DBS-RX satellite connection

GNU Radio
1

I would like to get my usrp conneced to my TVRO satellite dish. I am
wondering…
Is the DBSRX daughter card suitable for direct connection to a satellite
LNB?
I am thinking it will be easier to let the sat receiver do the lnb
power and polarization control
Is it be safe to connect to the lnb loop-through connection on
standard satellite receivers?

dave

2

On Sat, Jun 06, 2009 at 02:30:05AM -0400, davek wrote:

I would like to get my usrp conneced to my TVRO satellite dish. I am
wondering…
Is the DBSRX daughter card suitable for direct connection to a satellite LNB?

Yes.

I am thinking it will be easier to let the sat receiver do the lnb
power and polarization control
Is it be safe to connect to the lnb loop-through connection on
standard satellite receivers?

I don’t know.

Eric

3

davek wrote:

I would like to get my usrp conneced to my TVRO satellite dish. I am
wondering…
Is the DBSRX daughter card suitable for direct connection to a satellite LNB?
I am thinking it will be easier to let the sat receiver do the lnb
power and polarization control
Is it be safe to connect to the lnb loop-through connection on
standard satellite receivers?

I am not sure exactly what you are asking. The DBSRX RF path is DC
blocked, so you can put DC bias on the line externally without problem.
You could also use the DBSRX’s built-in bias tee to do this if you
like, as long as you keep the current below 500mA.

Matt

4

most sat boxes have a IF output for secondary receiver, i will use the
reciever to power the motor / lnb / polariztion control. just wanted
to make sure any crap coming down the line wont blow up the dbsrx but
it sounds safe
thanks

5

On Sat, 2009-06-06 at 21:57 -0700, Eric B. wrote:

standard satellite receivers?

I don’t know.

I have done that in the past and it worked fine.
(I did analog satelite TV reception which is FM modulated.
I just switched the AM-demod block in usrp_tv_receive.py for a
quadrature-demod block (=FM demodulator) and reduced decimation and got
an image. You get some distortion because you can’t get the complete
bandwidth of a sattelite channel usring a USRP-1. (Best I got was 16 MHz
using 8 bits/sample and decimation 4 )

Using the sat-receiver for power and polarisation is very conveniant.
You can use the remote to switch polarisation.

Greetings,
Martin