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.
options:
parameters:
author: ''
catch_exceptions: 'True'
category: '[GRC Hier Blocks]'
cmake_opt: ''
comment: ''
copyright: ''
description: ''
gen_cmake: 'On'
gen_linking: dynamic
generate_options: qt_gui
hier_block_src_path: '.:'
id: defaultf
max_nouts: '0'
output_language: python
placement: (0,0)
qt_qss_theme: ''
realtime_scheduling: '1'
run: 'True'
run_command: '{python} -u {filename}'
run_options: prompt
sizing_mode: fixed
thread_safe_setters: ''
title: Not titled yet
window_size: (1000,1000)
states:
bus_sink: false
bus_source: false
bus_structure: null
coordinate: [8, 8]
rotation: 0
state: enabled
blocks:
- name: offset
id: variable_qtgui_range
parameters:
comment: ''
gui_hint: ''
label: ''
min_len: '200'
orient: QtCore.Qt.Horizontal
rangeType: float
start: '0'
step: 1e3
stop: 500e3
value: 26.5e3
widget: counter_slider
states:
bus_sink: false
bus_source: false
bus_structure: null
coordinate: [408, 20.0]
rotation: 0
state: true
- name: samp_rate_in
id: variable
parameters:
comment: ''
value: 200e3
states:
bus_sink: false
bus_source: false
bus_structure: null
coordinate: [176, 12.0]
rotation: 0
state: enabled
- name: samp_rate_out
id: variable
parameters:
comment: ''
value: 200e3
states:
bus_sink: false
bus_source: false
bus_structure: null
coordinate: [288, 12.0]
rotation: 0
state: enabled
- name: analog_sig_source_x_0
id: analog_sig_source_x
parameters:
affinity: ''
alias: ''
amp: '0.5'
comment: ''
freq: 1250+offset
maxoutbuf: '0'
minoutbuf: '0'
offset: '0'
phase: '0'
samp_rate: samp_rate_out
type: complex
waveform: analog.GR_COS_WAVE
states:
bus_sink: false
bus_source: false
bus_structure: null
coordinate: [408, 232.0]
rotation: 0
state: enabled
- name: uhd_usrp_sink_0
id: uhd_usrp_sink
parameters:
affinity: ''
alias: ''
ant0: '"TX/RX"'
ant1: '"TX/RX"'
ant10: '"TX/RX"'
ant11: '"TX/RX"'
ant12: '"TX/RX"'
ant13: '"TX/RX"'
ant14: '"TX/RX"'
ant15: '"TX/RX"'
ant16: '"TX/RX"'
ant17: '"TX/RX"'
ant18: '"TX/RX"'
ant19: '"TX/RX"'
ant2: '"TX/RX"'
ant20: '"TX/RX"'
ant21: '"TX/RX"'
ant22: '"TX/RX"'
ant23: '"TX/RX"'
ant24: '"TX/RX"'
ant25: '"TX/RX"'
ant26: '"TX/RX"'
ant27: '"TX/RX"'
ant28: '"TX/RX"'
ant29: '"TX/RX"'
ant3: '"TX/RX"'
ant30: '"TX/RX"'
ant31: '"TX/RX"'
ant4: '"TX/RX"'
ant5: '"TX/RX"'
ant6: '"TX/RX"'
ant7: '"TX/RX"'
ant8: '"TX/RX"'
ant9: '"TX/RX"'
bw0: '0'
bw1: '0'
bw10: '0'
bw11: '0'
bw12: '0'
bw13: '0'
bw14: '0'
bw15: '0'
bw16: '0'
bw17: '0'
bw18: '0'
bw19: '0'
bw2: '0'
bw20: '0'
bw21: '0'
bw22: '0'
bw23: '0'
bw24: '0'
bw25: '0'
bw26: '0'
bw27: '0'
bw28: '0'
bw29: '0'
bw3: '0'
bw30: '0'
bw31: '0'
bw4: '0'
bw5: '0'
bw6: '0'
bw7: '0'
bw8: '0'
bw9: '0'
center_freq0: 11e6-offset
center_freq1: '0'
center_freq10: '0'
center_freq11: '0'
center_freq12: '0'
center_freq13: '0'
center_freq14: '0'
center_freq15: '0'
center_freq16: '0'
center_freq17: '0'
center_freq18: '0'
center_freq19: '0'
center_freq2: '0'
center_freq20: '0'
center_freq21: '0'
center_freq22: '0'
center_freq23: '0'
center_freq24: '0'
center_freq25: '0'
center_freq26: '0'
center_freq27: '0'
center_freq28: '0'
center_freq29: '0'
center_freq3: '0'
center_freq30: '0'
center_freq31: '0'
center_freq4: '0'
center_freq5: '0'
center_freq6: '0'
center_freq7: '0'
center_freq8: '0'
center_freq9: '0'
