You *really* are much better waiting for a true blind scanning DVB-S2 receiver to become available.
You will need the following equipment:
- Spectrum Analyzer
DVB-S Blind Scanner
PC DVB-S2 compatible card with DVBViewer software
TransEdit tool available from members section of DVBViewer website
Calculator
Pen and Paper
Lots of Patience
You can do the first two steps whichever way round you like, you just need to compare the results as in Step Three.
Step One
Blind scan the desired satellite between the range normally used for feeds using the DVB-S blind scanning receiver.
In this this case our satellite is Eurobird 4 which sits at 4 degrees east, and the feed range between 10950 to 11200 horizontal band only.
Note down all the results.
So for my example, the receiver found no signals.
Not the best for an example, in most cases you would pick up a few signals.
If the blind scan range is increased to 11300 then found one signal at 11229 h 23148 3/4
Step Two
Look at the satellite through the Spectrum Anazlyer and note down the signal peaks for the feed range.
See the image below for an example.
The higher the peak the stronger the signal.
Before someone moans the actual colour scheme is different on the television image, the method I use for capturing the image messes it up.
Very quick guide to the controls.
Use the Outdoor unit button to change everything to the desired settings.
PWR: 13V for vertical polarization, 17V for horizontal polarization.
22kHZ: off is low band, 10700 to 11900 and on is high band, 11550 to 12750.
These are true for your bog standard Ku Band Universal LNB.
IF: this is the frequency from the LNB, you need to add a value to this for the end frequency to tune the receiver with.
Low band (22kHZ off) then add 9750 to the IF value.
High band (22kHZ on) then add 10600 to the IF value.
So for the image, call it IF 1305 plus 9750 gives us a frequency to tune of 11055
According to our spectrum analyzer plot, there are the following peaks.
10960
11056
11137
11183
11229
11422
11766 then a few smaller peaks in a row
We only need worry about the range from 10950 to 11200, so that cuts it down a bit.
Now cross reference the DVB-S blind scan results against the peaks.
In this case no results were found so we have some unidentified signals
Namely, 10960, 11056, 11137 and 11183
From past experience I know that the peaks at 10960,11137 and 11183 are nothing.
So that leaves us with a large unidentified signal at 11055
Step Three
We have a possible signal so we will scan this in DVB-S2 using some common symbol rates to see if we get lucky.
For this I use the TransEdit tool, you could maybe use other DVB Software but this is my preferred method.
Start TransEdit, pick the desired satellite from the Transponder List File window on the left, in this case 4e.
Now on the right hand window near the bottom press Blind Scan button.
Fill out the Parameter Ranges on the Blind Scan dialog as follows.
Frequencies: 11055
Symbolrates: 7200,14400,20000,20926,26666,27745,27500,28800
Polarisations: 0
Modulations: 0
Pilot Symbols: 0
FEC Values: 0
DVB-S/DVB-S2: 1
Roll-Off Values: 0
Press Apply then Scan and the Scanner window should open.
It will now scan our target signal going through the symbol rates listed and hopefully find something.
Bingo
Notes
The method described here relies on a couple of things.
Firstly, that you can identify the signal peaks from the spectrum, when multiple feeds are in close proximity then it is not so easy.
Secondly, the feed is using a common symbol rate.
If the above steps did not find any results then you can either give the signal up as background noise, or go back to the Blind Scan dialog and try different symbol rates.
Tip, if you enter 10000-20000:40 then it will scan 10000 to 20000 in steps of 40
Be warned though this can be very time consuming and often give no results.
Also check that the signal is still there from time to time otherwise you will be scanning for nothing.
Good luck and Happy Hunting.
womble
This guide was written for the following sites.
http://groups.google.com/group/feedhunter
http://www.sat-benelux.nl/
2008-09-09 @ 23:34