[mythtv-users] No live tv and not recording

Wed Mar 14 23:34:04 UTC 2018

On Wed, 14 Mar 2018 20:18:28 +0100, you wrote:

>Le mercredi 14 mars 2018, 19:23:57 CET Klaus Becker a écrit :
>> Le jeudi 15 mars 2018, 02:17:36 CET Stephen Worthington a écrit :
>> > Yes, that is a Universal LNB, with two local oscillators.  So the low
>> > and high frequencies are what you need.  The switch frequency is not
>> > defined by the LNB - it has to take into account the capabilities of
>> > your DVB-S2 cards and the highest and lowest frequencies you want to
>> > receive from your satellites.  The DVB-S2 cards will have a
>> > specification for the frequency range they support.
>> > 
>> > The way it all works is that the frequency of the satellite
>> > transmitter (TF) gets mixed in the LNB with the local oscillator
>> > frequency (LOF), and that produces signals at frequencies of TF+LOF
>> > and TF-LOF on the aerial cable down from the LNB.  The TF+LOF signal
>> > is a very high frequency that is probably too high to even propagate
>> > well down the aerial cable, and is so high that your DVB-S2 card will
>> > not see it either.  The card may have a filter circuit to block it if
>> > necessary.  The TF-LOF signal is the one the card needs to be able to
>> > receive.  My TBS 6909 DVB-S2 card can receive 950 - 2150 MHz, and most
>> > consumer style DVB-S2 cards will have a very similar frequency range.
>> > So, using those numbers, you need to have TF-LOF in that range, so
>> > using your low LOF frequency of 9750 MHz, the DVB-S2 card will be able
>> > to receive from transmitters in the range 10,700 MHz - 11,900 MHz.
>> > Using your high LOF frequency of 10600 MHz, the card will be able to
>> > receive from transmitters in the range 11,550 MHz - 12,750 MHz.  There
>> > is an overlap in the middle, so transmitters in the range 11,550 MHz -
>> > 11,900 MHz are able to be received using either the low LOF or the
>> > high LOF.  So the switch frequency where reception changes from using
>> > the low LOF to the high LOF needs to be set in that overlap range - I
>> > would suggest having it in the middle at say 11,725 MHz.  The switch
>> > frequency is used by mythbackend to decide whether to tell the DVB-S2
>> > card to switch on or off the 22 kHz tone that tells the LNB to switch
>> > to the high LOF.
>> > 
>> > The full frequency range you will be able to receive from is 10,700
>> > MHz - 12,750 MHz, so I hope that covers everything you want to receive
>> > from your satellites.
>> 
>> ....
>> 
>> Hi Stephen,
>> 
>> Thanks for all these explanations !
>> 
>> I tried again with
>> 
>> LOF- =  		 9750 MHz
>> LOF+ = 		10600 MHz
>> LOF Switch = 	11725 Mhz
>> 
>> No signal for scanning!
>> 
>> And still the message "DVBChan[1](/dev/dvb/adapter0/frontend0): Your
>> frequency setting (114000) is out of range. (min/max:925000/2175000)"
>> 
>> 
>> But the LOF Switch (11725 Mhz) is not in the middle oh LOF- (9750 Mhz) and
>> LOV + (10600 Mhz).
>> 
>> Did I understand you right ?
>> 
>> LOF Switch does'nt depend on LOF- and LOF+ but on the capabilty of the card
>> ?
>> 
>> Iif so, the only problem I have seems to be the above error message about
>> the frequency setting.
>> 
>> I have no splitting. My Optex antenna has 2 LNBs but acually I use only one.
>> 
>> Bye
>> 
>> Klaus
>
>I tried again: mythtv-setup does not keep the LOF Switch setting I give it, it 
>always keeps 1500 Mhz I gave it before.
>
>And "DVBChan[1](/dev/dvb/adapter0/frontend0): Your frequency setting (114000) 
>is out of range. (min/max:925000/2175000)"
>
>Klaus

That will be the problem then - there have been other reports that
when you edit the LNB settings in v29, there seems to be a bug and the
settings are sometimes not saved.  I think there was supposed to be a
bug fix for that coming through, so it would pay to update to the
latest version of v29 to see if the fix is there yet.  Are you using
the PPA to get the latest versions of MythTV, or just the standard
packages from the Debian repositories?  If you are not using the PPA,
you will need to install that and then update to the latest PPA
version.

