Can we detect Sprite and Blue Jets with the GRAVES Radar ? - Possiamo rilevare gli Sprite ed i Blue Jet con il radar GRAVES ?

Dopo avere passato ore a ricevere le tracce Doppler del Radar GRAVES ho scoperto una categoria di segnali che non sembrano riconducibili ad aerei , meteoriti o satelliti. Durano pochi secondi, gli echi sono molto forti, l’effetto Doppler si muove casualmente entro una banda di 200Hz circa e l’ampiezza varia molto rapidamente come nel video proposto.

After spending hours in receiving Doppler traces of the GRAVES Radar, I discovered a class of signals that doesn’t look connected to airplanes , meteors or satellites . They last only some seconds , the echoes are very high , the Doppler moves erratically within a 200 Hz bandwidth and the amplitude change very fast as in the proposed video .

L’unica teoria che mi viene in mente al momento è una repentina e breve ionizzazione di una parte del percorso tra il trasmettitore del radar ed il ricevitore che rifletta il segnale del radar comportandosi come un oggetto metallico . Questo potrebbe forse generarsi da parte di fenomeni quali gli “Sprites” od i “Blue Jets”.Solo una teoria che può essere confermata o meno correlando questi echi con altri mezzi per rivelare gli “Sprites” od i  “Blue Jets”, come i sistemi ottici e le ricezioni in VLF od altre bande RF .Se confermata , sarebbe un’ ulteriore modo per rivelare gli “Sprites” od i “Blue Jets”. Se non confermata , una delle tante teorie errate da parte mia …. Il file audio puo' essere sentito a questo collegamento : Audio mp3 Lo spettrogramma dell' eco e' visibile nella figura seguente (il verme rosso ...).

The only theory I have at the moment is a sudden and brief ionization of part of the path between the radar TX and the RX that reflects the radar beam like a metallic object . This could be generated perhaps from “Sprites” or “Blue Jets” phenomena.Only a theory that has to be confirmed or not correlating this echo events with other way to detect “Sprites” or “Blue Jets” , like optical or VLF or other RF bands receptions of signals from them . If confirmed , is another way to detect “Sprites” or “Blue Jets”. If not confirmed , another of many wrong theories from my side … Audio file can be heard here : Audio mp3 Spectrogram of the echo in the following picture ( the red worm ... )

Following a more expanded analysis in frequency and time, that shows the erratic shape of the echo together with the tropospheric signal of the radar and three airplanes echoes .

If you click to enlarge the picture , yuo can see also the trace of a meteor just before the strange echo.

Does the meteor triggered the event or they was only at the same time and not correlated ? 

Or the "meteor" is the sprite spark and then the other trace is the ionization cloud propagation ? 

Need more events to study ...

Just received a thread from the VLF Group where I have also sent this post .

Il looks that the concept is validated and so not peregrine ...

Hi Claudio,

I have captured many sprites reflecting off of VHF scatter.  I wrote a preliminary paper with various specimens which can be found here:   http://www.heliotown.com/Radio_Sprites_Ashcraft.html

Since writing that paper I have collected many more specimens.

The sprite research community has not looked into this very much. I believe the VHF scatter gives a picture of the plasma envelope of the sprite and ionisation.

There are also halo, jet and elve VHF scatter captures.

Thomas Ashcraft  -  Heliotown  -  New Mexico

Many VLF sprite specimens here:  http://www.heliotown.com/Catalog_Transient_Luminous_Events.html
.................................................................................................................................................................
Hi again Claudio,

Here is another specimen recorded by list member Kevin Palivec. It is a gigantic jet reflecting scatter off the US Space Fence radar at 217 MHz. A tremendous specimen. ( Too bad the space fence has been decommissioned)

http://palivec.us/~malathar/temp/Hawley-tx-9-26-2012-053303UT.mov

Also, please know how much I appreciate my E202 radio that you make. All my sprites the past two years were recorded with that radio and a Marconi long wire.

Thomas
...................................................................................................................................................................
Hi Thomas ,

thank you for all your precious reference and info ,
that I have added again to the publication of the blog .

I hope not to bother you regarding some questions about :

- Could you please specify what method of demodulation and BW you
have used while recording the echoes in VHF ? ( I have used CW and BW +/-
200 Hz )

- Could you describe the optical and RF setup of this link :

http://www.heliotown.com/FBs20110417_074250utAshcraft.mp4

Thank you for your kind words related to the E202 .

The design is from Renato Romero .

I helped him in spreading around to help the dissemination of the VLF-
ELF-ULF culture :

http://www.vlf.it/romero2/explorer-e202.html

The same is for the ICS101 :

http://www.comsistel.com/product.php?id_product=15

http://www.vlf.it/romero3/ics101.html

Thank you and kind regards .

Claudio 
...................................................................................................................................................................
Hi Claudio .

Optical : Camera is similar to Watec 902-H analog video camera. I split
the video feed using a video distribution amp into two separate feeds.
One video feed goes into a Sentinel capture box. This capture box is not
available publicly but the capture box works essentially like UFOCapture
software which triggers on flashes.

The second video feed goes into a Canopus ADVC-55 (analog to digital
video converter) which has two audio inputs for my two ICOM PCR 1000
radios. ( In this case of the fireball one radio was tuned to 83.250 MHz
CW and the other was tuned to 61.250 MHz CW.)
The merged audio/video then runs into an IMAC running old iMovie6
software which records continuous video/audio through the night into a
large hard drive. I extract the significant events into specimen movies
and dump the bulk of the night's recording to clear space for the next
night's recording.

I think this system I use with a Mac can be duplicated on a PC.

I have found that old iMovie6 software can split files into 10 minute 2
GB file sizes whereas newer movie software makes one single file which
might be 150 GB is size which can be problematic to work with.

Feel free to ask any further questions as I am just describing the basic
system.

Thomas