SCGO Sudden Ionospheric Disturbance (SuperSID) System

Welcome to Starlight Cascade Observatory SuperSID System Project!
Near Yarker, Ontario, Canada. (44.22.39 N 76.45.47 W    151M Elevation)
Page Created: 2016 January 04
Page Updated: 2024 March 20

SCGO Home * Allsky1 * Allsky2 * RadioJove * SuperSID * Weather

SCGO Supersid Data (Updates hourly):

NAA- Cutler Maine 24.0KHz

NML- Lamoure North Dakota 25.2 KHz

NLK- Jim Creek Washington 24.8 KHz
SuperSID is an automated Sudden Ionospheric Disturbance 20-40 KHz radio receiver and antenna system located near Yarker (outside of Kingston) Ontario Canada.
It takes readings of VLF transmitting stations as they bounce off the ionosphere every 5 seconds, 24 hours a day.

  • NAA Cutler Maine is 9.5 deg longitude away east
  • NML Lamoure NorthDakota is 22.5 deg longitude away west
  • NLK Jim Creek Washington State is 46 deg longtitude away west

    It went operational in 2016 January, replacing an older SID system. We built a new 2m wide 24 loop antenna as well (24 gauge enamelled (insulated) wire on a 1" PVC frame with arms of 2m length. The circumference of this was 5.6m and we got24 turns out of the spool)

    Data is archived daily at Stanford University (California USA). It is available for viewing at:
    You can see all stations data from a complete day by using this link, customizing the date:

    In addition, you can see another station: Moore Observatory VLF Monitor for Space Weather and Solar Flares, daily images of NAA Cutler Maine USA

    24 loop, 2m antenna

    A peek inside the preamplifier/receiver
  • 24 loop, 2m antenna using enamelled (insulated) wire (about 22 guage) around pvc pipes.
  • The Supersid Receiver/preamplifier
  • SoundBlaster USB External Sound Card / Audio Adapter / Plug and Play / Microphone (Mic) In and 3.5mm Speaker Out from

  • On 2024February01 we switched back to the windows software supersid v1.2.2
    On 2023March05 new superSID code by Steve Berl was installed on a new build of Raspbian Bullseye 64bit OS. Multistation capability has returned as has data logging to the Stanford database.
    On 2021March10 the windows7 based software supersid v1.2.2 was replaced with a raspberry pi 3b and supersid code by Nathan Towne.
    So now we have a more reliable data logging device, that takes much less power and never gives a windows blue screen of death.
    Raspberry Pi 3 Model B is the earliest model of the third-generation Raspberry Pi. Quad Core 1.2GHz Broadcom BCM2837 64bit CPU 1GB RAM BCM43438 wireless LAN and Bluetooth Low Energy (BLE) on board 100 Base Ethernet 40-pin extended GPIO 4 USB 2 ports 4 Pole stereo output and composite video port Full size HDMI® CSI camera port for connecting a Raspberry Pi camera DSI display port for connecting a Raspberry Pi touchscreen display Micro SD port for loading your operating system and storing data

    The raspberry pi 3b unit.

    Pi & USB

  • Daffodil US01 USB External 7.1 Channel Sound Card / Audio Adapter / Plug and Play / Microphone (Mic) In and 3.5mm Speaker Out from

