Hello,
Here is the flowgraph. I see the spurs on an HP8563E with RBW at 30Hz
and span at 200Khz. I remember that it could be related to my spectrum
analyser : I will investigate in that direction before. But if someone
could make the test, it could be interesting. I use a N210 with LFTX and
LFRX.
-70dBc could be nothing for digital transmission but in analog use case,
as near as it is from the signal, -70dBc is not so good. For station
closed to that TX, it will be heard especially in HF usage.
Best regards,
Fabien, F4CTZ.
Le 01/02/2022 à 17:01, Marcus D. Leech a écrit :
On 2022-02-01 06:35, Fabien PELLET wrote:
Hello,
Thanks for the reply. As I wrote, I try several sampling rate on the
baseband I provide to the USRP without any effects on that spurs so
it is not related to the sampling rate. I just put a signal source
that feeds the USRP sink for that test.
It should be EMC related, as far as I understand reading all answer
on that mailing list.
Thanks,
Best regards,
Fabien, F4CTZ.
Could you share the exact flow-graph you're using?
Also, a spur at -70dBc can usually be ignored in any practical system
-- it's 10,000,000 times weaker than the carrier.
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