N200 strong spikes

GNU Radio
1

Hi all,

I am using a N200+WBX with samplerate = 5e6, no input signal.

Independently on the tuning frequency I have two strong spikes about 1
MHz far (see attached picture on 500 MHz tuning frequency).

http://img189.imageshack.us/img189/7707/spikesf.jpg

I have a similar situation on 434 MHz band and also changing sample
rate to 10e6;

Is it a known problem or something is wrong in my setup ?

Luca

2

Hi Luca,

I’ve been running into a similar problem with random spikes. Are you
just running uhd_fft.py? Have you tried using
benchmark_rx.py/benchmark_tx.py?

-Jason

From: Luca P. [email protected]
To: [email protected]
Sent: Thursday, May 3, 2012 8:18 AM
Subject: [Discuss-gnuradio] N200 strong spikes

Hi all,

I am using a N200+WBX with samplerate = 5e6, no input signal.

Independently on the tuning frequency I have two strong spikes about 1
MHz far (see attached picture on 500 MHz tuning frequency).

http://img189.imageshack.us/img189/7707/spikesf.jpg

I have a similar situation on 434 MHz band and also changing sample
rate to 10e6;

Is it a known problem or something is wrong in my setup ?

Luca

3

Hi Jason,

No, I am just using UHD driver.
The processing to perform FFT and so on has been developed by myself.
But I am quite sure that the processing is ok because with other
receivers works fine and
it provides correct results according to the test signals.

Moreover now seams that the span between the 2 spikes it’s not
constant (I made some test with 2 MHz span instead of 1 MHz).
I suspect that should be some spurious due to the local oscillator
onboard WBX ??

Luca

2012/5/3 Jason T. [email protected]:

Sent: Thursday, May 3, 2012 8:18 AM
http://img189.imageshack.us/img189/7707/spikesf.jpg
[email protected]
Discuss-gnuradio Info Page

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Ing. Luca P.
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