The software reads and parses the CSV files. It also matches corresponding RX and TX channels, because the sat-nms channel database stores only one entry for each channel containing both, the RX and TX parameters.

The software reports the number channels read from each file and the number of channels matched. Sometimes the numbers slightly differ, e.g. if the original channel names in the RX and TX lists are not really identical. You have to edit and repair the original files if you want to fix this.

If you are satisfied with the parsing result, click "IMPORT". This imports the channel definitions to the sat-nms database. All existing EBU channel definitions are deleted and replaced by the new ones. The user defined channels in the database remain unchanged by this.

Please note, that this procedure copies the EBU channels directly from the client PC to the NMS server, the TX-ChannelSelect-CDB device is not involved in this and does not recognize the new channels immediately. This happens with the next regular update of the channel list, max 5 minutes later.

Configuration parameters

At the maintenance page of the device window there are a couple of configuration parameters which must be set to interconnect the TX-ChannelSelect-CDB device with the transmit equipment.

Variables defined by this device driver