[mythtvnz] MythTV problems after moving house & installing new Frontend/Backend server

[Stephen Worthington]

On Wed, 20 Jul 2016 09:27:10 +1200, you wrote:

>Hi,
>
>I'm having a few problems with a new Frontend/Backend server I 
>implemented after moving house. The old location had Terrestrial 
>Freeview, but the new location is Satellite Freeview only. I was having 
>some niggling problems with the old server, after a reboot Frontend 
>would take 20 to 30 minutes to appear after X started and it was running 
>low on hard disc space, so decided to implement a new server.
>The new server worked fine at the old house as a standalone, but now I 
>try to use at new location and integrate into my Home Theatre setup I 
>get two problems:-
>
>1. I get no reception on the TBS 6805 tuner card despite the MythTV 
>Channel Setup saying at least as good signal strength as at the old 
>house and was working fine at old house. When I insert my Satellite 
>Signal Meter (cheap $25 moving coil meter type) into the feeder, I get 
>good signal strength AND suddenly the TBS card picks up channels ???!!!! 
>Is this some kind of impedance matching issue that the meter is solving? 
>I have a replacement LNB I could try, but as it's a rented house I don't 
>want to fiddle with the dish unless I have to.

That sounds like a problem with your aerial connections.  The LNB
needs power and if there are splitters in the aerial, generally only
one port of the splitter is marked as "power pass through" or the
equivalent.  So something that provides power needs to be on that
port.  When you attached the signal meter, it may have been on that
port, so it gave the LNB the power it needs.  Splitters are small and
I have one where the marking is in tiny print, much smaller than the
other writing.  So it is easy to miss it.

The polarisation of the signal is also controlled via the power
supplied - lower voltage for vertical and higher for horizontal.

See here for a good page on LNBs:

http://www.satsig.net/lnb/explanation-description-lnb.htm

I have my TBS 5922 USB tuner attached to my "power passthrough"
connector, as it is externally powered by a wall wart and does that
job for me.  I do not know if your TBS 6805 will do it too, but I
would hope so.  If you leave your backend box on 24/7 it would be the
best choice.  A DVB-S/S2 capable TV might also work if it provided
power when left in standby.  If you have Sky, the Sky box will provide
power, but I do not know if it does that while in standby - I would
hope so.

It is also possible that the LNB at your new house has a different
local oscillator frequency.  The modern Sky dishes are all 10750 MHz,
but there are a couple of other frequencies that have been used.  And
on older dishes, the LO frequency can drift a little and you sometimes
need to adjust that setting a bit for best reception.