<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
<title></title>
</head>
<body bgcolor="#ffffff" text="#000000">
<br>
Hi Johan;<br>
<br>
Looks like you're on the right track - but you might need some slight
tweeks to get this to work with your LNB.<br>
<br>
0) Tone, Voltage, Band, Polarity<br>
<br>
Band == Tone<br>
Polarity == Voltage<br>
<br>
The receiver signals the LNB which Band and Polarity to use by setting
the Tone and Voltage on the line.<br>
<br>
No 22kHz = Low Band<br>
22 kHz = High Band<br>
<br>
18V = horizontal<br>
13V = vertical (I always get those reversed so you might like to check
them)<br>
<br>
So where ever you have a chart with Band and Pol you can think of it
in terms of what Tone and Voltage you need to send to select them.<br>
<br>
<br>
Right - on with the show, lets start from the beginning.<br>
<br>
1) Universal LNBs<br>
<br>
Universal LNBs are used primarily in Europe to solve a particular
problem.... Too many channels =)<br>
A standard LNB has an offset of something like 11300 and can tune into
signals in the 12.25GHz to 12.75GHz<br>
<br>
The problem in Europe is that this isn't enough of a band for all the
channels. So they came up with a second band and used Universal LNBs
which you can tell which band you want to tune to.<br>
Here are some example specs form a Universal LNB.<br>
<br>
<font color="Blue"><b>Input</b> <br>
Low Band: 10.7 ~ 11.7 GHz <br>
High Band: 11.7 ~ 12.75 GHz <br>
L.O. Frequency <br>
Low Band: 9.75 GHz <br>
High Band: 10.6 GHz </font><br>
<br>
So you can see that if the Frequency is lower then 11.7 GHz then you
need the low band and if it's higher thatn 11.7GHz then you're in the
high band.<br>
<br>
<br>
The reason I'm explaining this is because ALL channels you're going to
be able to pick up in this part of the world are higher than 11.7GHz
and therefore in the high band.<br>
As above, to select the high band you need to send the LNB a 22kHz
tone. So you essentially want to send this always.<br>
<br>
I've essentially hardcoded tone on some LNBs in the past by configuring
them with a tiny low band and a huge high band, but lets only worry
about that if it becomes a problem.<br>
<br>
<br>
2) Dual throat Universal LNBs<br>
<br>
So you have one of these where you use DiSEqC switching to choose which
of the throats to listen to.<br>
This is subtlly different to the system which I have, but it makes it
easier for you. All you really need is the following setup<br>
<br>
<br>
<tt>------Switch (DiSEqC)--------Universal LNB A<br>
|____Universal LNB B<br>
<br>
</tt>You don't need to do tone switching because you always need the
tone on. You also don't need to do voltage switching because your
channel selection will take care of that. So you really only need to
get that DiSEqC switch sorted. There are only two DiSEqC settings on
MythTV, these are 'Committed' and 'Uncommited' which correspond to
DiSEqC 1.0 and 1.1. DiSEqC 2.0 which you have is based on one of the
earlier standards but incorporates the ability to interrogate the
switch to see which way it's been switched to.<tt> </tt> So even
though Myth doesn't have specific 2.0 support, it might still be
backward compatible. So you're going to need to try both settings. <br>
<br>
<br>
<br>
3) Questions.<br>
<br>
<pre wrap="">>1: Where in the logs can I find what kind of decision Mythtv made on
>Diseqc, Tone and Voltage. This way I can correlate my setting with
>what I actually need. Now it's just trail and error, and don't like
>that.
Probably nowhere as it's not logged by default =). Restart the backend with "-verbose channel" and you should see these sorts of things.
>2: Can I change the tone setting in dvbtune? Then I can check if this
>works with my LNB (=Diseqc 2.0) or it's just a fluke it's working with
>dvbtune. I can't find it in any manual/synax I found on the net.
You can. I use --tone
>3: In your example, you select select as LNB "Universal" (10600) for
>SatA-Tone. How can this work if you already took care of the
>tone/voltages ?
of the 6 LNBs I have on my system only one of them is a Universal. I use them on the switching matrix so that I can have control over the Tone setting. I have found the Tone-Switch within Myth to be a bit unreliable.
If I want tone sent to an LNB (or to my switch to switch to that LNB) then I set it up as a Universal with a low band of 0-0.001GHz (ie tiny) and a high band of 0.001GHz to 20GHz (ie the whole band). This way when Myth is looking at which band it needs to select, it's always going to be High Band, and it will set tone. Similarly I can reverse these and get an LNB which will never have tone sent to it.
It's a bit of a hack but it works better for me than the MythTV tone switch.
Hope this helps. Let us know how you get on. And you're not kidding about there not being that much info out there on this!!!
