You're probably underflowing then (your CPU is not able to deliver
enough samples to the LimeSDR sink block). With the FM flow graph,
reduce the sweep time on your o-scope to see if you're actually
transmitting 100% of the time.
Ron
On 3/18/21 05:13, Anish Mangal wrote:
And, if I try the attach gnuradio file, which is just a constant
source of value '1' going to the limesdr sink block, I actually see a
sine-ish wave without the glitchy behavior.
On Thu, Mar 18, 2021 at 5:31 PM Anish Mangal <anis...@umich.edu
<mailto:anis...@umich.edu>> wrote:
I tried your grc and got the same result.
See the waveform's envelope in this oscilloscope capture. Note the
timebase.
https://drive.google.com/file/d/1b7PnpmvFfdQTDIwALuOzb22AzeffzR2w/view?usp=sharing
This isn't happening in SDRAngel.
On Thu, Mar 18, 2021 at 3:49 AM Cinaed Simson
<cinaed.sim...@gmail.com <mailto:cinaed.sim...@gmail.com>> wrote:
I moved the rational resampler block from the output side to
the input side of the WBFM.
The output of WBFM block needs to match the input of your
LimeSDR.
I don't have the LimeSDR software installed so I couldn't look
inside the sink block.
-- Cinaed
P.S - yes, you can post GRC's on the mailing list - they're
text based.
On 3/17/21 4:14 AM, Anish Mangal wrote:
I linked
<https://drive.google.com/file/d/1xQz1Kp_feAO1YrZRXXnMF25XEGgqVPSw/view?usp=sharing>
the grc file in the original email. Attaching it here as
well. (Don't know if the mailing list allows attachments)
On Wed, Mar 17, 2021 at 1:40 PM Cinaed Simson
<cinaed.sim...@gmail.com <mailto:cinaed.sim...@gmail.com>> wrote:
Hi Anish - since this is a gnuradio mailing list, the
starting point would be to post your GRC - which is an
yaml or text file.
-- Cinaed
On 3/16/21 11:19 PM, Anish Mangal wrote:
Hi! Any pointers to where I can start debugging this?
Maybe run gnuradio-companion in debug mode?
Do more simpler tests?
Any other suggestions?
I have a HackRF One and will try the exact same
comparison there too ... SDRAngel & grc
On Mon, Mar 15, 2021 at 7:32 PM Anish Mangal
<anis...@umich.edu <mailto:anis...@umich.edu>> wrote:
Hi,
To properly explain the issue I'm facing, I recorded
a video showing Oscilloscope waveforms.
https://drive.google.com/file/d/11anGShu-I3NhL9Jet6YAiyBprvwP4kDc/view?usp=sharing
The gnuradio flowgraph is here:
https://drive.google.com/file/d/1xQz1Kp_feAO1YrZRXXnMF25XEGgqVPSw/view?usp=sharing
The various versions of the software/hardware
involved are the following.
gnuradio-companion: 3.8.2.0 (Python 3.6.9)
gr-limesdr: branch gr-3.8 (last commit
47511dd58de1695b70e1028366411bada85eb60f)
sdrangel: 4.12.1
OS: Linux Mint 19.1
CPU: Intel© Core™ i7-4900MQ CPU @ 2.80GHz × 4
RAM: 16GB
H/w: Thinkpad T440p
tl;dr
I'm trying a simple test to create a sinewave output
from a WFM modulator block. If there is no audio
input, its WFM modulated signal should be a simple
sinewave. If I test this with SDRAngel, I see a
clean-ish actual sinewave in time domain on the
oscilloscope. But if I try to do the same with
gnuradio, it seems to produce a glitchy signal.
Could I have any advice on what I might be doing wrong?
Thanks,
Anish // VU2TVE