    NOAA GOES XRay Flux


    From 2016 January to 2021 March we used a windows 7 netbook running Supersid v1.2.2 for windows as a data logging software. We monitored three stations: NAA, NLK and NML. The software generated three .csv text data files NAA.csv, NLK.csv and NLM.csv. The data format in each file looked like this:
    # Site = SCO	
    # Contact =	
    # Country = Canada	
    # Longitude = -76.7631	
    # Latitude = 44.3775	
    # UTC_Offset = -5	
    # TimeZone = EST	
    # UTC_StartTime = 2016-07-22 00:00:00	
    # LogInterval =  5	
    # LogType =  filtered	
    # MonitorID = 9193	
    # SampleRate =  5	
    # StationID = NLK	
    # Frequency = 24800	
    2016-07-22 00:00:00	0.0465797139616
    2016-07-22 00:00:05	0.0457116274316
    2016-07-22 00:00:10	0.0448435409015
    With some custom linux bash scripting, R and python, and gnuplot, we generated three graphs every day:
    On 2021 March we successfully installed the supersid code written by Nathan Towne, but could not get all three stations reporting. Eventually with a lot of trial and error, we got the one station NAA reporting.
    Our current Header.txt config file consists of:
    # Site = SCO
    # Contact = xxxx
    # Longitude = -76.76
    # Latitude = 44.37
    # monitor_id = 9193
    # the integration time
    # loginterval = 5.0
    # stations =  NAA, NLK, NML
    # frequencies =  24000, 24800, 25200
    # group = naa, 23600, 24400, 1
    # transmitter = NAA, 24000, 2, f0, 24000, sig, 47.0, lambda f: np.exp(-((f - f0)/sig)**2/2)
    # group = group2, 24350, 25800, 2
    # transmitter  NLK, 24800.0, 2, f0, 24805.0, sig,  47.0, lambda f: np.exp(-((f - f0)/sig)**2/2)
    # transmitter  NML, 25200.0, 6, f0, 25200.0, sig, 49.0, f1, 
      f0+3.8*sig, f2, f0-4.0*sig, sig2, 0.38*sig, g, np.exp(-((f - f0)/sig)**2/2), 
      lambda f: g/(1+0.05/g) + 0.006*np.exp(-((f - (f1))/(sig2))**2/2) + 0.006*np.exp(-((f - (f2))/(sig2))**2/2)
    # transmitter = NML, 25200.0, 2, f0, 25200.0, sig, 72.0, lambda f: OrthPoly.silineshape((f - f0)/sig)**2
    The software starts on booting up using a cron job command: @reboot /home/pi/startsidmon &
    The command consists of:
    cd sidmon
    ./ -d plughw:CARD=Device  -lp 1

    The data syncs to a linux server once an hour : 1 * * * * /home/pi/0sync
    Which consists of: rsync -auvx /home/pi/sidmon/data/*.csv pi@ rsync -auvx /home/pi/sidmon/*.txt pi@ rsync -auvx /home/pi/sidmon/*.hist pi@

    The data folder has daily entries of .csv data like this:

    -rw-r--r-- 1 pi pi 457527 Nov 26 13:23 20211126Ch0.csv
    -rw-r--r-- 1 pi pi 609865 Nov 25 19:00 20211125Ch0.csv
    -rw-r--r-- 1 pi pi 618958 Nov 24 19:00 20211124Ch0.csv
    -rw-r--r-- 1 pi pi 614219 Nov 23 18:59 20211123Ch0.csv
    The data file looks like this:
    2021-11-25 23:59:47.96,199930.8,-414.1
    2021-11-25 23:59:53.58,228243.1,339.7
    2021-11-25 23:59:59.20,226557.2,-2386.6
    Which does appear to have three values.. only some of them are negative?


    Supersid is a newer multifrequency Sudden Ionospheric Disturbance detection system available from


               Station            Station     Frequency        Radiated
                 Site               ID          (kHz)            Power (kW)
      U.S. Navy                     
           Cutler, ME                NAA          24.0            1000
           Jim Creek, WA             NLK          24.8             250
           LaMoure, ND               NML          25.2             500

  • VLF Station List
  • SID Monitoring Station VLF List

    In the late 1940's, the U.S. Navy realized that they needed a high powered, low frequency, transmitter on the U.S. east coast which could broadcast to the North Atlantic and Arctic Oceans for communication with submarines. A radio transmitter was established in Cutler, Maine, for this purpose and it has been in operation since 1961. One fringe benefit is that this 1 million watt transmission at 24 kilohertz can be detected across the continental United States. The signal is very sensitive to the state of the Earth's ionosphere, because, at this frequency, it it is actually piped close to the surface of the Earth during the daytime. Several other VLF stations operate around the world, but Cutler provides the strongest daytime signal in this area.

