Satellite Connection Question

DANO · 03-03-2008

If cable connections are extended in the house by barrel type connectors will this degrade the Hi Def signal and video ?

**rolfw** · 03-03-2008

It will attenuate the signal slightly (depend how long you are extending by and the initial signal strength), but shouldn't affect the signal quality to any significant degree.

**4dbennett** · 03-03-2008

Barrel connectors deplete the signal strength by 10%, i have two feeds off a four feed lnb and they are of the same length cable except one has a join with a barrel connector and the signal strength is exactly 10% lower, the signal quality is unaffected.

regards dave

**rolfw** · 03-03-2008

It won't be by a percentage Dave, it will be a fixed db loss, haven't measured, but I would guess one db at low IF and 2 at high IF. The percentage will vary depending on your original signal strength.

Just taken a couple of measurements and these are without barrel and with barrel connected to a 3m patch cable.

10719 mhz (IF 9750mhz) - 72.1db/microvolt without, 70.2db with cable and barrel connector, no difference in noise margin or BER.

12600 mhz (IF 2000mhz) - 63.2db/microvolt without, 60.1db with cable and barrel connector, no difference in noise margin or BER.

**Robbo** · 03-03-2008

So that's worse case about 3dBs loss then, which means you lose approx 30% of the signal voltage you had on the input to the barrel.

Equal to about 10m of satellite cable.

**tesla** · 05-03-2008

Originally Posted by 4dbennett

Barrel connectors deplete the signal strength by 10%, i have two feeds off a four feed lnb and they are of the same length cable except one has a join with a barrel connector and the signal strength is exactly 10% lower, the signal quality is unaffected.

regards dave

I haven't tested a signal before and after the connection. However, there are some other parameters. If the connectors are not fitted to the cable properly then the signal loses its strength because of bad work.

If the connection is outdoors then it should be protected from rain.

**4dbennett** · 05-03-2008

Originally Posted by Robbo71

So that's worse case about 3dBs loss then, which means you lose approx 30% of the signal voltage you had on the input to the barrel.

Equal to about 10m of satellite cable.

NICE %,s Robbo

dave

**Robbo** · 05-03-2008

Originally Posted by 4dbennett

NICE %,s Robbo

dave

Not nice no, but true.

20*log(0.7)=-3.

thus -3dB means you have 0.7 of what you had before, so you've lost 30% of the signal voltage.

or 3dB represents a signal power loss of 50%.
(10*log(0.5)=-3)

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Satellite Connection Question Information exchange on digital satellite systems other than Sky

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