Problem with arguments in benchmark_tx and rx

GNU Radio
1

I am using USRP with RFX2400.
Was trying with benchmark_tx and benchmark_rx
I connected RFX board to the B side of transmiter USRP and connected RFX
board to the A side of receiver USRP.
For connection I used SMA-SMA connector.
With the help file I understood almost everything but how to specify the
transmitter and receiver ports i.e.
I connected SMA to TX/RX of transmitter (side B in USRP ) then is the
following command correct …
./benchmark_tx.py -f 2.45G --tx-amplitude=0.5 -v --show-tx-gain-range -T
B
And for receiver part I connected SMA to RX2 (side A of USRP) then is
the
following command correct…
./benchmark_rx.py -f 2.45G -v --show-rx-gain-range -R A

With these commands nothing happens at the receiver end…I would like
to
know what things I missed/misunderstood :slight_smile:

I was playing well with the basix TX and Rx daughter boards but getting
problems with RFX.

Sumit Kr.
Research Assistant
Communication Research center
IIIT Hyderabad
India

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2

I got a reply for this post by Nick F. but its not showing
here.Anyways I
am posting It here

Nick answered — “So, first of all, you’re using an attenuator, right?
You
can’t transmit directly from one RFX2400 into another without the
possibility of damaging the receiving RFX2400.”

–n

Nick … I connected them using SMA-SMA cables.Does this mean that I
have
damaged them already ?
I thought these cables will provide the required attenuation.

Anyways I have a general question…
I have two basic Tx and Rx daughter boards.
say I put the Transmitter daughter board on side A of USRP.Now the
Transmitter daughter board has two ports TX-A and TX-B. What should I
write
for the arguments while running benchmark_tx.py
Iis the following correct …

Side A and TX-A ----> -T A:0
Side A and TX-B ----> -T A:1
Side B and TX-A ----> -T B:0
Side B and TX-B ----> -T B:1

sumitstop wrote:

./benchmark_tx.py -f 2.45G --tx-amplitude=0.5 -v --show-tx-gain-range -T B

Sumit Kr.
Research Assistant
Communication Research center
IIIT Hyderabad
India

View this message in context:
http://old.nabble.com/Problem-with-arguments-in-benchmark_tx-and-rx-tp32381731p32382516.html
Sent from the GnuRadio mailing list archive at Nabble.com.

3

On Thu, Sep 1, 2011 at 4:39 PM, sumitstop
[email protected] wrote:

Nick … I connected them using SMA-SMA cables.Does this mean that I have
Side A and TX-A ----> -T A:0
Side A and TX-B ----> -T A:1
Side B and TX-A ----> -T B:0
Side B and TX-B ----> -T B:1

SMA cables have very little attenuation. Look at the table of cables
at Coaxial cable - Wikipedia. You can see that cables
are rated for a few dB of attenuation per 100 feet. You definitely
need real attenuators in line with your cables in your setup.

Tom