    In this installation the radio signals are received by a directional loop antenna tuned to the Cutler station. The receiver amplifies and averages the signal with a time constant of about 10 seconds and its output is recorded

    Each day at 0 hours Coordinated Universal Time the images from the previous day are placed in the imagearchive, the latest complete plot is saved in the plot archive, and a new record is started.

    Each plot should show a signal which varies erratically during the night, but is smooth and steady during the day. The transition at sunrise and sunset is a very distinctive rise and fall pattern. When a flare occurs, the prompt X-ray emission from the Sun modifies the ionosphere and produces a sudden enhancement in the very low frequency 24 kilohertz radio signal from Cutler, Maine.

    Records of this type are kept by several amateur astronomers who coordinate their efforts through the American Association for Variable Star Observers.

    From Wikipedia: The D layer is the innermost layer, 60 km to 90 km above the surface of the Earth. Ionization here is due to Lyman series-alpha hydrogen radiation at a wavelength of 121.5 nanometre (nm) ionizing nitric oxide (NO). In addition, with high Solar activity hard X-rays (wavelength less than 1 nm) may ionize (N2, O2). During the night cosmic rays produce a residual amount of ionization. Recombination is high in the D layer, the net ionization effect is low, but loss of wave energy is great due to frequent collisions of the electrons (about ten collisions every msec). As a result high-frequency (HF) radio waves are not reflected by the D layer but suffer loss of energy therein. This is the main reason for absorption of HF radio waves, particularly at 10 MHz and below, with progressively smaller absorption as the frequency gets higher. The absorption is small at night and greatest about midday. The layer reduces greatly after sunset; a small part remains due to galactic cosmic rays. A common example of the D layer in action is the disappearance of distant AM broadcast band stations in the daytime.

    During solar proton events, ionization can reach unusually high levels in the D-region over high and polar latitudes. Such very rare events are known as Polar Cap Absorption (or PCA) events, because the increased ionization significantly enhances the absorption of radio signals passing through the region. In fact, absorption levels can increase by many tens of dB during intense events, which is enough to absorb most (if not all) transpolar HF radio signal transmissions. Such events typically last less than 24 to 48 hours.

    Resource Links:

  • Wikipedia entry on radio propogation:

    data logging win7 notebook - replaced with a raspberry pi 3b
    on 2021march10th.
  • Supersid System Log

