# A small error in benchmark\_tx file

**URL:** <https://www.ruby-forum.com/t/a-small-error-in-benchmark-tx-file/243279>\
**Category:** GNU Radio\
**Created:** [September 8, 2015, 12:01am UTC](https://www.ruby-forum.com/t/a-small-error-in-benchmark-tx-file/243279 "2015-09-08T00:01:14Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Sadaf\_N](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/858c86/32.png) [@Sadaf\_N](https://www.ruby-forum.com/u/Sadaf_N)\
**Post date:** [September 8, 2015, 12:01am UTC](https://www.ruby-forum.com/t/a-small-error-in-benchmark-tx-file/243279/1 "2015-09-08T00:01:14Z")

</div>

Hi all,  
I have been trying to send data between 2 USRP’s from the benchmark\_tx  
file only to observe that I have been receiving this error.

Traceback (most recent call last):  
File “./benchmark\_tx.py”, line 147, in   
main()  
File “./benchmark\_tx.py”, line 111, in main  
tb = my\_top\_block(mods[options.modulation], options)  
File “./benchmark\_tx.py”, line 49, in **init**  
options.antenna, options.verbose)  
File  
“/usr/local/share/gnuradio/examples/digital/narrowband/uhd\_interface.py”,  
line 135, in **init**  
freq, gain, antenna)Hi all,  
I have been trying to send data between 2 USRP’s from the benchmark\_tx  
file only to observe that I have been receiving this error.

Traceback (most recent call last):  
File “./benchmark\_tx.py”, line 147, in   
main()  
File “./benchmark\_tx.py”, line 111, in main  
tb = my\_top\_block(mods[options.modulation], options)  
File “./benchmark\_tx.py”, line 49, in **init**  
options.antenna, options.verbose)  
File  
“/usr/local/share/gnuradio/examples/digital/narrowband/uhd\_interface.py”,  
line 135, in **init**  
freq, gain, antenna)  
File  
“/usr/local/share/gnuradio/examples/digital/narrowband/uhd\_interface.py”,  
line 62, in **init**  
self.\_rate, self.\_sps = self.set\_sample\_rate(bitrate, sps)  
File  
“/usr/local/share/gnuradio/examples/digital/narrowband/uhd\_interface.py”,  
line 70, in set\_sample\_rate  
asked\_samp\_rate = bitrate \* req\_sps  
TypeError: unsupported operand type(s) for \*: ‘float’ and ‘NoneType’

I am unable to understand what this error means? I have tried to search  
in the Internet about this but found nothing relevant. Please advice as  
to what I can do?

Thanks,  
Dave  
File  
“/usr/local/share/gnuradio/examples/digital/narrowband/uhd\_interface.py”,  
line 62, in **init**  
self.\_rate, self.\_sps = self.set\_sample\_rate(bitrate, sps)  
File  
“/usr/local/share/gnuradio/examples/digital/narrowband/uhd\_interface.py”,  
line 70, in set\_sample\_rate  
asked\_samp\_rate = bitrate \* req\_sps  
TypeError: unsupported operand type(s) for \*: ‘float’ and ‘NoneType’

I am unable to understand what this error means? I have tried to search  
in the Internet about this but found nothing relevant. Please advice as  
to what I can do?

Thanks,  
Dave

---

<div class="post-metadata">

**Author:** ![daveamos](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/a698b9/32.png) [@daveamos](https://www.ruby-forum.com/u/daveamos)\
**Post date:** [September 8, 2015, 12:05am UTC](https://www.ruby-forum.com/t/a-small-error-in-benchmark-tx-file/243279/2 "2015-09-08T00:05:54Z")

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Ravi,

I don’t understand – are you Dave Allen?

Best regards,  
Marcus