# Writing a simple Tx Program in GRC that transmits a cosine signal

**URL:** <https://www.ruby-forum.com/t/writing-a-simple-tx-program-in-grc-that-transmits-a-cosine-signal/179277>\
**Category:** GNU Radio\
**Created:** [November 20, 2009, 11:04pm UTC](https://www.ruby-forum.com/t/writing-a-simple-tx-program-in-grc-that-transmits-a-cosine-signal/179277 "2009-11-20T23:04:51Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Adam\_Lee](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7bcc69/32.png) [@Adam\_Lee](https://www.ruby-forum.com/u/Adam_Lee)\
**Post date:** [November 20, 2009, 11:04pm UTC](https://www.ruby-forum.com/t/writing-a-simple-tx-program-in-grc-that-transmits-a-cosine-signal/179277/1 "2009-11-20T23:04:51Z")

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Hello all, I have been able to write a fm receiver in GRC using the 2.4g  
daughterboard but as of now i can only test getting noise using the fft  
graphical sink. Does anyone know how to make a simple Tx in GRC and the  
corresponding blocks that go with it?

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**Author:** ![Adam\_Lee](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7bcc69/32.png) [@Adam\_Lee](https://www.ruby-forum.com/u/Adam_Lee)\
**Post date:** [November 21, 2009, 7:09am UTC](https://www.ruby-forum.com/t/writing-a-simple-tx-program-in-grc-that-transmits-a-cosine-signal/179277/2 "2009-11-21T07:09:22Z")

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Adam Lee wrote:

> Hello all, I have been able to write a fm receiver in GRC using the 2.4g  
> daughterboard but as of now i can only test getting noise using the fft

Theres not a lot of fm being transmitted in the 2.4ghz range…

> graphical sink. Does anyone know how to make a simple Tx in GRC and the  
> corresponding blocks that go with it?

For a cosine signal, connect a signal source to a usrp sink. The  
amplitude should be around 10k.

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<div class="post-metadata">

**Author:** ![Adam\_Lee](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7bcc69/32.png) [@Adam\_Lee](https://www.ruby-forum.com/u/Adam_Lee)\
**Post date:** [February 3, 2010, 3:52am UTC](https://www.ruby-forum.com/t/writing-a-simple-tx-program-in-grc-that-transmits-a-cosine-signal/179277/3 "2010-02-03T03:52:23Z")

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Josh B. wrote:

> Adam Lee wrote:
> 
> > Hello all, I have been able to write a fm receiver in GRC using the 2.4g  
> > daughterboard but as of now i can only test getting noise using the fft
> 
> Theres not a lot of fm being transmitted in the 2.4ghz range…
> 
> > graphical sink. Does anyone know how to make a simple Tx in GRC and the  
> > corresponding blocks that go with it?
> 
> For a cosine signal, connect a signal source to a usrp sink. The  
> amplitude should be around 10k.

I’m new to Gnuradio prorgramming and im exploring the various options  
that v have out here..

I tried connecting a sine source to a scope sink ..I get the gui however  
it is not plotting the waveform .. and it gets hung after few seconds.  
Can sum1 throw light on this.. Also can some1 explain why is sampling  
rate specified for the blocks here.. coz we will not need sampling to  
simply display an analog signal on the scope…

Thanks & Regards,  
Poornashree

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**Author:** ![Adam\_Lee](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7bcc69/32.png) [@Adam\_Lee](https://www.ruby-forum.com/u/Adam_Lee)\
**Post date:** [February 5, 2010, 9:21am UTC](https://www.ruby-forum.com/t/writing-a-simple-tx-program-in-grc-that-transmits-a-cosine-signal/179277/4 "2010-02-05T09:21:16Z")

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Hello people …

The problem of the system getting hung is resolved…  
However is there anybody who can explain the logic of sampling rate  
mentioned in those blocks in grc?

Thanks & Regards,  
Poornashree