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<H2><A NAME="s5">5. Base setup</A></H2>
<H2><A NAME="ss5.1">5.1 First: mounting</A>
</H2>
<P>The first thing we have to do is to mount our parabolic antenna;
<P>After we need to pointing it out (searching right degrees from some magazine):
degrees are always intended from south to east or to west for horizontal one
and from ground to satellite line for vertical one. Classical pointing tools
is the compass.
<H2><A NAME="ss5.2">5.2 Calibrating</A>
</H2>
<P>How can we see if we are right oriented?
<P>After decided a right range of angles, we have to adjust it measuring power
level. For such a thing we can
<P>
<OL>
<LI>Use for example an analog receiver (which is compatible with digital converter)
and start to search right degree: when we see some imagine we'll get it. I
suggest to use analog converter cause, maybe, you have one (from precedent
installation) and cause it is more simple to calibrate it than digital one.</LI>
<LI>Use a power meter (about 20US$) with sequential lights: at full
signal all lights turn up.</LI>
</OL>
<H2><A NAME="ss5.3">5.3 Double Feed</A>
</H2>
<P>You can also install a double feed system (some vendors sell a complete
kit with standard distance to receive, for example, Astra (19.2 SE) with Eutelsat
(16 SE) or with HotBird (13 SE).
<P>For mounting it you have to consider, in addition, that satellite is at
the opposite side of the converter, like in figure:
<P>
<PRE>
SAT1 SAT2
\ /
\ /
\ C1 C2 /
\ \ \ / / /
\ \ / \ / /
\____\ /___\ /_____/
Top View
C1 receives from SAT2
C2 receives from SAT1
</PRE>
<P>Also, with 2 focus, you would use a diseq.
<H2><A NAME="ss5.4">5.4 Data-link level adjusting</A>
</H2>
<P>Once we got analog signal we have to adjust our receiver to right frequency,
PID, speed rate and so on.
<P>I report here an example of configuration, for EON (EuropeOnLine), transponder
114 on Astra satellite (19.2 SE)
<P>Frequency: 12640 MHz
<P>Polarization: V (Vertical)
<P>Symbol Rate: 22000 KS/s
<P>PIDs:
<P>
<UL>
<LI>Unicast: 512 (decimal), 0x200 (hexadecimal)</LI>
<LI>Multicast: 785, 786, 1041 (decimal), 0x311, 0x312, 0x411 (hexadecimal),
but you should notice that, in many cases, Multicast PIDs are taken in automatic.</LI>
</UL>
<P>We also need another info: what MAC address to assign to our DVB card.
<P>
<P>Again, for EON you can see Appendix A to calculate MAC address from dynamic
IP address.
<P>Obviously you need login and password to use ISP service.
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