Re: LINEARITY - MEASUREMENTS
I was and am using "Average".
Dave - W?LEV
Hi Dave,
What detection mode are you using in Radio-SkyPipe???
I was intrigued by the calibration of the standard RJ setup.? While I do not use that setup, I decided to measure what I use for other purposes, including RJ.? So, have a read of the attachment.? I'm using the AirSpy Discovery HF+ to test the linearity.? The system is diagrammed to start and then, I ran an HP generator up by 10 dB steps ultimately into Radio SkyPipe.? I was somewhat disappointed at the non-linear behavior of the system.? Please have a read of the attachment.
CONCLUSION:? Yes, calibration is needed if linear response to the input is required!!!
Dave - W?LEV
|
Re: Solar 05/24/2025 Easley, South Carolina
Salvador: ? ? ? Indeed you do. Thanks.
On Saturday, May 24, 2025, 8:43 PM, salvador aguirre via groups.io <drsaguirre@...> wrote: Hi John
?
I think I have your events but they are very weak.
?
Salvador
|
Re: LINEARITY - MEASUREMENTS
Hi Dave,
What detection mode are you using in Radio-SkyPipe???
I was intrigued by the calibration of the standard RJ setup.? While I do not use that setup, I decided to measure what I use for other purposes, including RJ.? So, have a read of the attachment.? I'm using the AirSpy Discovery HF+ to test the linearity.? The system is diagrammed to start and then, I ran an HP generator up by 10 dB steps ultimately into Radio SkyPipe.? I was somewhat disappointed at the non-linear behavior of the system.? Please have a read of the attachment.
CONCLUSION:? Yes, calibration is needed if linear response to the input is required!!!
Dave - W?LEV
|
Re: Solar 05/24/2025 Easley, South Carolina
Hi John
?
I think I have your events but they are very weak.
?
Salvador
|
Re: Solar Events, 24 May 2025, Prospect, ME
Bill
I'm getting the same signal out here on the west coast of Canada.
John? P
--
This email has been checked for viruses by AVG antivirus software.
www.avg.com
|
Solar Events, 24 May 2025, Prospect, ME
Good evening...
Just two events captured today.
The persistent, very strong signal at about 21 Mhz is odd/weird. There are no American (ARRL) amateur radio contests in May that might explain it.
...bill...
|
Re: The FFT and nuclear weapons
If possible please attach and send a pdf of these historical references on FFTs. Thanks!
Here are 2 papers about the history of FFT, the second by Heindeman, et al. has an extensive bibliography for those wishing to go deep into the historical "weeds":
?
PROIECEEEE.D INTGHSE OF VOL. 5 5 . N16O7.5 10 . O1C96T7O BER
Historical Notes on the Fast Fourier Transform
JAMES W. COOLEY, PETER A. W. LEWIS, AND PETER D. WELCH
?
Heideman, M.T., Johnson, D.H. & Burrus, C.S. Gauss and the history of the?
fast Fourier transform. Arch. Hist. Exact Sci. 34, 265¨C277 (1985).?
?
? seattle ? physics541 ? 2010-Fourier-transforms ? history-3.pdf
?
.....bill....
|
Solar 05/24/2025 Easley, South Carolina
Good evening: ? ? ?Finally, a bit of solar from today.
John
|
Re: The FFT and nuclear weapons
Here are 2 papers about the history of FFT, the second by Heindeman, et al. has an extensive bibliography for those wishing to go deep into the historical "weeds":
?
PROIECEEEE.D INTGHSE OF VOL. 5 5 . N16O7.5 10 . O1C96T7O BER
Historical Notes on the Fast Fourier Transform
JAMES W. COOLEY, PETER A. W. LEWIS, AND PETER D. WELCH
?
Heideman, M.T., Johnson, D.H. & Burrus, C.S. Gauss and the history of the?
fast Fourier transform. Arch. Hist. Exact Sci. 34, 265¨C277 (1985).?
https://doi.org/10.1007/BF00348431?
https://faculty.washington.edu ? seattle ? physics541 ? 2010-Fourier-transforms ? history-3.pdf
?
.....bill....
|
Re: Solar Activity reported by this group.
How bought a peer reviewed "real" science paper instead?
Chuck, Looks like that could be written up as a good Citizen Science project.?
