more satellite with rtl-sdr, wxtoimg, ...., link exploration

removed sdr# and mono because I am going to use GQRX

https://www.scivision.dev/sdr-sharp-ubuntu/   (Scientific Computing | SciVision)  --- reverse this....


5:31 / 30:13
APT Weather Satellite Reception with RTL-SDR, SDR#, WXtoImg, and Orbitron
https://www.youtube.com/watch?v=drliNzdtQZw

figure out how to make this work with jackaudio... on linux

https://gqrx.dk/doc/streaming-audio-over-udp

wxtoimg

stream raw audio over UDP, Record Audio

https://lucasteske.dev/2016/02/recording-noaa-apt-signals-with-gqrx-and-rtl-sdr-on-linux/

try jack audio:

https://jackaudio.org/api/index.html
https://qjackctl.sourceforge.io/qjackctl-index.html#Intro

Decoding NOAA weather satellite with RTL-SDR GQRX and WXtoimg -Tutorial
https://www.youtube.com/watch?v=bCGT6GCRjuM



https://noaa-apt.mbernardi.com.ar/


https://leshamilton.co.uk/wxtoimg.htm


https://www.rtl-sdr.com/new-noaa-apt-image-decoder/

Perhaps build a QFH antenna:

https://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weather-satellite-images/


extra:

More info on history of amateur satellites and how to track them. bookmarked time for how to track them.
https://www.youtube.com/watch?v=qgc9LxWfsxY&t=55m17s

https://gqrx.dk/doc/streaming-audio-over-udp

https://www.rtl-sdr.com/a-tutorial-on-decoding-noaa-and-meteor-m2-weather-satellite-images-in-ubuntu/

Edit Sept 23rd, perhaps PulseAudio will help connect WxToImg and gqrx??
https://oz9aec.net/radios/gnu-radio/gqrx-and-pulseaudio

The Things Network links

 The Things Network Part One 

https://www.youtube.com/watch?v=pAjknWIxoVA

The Things Network Part Two

https://www.youtube.com/watch?v=8bl0pmnpK_8


https://github.com/TheThingsNetwork

Is my perception that Gremlin can query over multiple machines correct?

Brent Shambaugh  7:42 PM
From my understanding Gremlin allows for the querying over a "giant global graph" like structure using property graphs. This means that the data can be distributed amongst machines and little gremlins can run everywhere. (https://web.archive.org/web/20160713021037/http://dig.csail.mit.edu/breadcrumbs/node/215)
Brent Shambaugh  7:51 PM
ahh okay, I'm satisfied: https://docs.janusgraph.org/storage-backend/cassandra/

Trying out IEEE754 to build a 32 byte message that can be cryptographically signed.

 Decimal to IEEE 754 Floating Point Representation -- https://www.youtube.com/watch?v=faTGTgid8Uc ... I am watching this so that I can convert a floating point number to a 32 byte type uint8_t array that can be signed by a private key, and verified using a uint8_t public key. 

http://cstl-csm.semo.edu/xzhang/Class%20Folder/CS280/Workbook_HTML/FLOATING_tut.htm

Big Endian and Little Endian
https://chortle.ccsu.edu/AssemblyTutorial/Chapter-15/ass15_3.html


"Array Element Storage

As you might remember from Day 8, the elements of an array are stored in sequential memory locations with the first element in the lowest address. Subsequent array elements (thos with an index greater than 0) are stored in higher addresses. How much higher depends on the array's data type
(char, int, float, and so forth)" -- pg. 203 , Sam's Teach yourself C in 21 Days, Sixth Edition by Bradley Jones and Peter Aitken

Convert Binary to Decimal
https://www.rapidtables.com/convert/number/binary-to-decimal.html

How to return multiple values from a function in C or C++? 

https://www.geeksforgeeks.org/how-to-return-multiple-values-from-a-function-in-c-or-cpp/

This looks like an end result of what I am trying to create:
Program for conversion of 32 Bits Single Precision IEEE 754 Floating Point Representation

https://www.geeksforgeeks.org/program-for-conversion-of-32-bits-single-precision-ieee-754-floating-point-representation/

goting back:

IEEE 754 Floating Point Representation to its Decimal Equivalent

https://www.youtube.com/watch?v=LXF-wcoeT0o

Convert Float to Hex (notes)

How to convert float to hex?
https://bytes.com/topic/c/answers/219928-how-convert-float-hex

https://en.wikipedia.org/wiki/Integer_(computer_science)

a completed solution of a int to hex:
https://www.geeksforgeeks.org/program-decimal-hexadecimal-conversion/

https://gist.github.com/bshambaugh/8788cdb6644e235c510dc7cb2f4b3786

https://www.baeldung.com/java-byte-arrays-hex-strings

compare to:
https://www.scadacore.com/tools/programming-calculators/online-hex-converter/

But you really want:

Tutorial: Floating-Point Binary

http://cstl-csm.semo.edu/xzhang/Class%20Folder/CS280/Workbook_HTML/FLOATING_tut.htm

https://en.wikipedia.org/wiki/Single-precision_floating-point_format

method:

Decimal to IEEE 754 Floating Point Representation
https://www.youtube.com/watch?v=8afbTaA-gOQ

(compare: https://www.geeksforgeeks.org/program-for-conversion-of-32-bits-single-precision-ieee-754-floating-point-representation/),(https://blogs.nvidia.com/blog/2019/11/15/whats-the-difference-between-single-double-multi-and-mixed-precision-computing/)

misc:

https://stackoverflow.com/questions/37538/how-do-i-determine-the-size-of-my-array-in-c
https://stackoverflow.com/questions/34844003/changing-array-inside-function-in-c/34844835

See Discrete Mathematics, 7th ed, page 231.

ASR6501 for CubeCell

Link between CubeCell Module (HTCC-AB01) and ASR6501.
https://github.com/HelTecAutomation/ASR650x-Arduino

Specs provided on Amazon:

https://www.amazon.com/Heltec-ASR650x-ASR6501-CubeCell-Development/dp/B0813CYL8D

leads to:

https://www.electronicproducts.com/a-look-at-cortex-m0-and-m0-microcontrollers/
https://www.microchip.com/wwwproducts/en/ATSAML21J18B

I also found ASR6501 in a code repository:

https://www.electrodragon.com/w/ASR6501

https://github.com/asrlora/alios-asr-lora/blob/master/board/asr6501/board.h

Talking to someone tells me that since the CubeCell implements I2C in hardware then my I2C issues with getting the public key and 32 byte numbers back are in software.

On page 375 of https://www.microchip.com/wwwproducts/en/ATSAML21J18B:
Support of 100kHz and 400kHz, 1MHz and 3.4MHz I2C mode low system clock frequencies


 Wire.setClock(400000);

Getting Data from Satellite

https://www.rtl-sdr.com/tag/wxtoimg/

mentions:
https://wxtoimgrestored.xyz/beta/

mentions a virtual audio cable, here is a search result:
https://www.onetransistor.eu/2017/10/virtual-audio-cable-in-linux-ubuntu.html

https://jackaudio.org/

(edit: see more: https://www.reddit.com/r/RTLSDR/comments/6d0rff/piping_audio_to_another_program_with_gqrx/ ) , https://qjackctl.sourceforge.io/qjackctl-index.html#Intro )

the guy on the wxtoimg page said he used vb-audio for his virtual audio cable.
https://www.vb-audio.com/

Added. Jack Audio is also here:
https://www.dxzone.com/catalog/Software/Linux/