Re: [Discuss-gnuradio] help -- how to implement transmitting periodic on/off tones

2010-11-29 Thread madengr
Yes, LO leakage, more specifically DC imbalance in the I and Q channels; I assume you are using a daughter board with an IQ modulator? This is supposedly corrected for in the firmware, however, probably not done over temperature. You can probably tweak it by adding/subtracting a few LSB of DC of

Re: [Discuss-gnuradio] help -- how to implement transmitting periodic on/off tones

2010-11-29 Thread Marcus D. Leech
On 11/29/2010 01:35 PM, Steven Clark wrote: One would think something like this would work, but I've noticed that even if you're sending 0's to your usrp sink, the transmitter still puts out some amount of power (plenty strong enough to be detectable via a spec-an). This power goes away if y

Re: [Discuss-gnuradio] help -- how to implement transmitting periodic on/off tones

2010-11-29 Thread Steven Clark
> Think of the on/off part as a control stream consisting of 1's and > 0's. Generate the control stream, and multiple the control stream by > the carrier stream. > > Don't try to start and stop the graph or anything like that from > python. > > You can probably generate the control stream with a >

Re: [Discuss-gnuradio] help -- how to implement transmitting periodic on/off tones

2010-11-29 Thread Eric Blossom
On Mon, Nov 29, 2010 at 12:42:38AM -0800, Steve Mcmahon wrote: > Hello: > I have a USRP2 board and a WBX daughterboard. I am trying to > implement a scheme where a single-tone sine wave (at frequencies > between 1 kHz and 10 kHz) is transmitted > intermittently. Specifically, time is divided into

[Discuss-gnuradio] help -- how to implement transmitting periodic on/off tones

2010-11-29 Thread Steve Mcmahon
Hello: I have a USRP2 board and a WBX daughterboard. I am trying to implement a scheme where a single-tone sine wave (at frequencies between 1 kHz and 10 kHz) is transmitted intermittently. Specifically, time is divided into intervals, defined by the user on the command line, typically of value