Hi Chuck, I am sure that what your students did was more accurate.?As the number of observers has grown so would the total observation number for any given week, as I am just using the number of reported?observations.? It is very rough.?? Jim
On Fri, May 23, 2025 at 10:55?AM Chuck Higgins via <Chuck.Higgins= [email protected]> wrote:
Hey Jim and all,
?
? This is fantastic. AI and a good human brain -- to double-check the AI brain -- are going to
be game changers in research and data analysis. This is a great example. I¡¯m trying to get
my student to write some python code to help count solar bursts, and we¡¯ve had some success,
but not yet good enough.
??This is my old-fashioned method of using students (they were paid) to count solar bursts
on Radio-Skypipe records from 2005 to 2018. Again, trying to get a student to bring this
graph up to date but it¡¯s slow going.
?
Cheers,
?
Chuck
?
?
Below is a chart showing reported solar activity by this group since it started.? This was done with ChatGPT's help and only includes new posts with an image and using keywords. It is just an approximate value.? The idea was to see if our
activity on this group approximates the solar activity (using sunspot number because it was easy to get) and as an exercise for me to see if something might be done to facilitate archiving these curated reports.? ?All of the activity of this group was downloaded
as a single 12 GB mbox file which was then used to produce a single filtered CSV file.? GPT then analyzed the CSV file and produced a python program the does the histogram.??
Jim Sky?
radiosky at radiosky dot com
|
Re: Solar Activity reported by this group.
Chuck, Looks like that could be written up as a good Citizen Science project.?
Hi Chuck, I am sure that what your students did was more accurate.?As the number of observers has grown so would the total observation number for any given week, as I am just using the number of reported?observations.? It is very rough.?? Jim
On Fri, May 23, 2025 at 10:55?AM Chuck Higgins via <Chuck.Higgins= [email protected]> wrote:
Hey Jim and all,
?
? This is fantastic. AI and a good human brain -- to double-check the AI brain -- are going to
be game changers in research and data analysis. This is a great example. I¡¯m trying to get
my student to write some python code to help count solar bursts, and we¡¯ve had some success,
but not yet good enough.
??This is my old-fashioned method of using students (they were paid) to count solar bursts
on Radio-Skypipe records from 2005 to 2018. Again, trying to get a student to bring this
graph up to date but it¡¯s slow going.
?
Cheers,
?
Chuck
?
?
Below is a chart showing reported solar activity by this group since it started.? This was done with ChatGPT's help and only includes new posts with an image and using keywords. It is just an approximate value.? The idea was to see if our
activity on this group approximates the solar activity (using sunspot number because it was easy to get) and as an exercise for me to see if something might be done to facilitate archiving these curated reports.? ?All of the activity of this group was downloaded
as a single 12 GB mbox file which was then used to produce a single filtered CSV file.? GPT then analyzed the CSV file and produced a python program the does the histogram.??
Jim Sky?
radiosky at radiosky dot com
|
Re: Solar Activity reported by this group.
Hi Chuck, I am sure that what your students did was more accurate.?As the number of observers has grown so would the total observation number for any given week, as I am just using the number of reported?observations.? It is very rough.?? Jim
On Fri, May 23, 2025 at 10:55?AM Chuck Higgins via <Chuck.Higgins= [email protected]> wrote:
Hey Jim and all,
?
? This is fantastic. AI and a good human brain -- to double-check the AI brain -- are going to
be game changers in research and data analysis. This is a great example. I¡¯m trying to get
my student to write some python code to help count solar bursts, and we¡¯ve had some success,
but not yet good enough.
??This is my old-fashioned method of using students (they were paid) to count solar bursts
on Radio-Skypipe records from 2005 to 2018. Again, trying to get a student to bring this
graph up to date but it¡¯s slow going.
?
Cheers,
?
Chuck
?
?
Below is a chart showing reported solar activity by this group since it started.? This was done with ChatGPT's help and only includes new posts with an image and using keywords. It is just an approximate value.? The idea was to see if our
activity on this group approximates the solar activity (using sunspot number because it was easy to get) and as an exercise for me to see if something might be done to facilitate archiving these curated reports.? ?All of the activity of this group was downloaded
as a single 12 GB mbox file which was then used to produce a single filtered CSV file.? GPT then analyzed the CSV file and produced a python program the does the histogram.??
Jim Sky?
radiosky at radiosky dot com
|
Re: Solar Activity reported by this group.
I saw that too Bill.? Christmas shopping?? I think we may be the only game in town for HF solar bursts.? I think NOAA may have a 245 MHz radio dataset.?