Dean
</pre>
<br>
<br>
<br>
Johan Schuld wrote:
<blockquote
cite="mid:51d84c760806220532u1235ec8bk138b46a78cd1d25b@mail.gmail.com"
type="cite">
<pre wrap="">Hi Dean.
Let me start with apologising with probably a very confusing reply.
Thanks for the link. I've had a look and came up with the following.
(combined with Craigs suggestion). The LNB I have uses DiSEqC 2.0 I'm
not sure how to select the difference between 1 and 2, but I just
chose "DiSEqC" in the switch setup.
When looking at the datasheet, in the middle is a little table with
the DiSEqC command vs. Polarity, Band and Sat selection. It does not
mention Voltage and Frequency at all, maybe this LNB does not use that
at all? or am I talking rubbish. Mind you, with dvbtune I've got
success, so MythTV should be able to have success too then right..
So what I need to end up with is the following (I used the example on
your page as a guide)
For Freeview:
DiSEqC A - 22Khz - 18V (LNB1=D1, High Band, Horizontal Polarisation
For D2 (BVN)
DiSEqC B - 22Khz - 13V (LNB2=D2, High Band, Vertical Polarisation)
So I made in my setup
- DiSEqC Switch 2x (A and B)
- Tone Switch D1
- LNB-No Tone (not used)
- LNB-Tone-D1-High (this is Freeview)
- Tone Switch D2
- Unconnected
- Unconnected
Now a bit tricky what kind of LNB I select. As I've "immitated" the
LNB switching with the above structure I figured my best choice would
be a Custom/Legacy(Fixed) on 10600Mhz. (I've tried others too). Theory
being that the tone/voltage selection is done by now.
So up to input connections. I choose the right "tree" ("Port 1 Tone
Switch D1" and then "Port 2 LNB-Tone-D1-High'). I select my video
source (DVB-S) and "scan for channels" Now my theory is getting
already shaky by having a horizontal/vertical selection here). Entered
the freeview frequencies and no luck (probably of course)
So I'm still confused now. I am aware that I'm probably doing
something basic wrong. This is what I like to do now.
1: Where in the logs can I find what kind of decision Mythtv made on
Diseqc, Tone and Voltage. This way I can correlate my setting with
what I actually need. Now it's just trail and error, and don't like
that.
2: Can I change the tone setting in dvbtune? Then I can check if this
works with my LNB (=Diseqc 2.0) or it's just a fluke it's working with
dvbtune. I can't find it in any manual/synax I found on the net.
3: In your example, you select select as LNB "Universal" (10600) for
SatA-Tone. How can this work if you already took care of the
tone/voltages ?
Sorry if this gets a bit tool detailed/ off topic for the list. I've
spent quite some time searching the net or docs or examples but there
is really not much on this stuff (that I can find).
</pre>
<blockquote type="cite">
<pre wrap="">Hi Johan.
</pre>
</blockquote>
<pre wrap=""><!---->
</pre>
<blockquote type="cite">
<pre wrap="">This is 'similar' to my setup.
I wrote a HowTo a while ago on getting a multi LNB DiSEqC switch to work
</pre>
</blockquote>
<pre wrap=""><!---->
</pre>
<blockquote type="cite">
<pre wrap="">Have a read
<a class="moz-txt-link-freetext" href="http://www.mythtv.org/wiki/index.php/MultiLNB_Switch_Setup">http://www.mythtv.org/wiki/index.php/MultiLNB_Switch_Setup</a>. Compare
the "Port Layout" section on my page with the table in the PDF from the
site you linked to. If it doesn't fix your problems then feel free to
get back to me (either on or off list) and we'll step through the
settings and see whats up.<br>
</pre>
</blockquote>
<pre wrap=""><!---->
</pre>
<blockquote type="cite">
<pre wrap="">My switch is DiSEqC 1.0 though and I havn't played with any 2.0 stuff
under MythTV.; We'll give it a crack though
</pre>
</blockquote>
<pre wrap=""><!---->
</pre>
<blockquote type="cite">
<pre wrap="">Dean
</pre>
</blockquote>
<pre wrap=""><!---->
_______________________________________________
mythtvnz mailing list
<a class="moz-txt-link-abbreviated" href="mailto:mythtvnz@lists.linuxnut.co.nz">mythtvnz@lists.linuxnut.co.nz</a>
<a class="moz-txt-link-freetext" href="http://lists.ourshack.com/mailman/listinfo/mythtvnz">http://lists.ourshack.com/mailman/listinfo/mythtvnz</a>
Archives <a class="moz-txt-link-freetext" href="http://www.gossamer-threads.com/lists/mythtv/mythtvnz/">http://www.gossamer-threads.com/lists/mythtv/mythtvnz/</a>
</pre>
</blockquote>
<br>
</body>
</html>