USRP1+external VUHF Tuner and C++ Interface

GNU Radio
1

Hi all,

I am trying to use USRP1 with an external Tuner using the C++ USRP
interface
example founded on the wiki.
The Tuner have a 16 MHz BW centered at 21.4MHz IF.
I have connected it (passing through a passband filter centered @21.4M
and
16M wide) to USRP using the BasicRX daughterboard. I have some doubt
about
this setup.

A) Do I need to control in someway (by a “driver”) the doughterboard?

B) How should I have to set the DDC freq ( set_rx_freq() ) to get
correctly
the signals around the 21.4M IF ?

Thanks in advance,

LUCA

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2

On Wed, Jul 29, 2009 at 02:31:12PM -0700, Luca P. wrote:

A) Do I need to control in someway (by a “driver”) the doughterboard?

B) How should I have to set the DDC freq ( set_rx_freq() ) to get correctly
the signals around the 21.4M IF ?

Thanks in advance,

usrp_tune_result r;
bool ok = u->tune(0, db, 21.4e6, r);

Eric

3

Hi Eric,
thanks for your reply.
Now seems work something more.
Next Two things I have to investigate are :

  1. I have a tone in the middle of the spectrum regardlss of the input
    signal. What should be ?
    2)db->is_quadrature() return true. What does it exactly means ? (i set
    urx->set_format(0x00000300)-default).

Thanks again,
Luca

Eric B. wrote:

and
Thanks in advance,
Discuss-gnuradio Info Page

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