Jim
Thanks...as someone who is new to this "game" some interesting gaps in reports during the Fall and Early winter of 2024-2025.
?
I wonder how the graph would look it events reports by the experts in Solar Events Reports were included? Beyond me to included them!
...bill....
|
Re: Solar Activity reported by this group.
Hey Jim and all,
?
? This is fantastic. AI and a good human brain -- to double-check the AI brain -- are going to
be game changers in research and data analysis. This is a great example. I¡¯m trying to get
my student to write some python code to help count solar bursts, and we¡¯ve had some success,
but not yet good enough.
??This is my old-fashioned method of using students (they were paid) to count solar bursts
on Radio-Skypipe records from 2005 to 2018. Again, trying to get a student to bring this
graph up to date but it¡¯s slow going.
?
Cheers,
?
Chuck
?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]>
On Behalf Of Jim Sky via groups.io
Sent: Thursday, May 22, 2025 12:20 AM
To: [email protected]
Subject: [EXTERNAL] [Radio JOVE] Solar Activity reported by this group.
?
Below is a chart showing reported solar activity by this group since it started.? This was done with ChatGPT's help and only includes new posts with an image and using keywords. It is just an approximate value.? The idea was to see if our
activity on this group approximates the solar activity (using sunspot number because it was easy to get) and as an exercise for me to see if something might be done to facilitate archiving these curated reports.? ?All of the activity of this group was downloaded
as a single 12 GB mbox file which was then used to produce a single filtered CSV file.? GPT then analyzed the CSV file and produced a python program the does the histogram.??
Jim Sky?
radiosky at radiosky dot com
|
Re: Solar Activity reported by this group.
Thanks...as someone who is new to this "game" some interesting gaps in reports during the Fall and Early winter of 2024-2025.
?
I wonder how the graph would look it events reports by the experts in Solar Events Reports were included? Beyond me to included them!
...bill....
|
Re: Views of the Solar "Storm" from the Dark Sky Observatory May 13, 2025
Hi Larry,
?
SDRc2RSS reports that the noise floor is at -143.6dBm.
?
Richard
|
Re: LINEARITY - MEASUREMENTS
Thanks, Jim, for once again making me read the description of Radio SkyPipe.? I've searched the www for other strip chart applications and found none as useful (and mostly free).?
However, please note that many, maybe most, of us are no longer using the sound card.? As my diagram which I sent out yesterday illustrated, using any of the SDR applications (my favorite has become SDR Console), we need SW link between that application and RSP.? For many of us, we use VB Cable.? Not that it's perfect, but.....? At LTO one long afternoon a couple of years ago, Terry and I sat down to sleuth out our data stream.? We caught VB Cable dropping chunks of data which plays havoc with additional data analysis.? Yes, it's a consumer product aimed at the audio world and we're attempting to use it for real science.? Reminding us.....that we are still amateurs.
Are there differences with RSP between porting directly from a sound card? to porting through a virtual audio cable application to RSP?? Many of us, myself included, no longer involve the sound card.? If I truly need a sound card, I use the Beringer UMC 202HD.??
In rather extensive testing and experimenting, I've discovered most of the PC and consumer directed sound cards, be they internal or external, do not perform to the advertised specifications.? One of the M-Audio external cards produced so much RFI I could not use it for radio astronomy or much of anything else.? Sound Blaster and many ASUS products are especially guilty of that.? I spent too much $$$ on Sound Blaster cards believing their published specs until I did some quantitative testing on the bench.? I finally went with Beringer which in some aspects exceeds and is true to their advertised specifications.? Buyer beware!
Dave - W?LEV
Hi Dave,
The detection method selected in RSP makes a big difference in how it processes
the input data, and as such, whether the output is linear with respect to its input.
--
Dave
On 5/22/25 10:44, W0LEV via wrote:
> I've confirmed a number of times using a number of professional spectrum
> analyzers that the signal generator is putting out what the knobs indicate.? The
> non-linearity is not due to the HP8648C.? My personal "target" for the
> non-linearity would be in order: 1)? VB Cable and? 2)? SkyPipe.
>
> I can test SkyPipe as I did the HP8648C, but VB Cable has no hooks other than
> links between applications within the PC.? Possibly Jim Sky could comment on the
> linearity of SkyPipe?
