Thanks for the reply.
I mentioned in my response to David's message that I'm purposefully setting the
duc frequency to 0 to transmit at baseband. Is using .tune to do this better
than the set_freq method even if I don't want duc to do anything to the signal?
Regards
Lance
----- Original Message ----
From: Eric Blossom <[EMAIL PROTECTED]>
To: David Scaperoth <[EMAIL PROTECTED]>
Cc: seph 004 <[EMAIL PROTECTED]>; discuss-gnuradio@gnu.org
Sent: Thursday, March 1, 2007 11:32:45 PM
Subject: Re: [Discuss-gnuradio] The shortest pulse length
On Thu, Mar 01, 2007 at 12:15:36PM -0500, David Scaperoth wrote:
> On 3/1/07, seph 004 <[EMAIL PROTECTED]> wrote:
> >
> > This is what I did:
> >
> >def build_graph ():
> > nchan = 1
> > interp = 512
> > duc0 = 0
> > duc1 = 0
> > fs = 250e3 #2nd sample rate
> >between usb and dac
> > max_dev = 32e3 #1st sample rate divided
> >by 4 (1st = 2nd sample rate)
> > gain = 16e3
> > k = 2 * math.pi * max_dev / fs
> > vec1 = Numeric.arange (0.624, 0.656, 0.0000128)
> > vsource = gr.vector_source_f(vec1, False)
> > fmmod = gr.frequency_modulator_fc (k)
> > amp = gr.multiply_const_cc(gain)
> >
> > fg = gr.flow_graph ()
> >
> > u = usrp.sink_c (0, interp, nchan)
> > tx_subdev_spec = (1, 0) #usrp.pick_tx_subdevice(u)
> > m = usrp.determine_tx_mux_value(u, tx_subdev_spec)
> > u.set_mux(m)
> > subdev = usrp.selected_subdev(u, tx_subdev_spec)
> > subdev.set_enable(True)
> >
> > sample_rate = u.dac_freq () / interp
> > u.set_tx_freq (0, duc0)
> > u.set_tx_freq (1, duc1)
> >
>
> Are you trying to use one daughter boards(nchen=1)? Why did you set duc0 =
> 0? that means your frequency will not be set at all. You do not need to
> do set_tx_freq() twice if you are using one daughter board. you only need :
> u.set_tx_freq (0, duc0) where duc0 is some frequency. Also, if you are
> using the basic daughterboards, you need to make sure that you have the
> output connector connect to TXA not TXB (according to your tx_subdev_spec)
>
>
> Hope this helped.
> David
Lance, you really want to be using tune, not set_tx_freq.
tune knows about all the daughterboards and does the right thing to
split the work between the digital upconverter and the RF front end (if any).
Take a look at fm_tx4.py or fm_tx_2_daughterboards.py
Eric
____________________________________________________________________________________
TV dinner still cooling?
Check out "Tonight's Picks" on Yahoo! TV.
http://tv.yahoo.com/
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
