Promax prolink 4 Help!

[landcruiser]

I was wondering if someone could point me in the right direction as were im going wrong?

I use the spectrum and chose the higest marker on the spectrum and tune, then when tunning lnb i tune the lowest signal.... After tunning hotbird and spectrum showed me the db going up , i found more channels but most of the have ber?

Also astra 28.2 fine tune today lost me a couple of channels ? even though on the higest and lowest i have seen an improved db......

Could the promax need recalbriation or im i using it somehow wrong?

James

 

[vma]

Hi,

There is more to aligning a dish than just looking at the spectrum.

With the spectrum you will see that there is a satellite, you will see its transponders and you will be able to maximise the SIGNAL LEVEL.

For analog broadcasts that was enough. You may want to look at C/N, which is the ration between the signal and the background noise: the signal needs to be clearly above the noise, so that the receiver can distinguish between noise and signal.

With digital transmissions, however, you have to look at further parameters: BER and MER.

BER = Bit Error Rate
MER = Modulation Error Ratio

The first counts the erroneous bits received over a period of time. Some meters distinguish between b-BER (Before or Pre) and a-BER (after), indicating if the error rate is taking the correction algorithm into account.

MER will give you an idea on how good the signal fits in its quadrant. You should first get a good MER then optimize BER. BER is more of an indication of intermittent and/or quickly changing issues of the reception, while MER will give an overall indication of the quality of the communication.

You can read more of this here: _http://www.scte-chesapeakechapter.org/presentations/BER%20and%20MER%20Fundamentals.pdf

The constellation diagram will show you the consequences of MER and BER graphically.

After rotating the dish to a maximum peak on the spectrum, you MUST consider MER, BER and the constellation and further optimize the alignment until you get the lowest possible MER and BER.

Finally, the tilting of the LNB is very important, as it needs to match the orientation of the V and H planes transmitted by the satellite. If your LNB is not correctly aligned, the transponders of the V band will interfere on the H band and vice versa, thus decreasing the C/N I mentioned earlier.

Hope this helps.

Cheers,
vma