  • 2024Feb23 - modified processing and graph generating code so that each station is now customized. Checking stanford data archive, the quality of the NAA (Maine) and NLK (Washington State) are high but NMK (North Dakota) is not.. mostly noise.
  • On 2024February01 we switched back to the windows software supersid v1.2.2
  • 2024Jan18 - not getting clear signals for some weeks. working on developing a troubleshooting checklist up to and including a wipe and reinstall of raspberry pi OS and supersid softwre.
  • 2023March13 - added station NLK Jim Creek Washington 24.8 KHz.
  • 2023March05 - successfuly configured for stations NAA Maine and NML North Dakota. still only using local bash scripts to generate and annotate plots from .csv data on an hourly basis.
  • 2023March04 - turned system off, removed sd card from raspberry pi and started over. Installed new raspbian bullseye 64bit OS with GUI. Download and installed code and started to configure.
  • 20220418 - added backend gnuplot code to pull out NLK - Jim Creek Washington 24.8KHz data
  • 20210418 - wrote code to generate a graph every hours as the supersid data comes in from the raspberry pi. The data has its headers stripped, formatted a bit and run through gnuplot. Textual annotations are made with imagemagick. This is then uploaded to this website.
  • 20210325 - various configurations leave us with a data file that we do not understand the values in the data. The old windows supersid data logger was quite straightforward.
  • 20210310 - finally. removed the very old win7 netbook and installed the new supersidpi this morning around 09:00. Now working on code to get the data from the pi to the file server and then to figure out what code can generate graphs.
  • 20210223 - SUCCESS! Installed and successfully ran Nathan Towne Python code SIDMON on a raspberry Pi model 3B. Now commissioning with hopefully a swap with the windows 7 based platform in a few days.
  • 20200525 - reverted back to windows7 netbook and supersid v1.2.2
  • 20200216 - still out of service.. working to get the python scripts up and running for data logging and processing.
  • 20200104 - replaced netbook with raspberry pi model 3b, usb audio. working on configuration, data processing, image generation and data management..
  • 20190414 - windows 10 audio will simply not work. Not with the laptop internal audio jack, not with a USB sound adapter, nothing! Pulled the supsersid from the win10 laptop and reconnected it to the old Win7 notebook that it used to be connected to, but this time on a wired network. We should see the first data April 15th after 20:00EDT
  • 20190411 - signal strength is low to very low to superlow. will need to inspect power and output sound
  • 20190407 - moved antenna, connected supersid received to longmire win10 lenovo laptop, usb for power, audio plug for signal. Only lenovoT420 audio jack does not accept standard mic plugs. only combo plugs. arrg! ordered USB sound adapter, should arrive and be functional and in commission by wednesday evening.
  • 20190210 - OUT OF COMMISSION - hardware keeps crashing, rebooting, not detecting a boot drive. Many times over. Remove from receiver. Look to rebuild a data logging system using a raspberry pi and python scripts.
  • 20181111 - data logging netbook 250GB sata spinning cloned and replaced with 120GB SSD.
  • 20180611 - windows 7 32bit netbook intel atom N570 @1.66GHz, 2GB RAM with supersid software installed in c:\supersid. Signal power tends to drop over time until software reset. reset today at 14:30 local EDT Located well away from the house and connected via wifi and wifi extender.
  • 20180316 - changed station name back to SCGO - broke a lot of the scripts.
  • 20180309 - changed station name from SCGO to StarlightCascadeGardensand ObservatoryYarkerOntarioCanada
  • 20171215 - looking at implementing a raspberry pi data collection system instead of a netbook
  • 20171121 - supersid offline since 2017 Nov 16 when it dropped off the network. Hopefully will see some data tonight after 00:00 UT
  • 20170330 - imagearchive broken... rewrote code today
  • 20170209 - working well for many months now, with antenna 30m away from the house, out in the vegetable garden and the data logging computer in the greenhouse, 10m away from the antenna.
  • 20161108 - still working out kinks in the processing code
  • 20161020 - Correct data processing error.. have been processing the same data into graphs since 20161004!
  • 20160805 - We've been losing wifi connectivity with the SuperSID system since it moved out into the back gardens. A WiFi extender was installed yesterday and we are starting to get data again! Y axis scale moved from max 50 to 100
  • 20160715 - moved supersid antenna out to garden, well away from house, linked with a 50' RG58 cable to the netbook linked with wifi
  • 20160302 - successfully uploading data to stanford for a week now. Using only 3 stations and even then we do not appear to be picking up North Dakota or Washington State. This may change when we move the antenna out of the RF shadow of the house later in the spring, so we will keep those two stations up for now.
  • 20160201 - moved the antenna and computer outside onto a covered deck, antenna with a clear view of the eastern horizon.
  • 20160104 - built the loop antenna with 24 gauge enamelled (insulated) wire on a 1" PVC frame with arms of 2m length. The circumference of this was 5.6m and we got 24 turns out of the spool of wire we had. This was connected to a terminal block on the mast. an RG58 coax cable attached to the terminal block at one end and the supersid receiver on the other. The Supersid receiver is a newer model, powered by a 5vdc USB plug, with an audio jack to plug into a computer system. The sound card must support 96KHz sampling as 44 KHz does not get good results (we tried). Software was provided (supersid 1.2.2) and takes a reading every 5 seconds for 24 hours and then saves out the data to file. This does not show an x-axis time chart but rather an x-axis frequency chart, with intensity up the y-axis.