>
> I well realize the difference between white noise cal and my single signal
> tests.? But either will expose non-linearities in the system.? I have a known
> professional noise generator source which I could use which I used to calibrate
> the old RJ setup which employed only Radio SkyPips.? That was far easier and
> quite intuitive.? ?Personally I am not a fan of judging colors.? No two pairs of
> human eyes view subtle color differences and/or intensities identically.? But
> they sure make pleasing and attractive plots.? Just my two-cents.
>
> Any additional suggestions as to how best to sleuth the non-linearities I exposed?
>
> I have an SDRPlay RSP1.? Early on with our experiments with those at LTO (Little
> Thompson Observatory), here at home for me and Terry's (Dr. Terrance Bullette)
> experiments, we sadly discovered it was sorely prone to IMD and overload.
> That's why at LTO (and personally) we collectively placed the SDRPlay products
> on the shelf where they still reside.? I've only recently obtained an RX-888
> MKII, but, man, does it eat the 5-vdc power like a Class A amplifier at L-Band!
>
> Dave - W?LEV
>
>
>
> <>
>
> <>
>
> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>
> On Thu, May 22, 2025 at 2:00?AM Larry Dodd via <>
> <101science=[email protected] <mailto:[email protected]>> wrote:
>
>? ? ?Dave
>? ? ?The non-linearity isn¡¯t in SDR Console for sure. You¡¯re using a single
>? ? ?frequency stepped calibration where we use Jim Sky¡¯s stepped wide band noise
>? ? ?calibrator spanning ~8 MHz. If you have a known calibrated power meter you
>? ? ?could check your HP output. That would help to tell you where the
>? ? ?non-linearity lies.
>? ? ?Larry
>
>? ? ?_______________________
>
>
>
>? ? ?On Wed, May 21, 2025 at 9:48?PM W0LEV via <>
>? ? ?<davearea51a=[email protected] <mailto:[email protected]>> wrote:
>
>? ? ? ? ?I was intrigued by the calibration of the standard RJ setup.? While I do
>? ? ? ? ?not use that setup, I decided to measure what I use for other purposes,
>? ? ? ? ?including RJ.? So, have a read of the attachment.? I'm using the AirSpy
>? ? ? ? ?Discovery HF+ to test the linearity.? The system is diagrammed to start
>? ? ? ? ?and then, I ran an HP generator up by 10 dB steps ultimately into Radio
>? ? ? ? ?SkyPipe.? I was somewhat disappointed at the non-linear behavior of the
>? ? ? ? ?system.? Please have a read of the attachment.
>
>? ? ? ? ?CONCLUSION:? Yes, calibration is needed if linear response to the input
>? ? ? ? ?is required!!!
>
>? ? ? ? ?Dave - W?LEV*
>? ? ? ? ?*
>
>
>
>
> --
> *Dave - W?LEV
> *
>
>
>
|
Re: LINEARITY - MEASUREMENTS
Hi Dave,
The detection method selected in RSP makes a big difference in how it processes the input data, and as such, whether the output is linear with respect to its input.
--
Dave
toggle quoted message
Show quoted text
On 5/22/25 10:44, W0LEV via groups.io wrote: I've confirmed a number of times using a number of professional spectrum
analyzers that the signal generator is putting out what the knobs indicate. The
non-linearity is not due to the HP8648C. My personal "target" for the
non-linearity would be in order: 1) VB Cable and 2) SkyPipe.
I can test SkyPipe as I did the HP8648C, but VB Cable has no hooks other than
links between applications within the PC. Possibly Jim Sky could comment on the
linearity of SkyPipe?
I well realize the difference between white noise cal and my single signal
tests. But either will expose non-linearities in the system. I have a known
professional noise generator source which I could use which I used to calibrate
the old RJ setup which employed only Radio SkyPips. That was far easier and
quite intuitive. Personally I am not a fan of judging colors. No two pairs of
human eyes view subtle color differences and/or intensities identically. But
they sure make pleasing and attractive plots. Just my two-cents.
Any additional suggestions as to how best to sleuth the non-linearities I exposed?
I have an SDRPlay RSP1. Early on with our experiments with those at LTO (Little
Thompson Observatory), here at home for me and Terry's (Dr. Terrance Bullette)
experiments, we sadly discovered it was sorely prone to IMD and overload.
That's why at LTO (and personally) we collectively placed the SDRPlay products
on the shelf where they still reside. I've only recently obtained an RX-888
MKII, but, man, does it eat the 5-vdc power like a Class A amplifier at L-Band!
