LNB Advice

[bigjohnuk]

Hi Guys,

Can some help me with what type of LNB works the best with the Dreambox

07dB ? or 0.3dB ?

Make and model ?

Kind regards

[wortmash]

using an Invacom 0.3 myself, no problems. Get the best spec you can, the DB is a bit insensitive.

[bigjohnuk]

So the smaller the number the better then

[jenkki700]

" DB is a bit insensitive."

So what does that mean? Is it enough just to have a LNB with a low noise level, or
do you need strong amplification/ output level as well?

I'm asking because I have problems with a maximum/digiality LNB. The db could not get a lock, so I had to disconnect the disecq-switch to make the transponder scan work. And I can still not get a
couple of channels with high symbolrates. The db reports SNR 85 AGC 82 and BER 10k-20k.

[gb2]

I have an old LNB wich has 0.9dB-noise, and a fixed osc. rate of 10000. (which means it can only go up to 11.9Ghz..)(can't remember the brand..)
and this LNB is much better than a brand new 0.3dB Universal LNB from humax.
With the old one I catch very weak signals without any glitches... and with the new one I don't even get a lock...

[Alias1]

Originally Posted by bigjohnuk

So the smaller the number the better then

From a technical point of view yes.
From a commercial point of view not necessarily. By that a lot of manufactures will put any thing on their LNB just to sell it.

[kaskas]

Try titanium lnb at 0.2db

[eriksla]

Originally Posted by bigjohnuk

Can some help me with what type of LNB works the best with the Dreambox
07dB ? or 0.3dB ?
Make and model ?

3x "plain" ALPS dual outputs in combination with visiosat "bisat" dish in NL, all sats' (astra 19.2, astra 26 and hotbird) reception perfect (SNR > 80).

Also the ALPS are very robust (contrary to the invacoms that break easily).

[eriksla]

Originally Posted by jenkki700

" DB is a bit insensitive."

So what does that mean? Is it enough just to have a LNB with a low noise level, or
do you need strong amplification/ output level as well?

I'm asking because I have problems with a maximum/digiality LNB. The db could not get a lock, so I had to disconnect the disecq-switch to make the transponder scan work. And I can still not get a
couple of channels with high symbolrates. The db reports SNR 85 AGC 82 and BER 10k-20k.

The word "insensitive" is a misnomer. What they actually mean is that the dm7000 and dm5600's are fitted with a tuner that gives up on a low-quality (low SNR) signal sooner than other sat receivers. It has _nothing_ to do with signal strength, so some sort of amplifier wouldn't help.

The problem only shows with certain sats at certain locations, I even suspect they're talking about reception of sats out of their official footprint.

Check the next things if you're experiencing low SNR and/or high BER:
- cables (high quality, all from 1 length, no water, no oxidation)
- dish alignment (two directions)
- lnb alignment (four directions!)

If you still have low SNR (< 60) or high BER (> 0) you might try a LNB with a lower noise figure, but I suspect a larger dish will help more.

Also check if there are any high-frequency sources in de neighbourhood of the dish, switches and the dreambox. If you have a dect telephone, move it somewhere else. BTW this is the only I can explain the combination of high SNR and high BER.

[Tom0000]

Each wire break (like switch) kills part of signal from dish.
If you have 2 breaks on line, you can use one pice of cable for test. This way you can simulate better LNB