quality vs signal

[ding]

Hi,what could cause the quality bar on the receiver to show 90%,
and the signal strength 50/60% and still doesn't show a weak signal.
the pictures they still show ok. thanks for any input guys.

[Terryl]

Quality (Q) is the indication on how good the software is decoding the digital information from the satellite.

Signal (S) is the amount of signal from the LNB to the reciver, it can be quite low (30 to 40%) and you can still have a great picture.

This is a digital signal, not like the old analog signal where you needed every micro volt of signal to get a good picture.


The "Q" signal is dervived from a calculated bit error rate, or how hard the forward error correction (FEC) has to work to correct any missing data bits.

The "S" indication is the level of the signal after it's down converted inside the LNB to something that will go down a standard coax, most satellite signal are in the 11 to 12 GHz band, this is too high in frequecy to send down standard coax, so it is down converted to a 900 to 1400 MHz signal, it is this signal that the "S" measurment is derived from.

[stman]

What type lnb switch do you have and what grade of coax? Length of cable run?

[Terryl]

A low "S" indication could be related to, too long a run of cheap or wrong type of coax, coax for CATV will not work too good on satellite systems, it has to be swept or rated to 2.5 to 3 GHz.

If you use cheap coax and it is too long a run say over 100 feet, your "S" reading will be low.

If this is the case the using good RG-6 quad shielded coax will help, some coax has a copper plated steel center conductor (cheap stuff) using good coax with a pure copper center conductor will also help.

And it all should be rated to 2.5 to 3 GHz, some CATV coax only goes to 950 MHZ, this wont work too good, as the system loss would be too high.


Also a bad switch or corroded connectors will/could cause a low "S" reading.

[ding]

Hi,
i am using a emp-centauri switch,coaxial cable RG6 running 160 ft.