If you are unable to get mythtv-setup to save the LNB settings
properly, it is possible to alter them using direct SQL commands.
There is no danger in directly accessing the database just using
"select" commands to read its data.  The only danger comes when you
make changes to it, using the "update" command.  So if you are in any
doubt, do not do "update" commands until you have posted the results
of the "select" commands for us to check them.

I am posting examples from my test MythTV box, which currently has one
DVB-S2 card configured, a TBS 5922.

Before attempting to alter the database, shut down mythbackend.  Then
to get access to command line SQL commands, do this:

sudo mysql

This is the result I get from that command:

stephen at lith:~$ sudo mysql
[sudo] password for stephen:
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 159
Server version: 10.0.34-MariaDB-0ubuntu0.16.04.1 Ubuntu 16.04

Type 'help;' or '\h' for help. Type '\c' to clear the current input
statement.

Note that I am using MariaDB for my database - you will likely have
real MySQL, so the incidental text and messages will be a little
different.  The results should be the same format as mine.

Then do the command:

use mythconverg;

Result:

MariaDB [(none)]> use mythconverg;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed

Command:

select distinct diseqcid from capturecard where diseqcid!=0;

Result:

MariaDB [mythconverg]> select distinct diseqcid from capturecard where
diseqcid!=0;
+----------+
| diseqcid |
+----------+
|       12 |
+----------+
1 row in set (0.00 sec)

You can see that in the capturecard table, which sets up the tuners,
there is only one value other than 0 in the diseqcid field.  That
means I have only one set of LNB settings being used in my database,
with an ID of 12.

Command:

select * from diseqc_tree\G

Result:

MariaDB [mythconverg]> select * from diseqc_tree\G
*************************** 1. row ***************************
       diseqcid: 2
       parentid: NULL
        ordinal: 0
           type: lnb
        subtype: voltage
    description: LNB
   switch_ports: 0
 rotor_hi_speed: 0
 rotor_lo_speed: 0
rotor_positions:
 lnb_lof_switch: 0
     lnb_lof_hi: 14350000
     lnb_lof_lo: 10750000
     cmd_repeat: 1
    lnb_pol_inv: 0
        address: 0
   scr_userband: 0
  scr_frequency: 1400
        scr_pin: -1
*************************** 2. row ***************************
       diseqcid: 12
       parentid: NULL
        ordinal: 0
           type: lnb
        subtype: voltage
    description: Sky 10750 LNB
   switch_ports: 0
 rotor_hi_speed: 0
 rotor_lo_speed: 0
rotor_positions:
 lnb_lof_switch: 0
     lnb_lof_hi: 0
     lnb_lof_lo: 10750000
     cmd_repeat: 1
    lnb_pol_inv: 0
        address: 0
   scr_userband: 0
  scr_frequency: 1400
        scr_pin: -1
2 rows in set (0.00 sec)

Here you can see that my diseqc_tree table has two entries, with IDs 2
and 12.  Since ID 2 was not listed in the prior query, it is unused.
The row with diseqcid=12 is the one we need to alter, containing the
settings for the LNB.  Your database may have several unused LNB
settings like ID 2 if you have had several goes at setting up the
tuners.  In the row of the table with the LNB settings that are being
used, you should see the lnb_lof_switch field with its incorrect value
of 1500.  To update that, do this command, but replace the 12 with the
diseqcid of the correct row in your diseqc_tree table:

update diseqc_tree set lnb_lof_switch=11725000 where diseqcid=12;

Result:

MariaDB [mythconverg]> update diseqc_tree set lnb_lof_switch=11725000
where diseqcid=12;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

And now display the row that was changed to see the results of the
change.

Command:

select * from diseqc_tree where diseqcid=12\G

Result:

MariaDB [mythconverg]> select * from diseqc_tree where diseqcid=12\G
*************************** 1. row ***************************
       diseqcid: 12
       parentid: NULL
        ordinal: 0
           type: lnb
        subtype: voltage
    description: Sky 10750 LNB
   switch_ports: 0
 rotor_hi_speed: 0
 rotor_lo_speed: 0
rotor_positions:
 lnb_lof_switch: 11725000
     lnb_lof_hi: 0
     lnb_lof_lo: 10750000
     cmd_repeat: 1
    lnb_pol_inv: 0
        address: 0
   scr_userband: 0
  scr_frequency: 1400
        scr_pin: -1
1 row in set (0.00 sec)

Command:

quit

Result:

MariaDB [mythconverg]> quit
Bye

Now you can restart mythbackend and see if it works.