Dave - W?LEV
<>
Virus-free.www.avg.com
<>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
On Thu, May 22, 2025 at 2:00?AM Larry Dodd via groups.io <>
<101science@... <mailto:[email protected]>> wrote:
Dave
The non-linearity isn¡¯t in SDR Console for sure. You¡¯re using a single
frequency stepped calibration where we use Jim Sky¡¯s stepped wide band noise
calibrator spanning ~8 MHz. If you have a known calibrated power meter you
could check your HP output. That would help to tell you where the
non-linearity lies.
Larry
_______________________
On Wed, May 21, 2025 at 9:48?PM W0LEV via groups.io <>
<davearea51a@... <mailto:[email protected]>> wrote:
I was intrigued by the calibration of the standard RJ setup. While I do
not use that setup, I decided to measure what I use for other purposes,
including RJ. So, have a read of the attachment. I'm using the AirSpy
Discovery HF+ to test the linearity. The system is diagrammed to start
and then, I ran an HP generator up by 10 dB steps ultimately into Radio
SkyPipe. I was somewhat disappointed at the non-linear behavior of the
system. Please have a read of the attachment.
CONCLUSION: Yes, calibration is needed if linear response to the input
is required!!!
Dave - W?LEV*
*
--
*Dave - W?LEV
*
|
Re: Solar Activity reported by this group.
Jim: ? ? ?Incredible job! Thanks for accomplishing this and sharing with everyone.
On Thursday, May 22, 2025, 1:20 AM, Jim Sky <radiosky@...> wrote: Below is a chart showing reported solar activity by this group since it started.? This was done with ChatGPT's help and only includes new posts with an image and using keywords. It is just an approximate value.? The idea was to see if our activity on this group approximates the solar activity (using sunspot number because it was easy to get) and as an exercise for me to see if something might be done to facilitate archiving these curated reports.? ?All of the activity of this group was downloaded as a single 12 GB mbox file which was then used to produce a single filtered CSV file.? GPT then analyzed the CSV file and produced a python program the does the histogram.??
?
?
--
Jim Sky?
radiosky at radiosky dot com
|
Re: LINEARITY - MEASUREMENTS
I've confirmed a number of times using a number of professional spectrum? analyzers that the signal generator is putting out what the knobs indicate.? The non-linearity is not due to the HP8648C.? My personal "target" for the non-linearity would be in order: 1)? VB Cable and? 2)? SkyPipe.
I can test SkyPipe as I did the HP8648C, but VB Cable has no hooks other than links between applications within the PC.? Possibly Jim Sky could comment on the linearity of SkyPipe?
I well realize the difference between white noise cal and my single signal tests.? But either will expose non-linearities in the system.? I have a known professional noise generator source which I could use which I used to calibrate the old RJ setup which employed only Radio SkyPips.? That was far easier and quite intuitive. ? Personally I am not a fan of judging colors.? No two pairs of human eyes view subtle color differences and/or intensities identically.? But they sure make pleasing and attractive plots.? Just my two-cents.
Any additional suggestions as to how best to sleuth the non-linearities I exposed?
I have an SDRPlay RSP1.? Early on with our experiments with those at LTO (Little Thompson Observatory), here at home for me and Terry's (Dr. Terrance Bullette) experiments, we sadly discovered it was sorely prone to IMD and overload.? That's why at LTO (and personally) we collectively placed the SDRPlay products on the shelf where they still reside.? I've only recently obtained an RX-888 MKII, but, man, does it eat the 5-vdc power like a Class A amplifier at L-Band! ? ?
Dave - W?LEV?
?
Dave The non-linearity isn¡¯t in SDR Console for sure. You¡¯re using a single frequency stepped calibration where we use Jim Sky¡¯s stepped wide band noise calibrator spanning ~8 MHz. If you have a known calibrated power meter you could check your HP output. That would help to tell you where the non-linearity lies.
I was intrigued by the calibration of the standard RJ setup.? While I do not use that setup, I decided to measure what I use for other purposes, including RJ.? So, have a read of the attachment.? I'm using the AirSpy Discovery HF+ to test the linearity.? The system is diagrammed to start and then, I ran an HP generator up by 10 dB steps ultimately into Radio SkyPipe.? I was somewhat disappointed at the non-linear behavior of the system.? Please have a read of the attachment.
CONCLUSION:? Yes, calibration is needed if linear response to the input is required!!!
Dave - W?LEV
|
salvador aguirre
Andrew Mount
Larry Dodd
Chuck Higgins
Dave Typinski