clock_rate: 0e0
clock_source0: ''
clock_source1: ''
clock_source2: ''
clock_source3: ''
clock_source4: ''
clock_source5: ''
clock_source6: ''
clock_source7: ''
comment: ''
dev_addr: '"addr=192.168.10.2"'
dev_args: ''
gain0: '0'
gain1: '0'
gain10: '0'
gain11: '0'
gain12: '0'
gain13: '0'
gain14: '0'
gain15: '0'
gain16: '0'
gain17: '0'
gain18: '0'
gain19: '0'
gain2: '0'
gain20: '0'
gain21: '0'
gain22: '0'
gain23: '0'
gain24: '0'
gain25: '0'
gain26: '0'
gain27: '0'
gain28: '0'
gain29: '0'
gain3: '0'
gain30: '0'
gain31: '0'
gain4: '0'
gain5: '0'
gain6: '0'
gain7: '0'
gain8: '0'
gain9: '0'
gain_type0: default
gain_type1: default
gain_type10: default
gain_type11: default
gain_type12: default
gain_type13: default
gain_type14: default
gain_type15: default
gain_type16: default
gain_type17: default
gain_type18: default
gain_type19: default
gain_type2: default
gain_type20: default
gain_type21: default
gain_type22: default
gain_type23: default
gain_type24: default
gain_type25: default
gain_type26: default
gain_type27: default
gain_type28: default
gain_type29: default
gain_type3: default
gain_type30: default
gain_type31: default
gain_type4: default
gain_type5: default
gain_type6: default
gain_type7: default
gain_type8: default
gain_type9: default
len_tag_name: '""'
lo_export0: 'False'
lo_export1: 'False'
lo_export10: 'False'
lo_export11: 'False'
lo_export12: 'False'
lo_export13: 'False'
lo_export14: 'False'
lo_export15: 'False'
lo_export16: 'False'
lo_export17: 'False'
lo_export18: 'False'
lo_export19: 'False'
lo_export2: 'False'
lo_export20: 'False'
lo_export21: 'False'
lo_export22: 'False'
lo_export23: 'False'
lo_export24: 'False'
lo_export25: 'False'
lo_export26: 'False'
lo_export27: 'False'
lo_export28: 'False'
lo_export29: 'False'
lo_export3: 'False'
lo_export30: 'False'
lo_export31: 'False'
lo_export4: 'False'
lo_export5: 'False'
lo_export6: 'False'
lo_export7: 'False'
lo_export8: 'False'
lo_export9: 'False'
lo_source0: internal
lo_source1: internal
lo_source10: internal
lo_source11: internal
lo_source12: internal
lo_source13: internal
lo_source14: internal
lo_source15: internal
lo_source16: internal
lo_source17: internal
lo_source18: internal
lo_source19: internal
lo_source2: internal
lo_source20: internal
lo_source21: internal
lo_source22: internal
lo_source23: internal
lo_source24: internal
lo_source25: internal
lo_source26: internal
lo_source27: internal
lo_source28: internal
lo_source29: internal
lo_source3: internal
lo_source30: internal
lo_source31: internal
lo_source4: internal
lo_source5: internal
lo_source6: internal
lo_source7: internal
lo_source8: internal
lo_source9: internal
maxoutbuf: '0'
minoutbuf: '0'
nchan: '1'
num_mboards: '1'
otw: ''
samp_rate: samp_rate_out
sd_spec0: '"A:AB"'
sd_spec1: ''
sd_spec2: ''
sd_spec3: ''
sd_spec4: ''
sd_spec5: ''
sd_spec6: ''
sd_spec7: ''
show_lo_controls: 'False'
start_time: '-1.0'
stream_args: ''
stream_chans: '[]'
sync: none
time_source0: ''
time_source1: ''
time_source2: ''
time_source3: ''
time_source4: ''
time_source5: ''
time_source6: ''
time_source7: ''
type: fc32
states:
bus_sink: false
bus_source: false
bus_structure: null
coordinate: [856, 208.0]
rotation: 0
state: enabled
connections:
- [analog_sig_source_x_0, '0', uhd_usrp_sink_0, '0']
metadata:
file_format: 1
