32 line HAARP transmission decoding results

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32 line HAARP transmission decoding results

Postby smeezekitty » Mon Oct 31, 2022 8:26 am

These are the best results I could get from the VE9OHM/Amanda's HAARP NBTVA transmissions. It seems like the sync pulses were often corrupted and the lack of high-frequency response causes a lack of contrast

https://www.youtube.com/watch?v=nrtCbefBrHk
https://www.youtube.com/watch?v=xXZEecYmzTY
https://ghostsintheairglow.space/
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Re: 32 line HAARP transmission decoding results

Postby Steve Anderson » Mon Oct 31, 2022 11:11 pm

If it is possible, can you post the original off-air signals, i.e. simply the original audio you received. The resultant waveforms may give a clue as to what was amiss. Also if the original files that were transmitted would allow some comparison. i.e. what did HAARP try to transmit? The format? How many lines, frame rate. and the overall format used. I'm asking these questions as to assume that it's 'standard NBTV' may be erroneous...

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Re: 32 line HAARP transmission decoding results

Postby smeezekitty » Tue Nov 01, 2022 7:34 am

Here is an example of one the off-air received files. I don't have (although I didn't ask for) permission to post the original .wav files but here is a rough comparison. There seemed to be a lot of noise, lack of low frequency response and some ringing on transients (i.e. the sync pulses). I am not sure why the original .wav file amplitude is so low

waveform_compare.JPG


It should be approximately NBTVA standard, at least to the point of FreeNBTV generated using the preset. 32 lines, 12.5FPS
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haarp_rx_waveform.wav
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Re: 32 line HAARP transmission decoding results

Postby Steve Anderson » Tue Nov 01, 2022 4:33 pm

The original waveform looks 'OK', though it's a bit low I guess it's of no real issue. If it were recorded at 16-bits, there's around 12-13 bits used, so no problem with noise from the source. It should be adequate.

You can hear the distinctive NBTV 400Hz buried amongst the noise, which being AM and a long(ish) distance is no surprise. The rather 'spikey' nature of the sync pulses makes me wonder if some form of pre-emphasis has been applied? Or perhaps a 'feature' of the receiver used.

An unknown is what tests have been tried locally to the transmitter to ensure it is radiating a valid signal? Just a few km would be enough to asses the signal integrity is as desired. All that would require would be a receiver plus antenna, an oscilloscope, a PC/laptop to record results and a vehicle, maybe if needed an inverter or small generator to provide 120/220V power. RF guys refer to this as a 'field survey'.

That's where I would start...not forgetting that NBTV does require a very good LF performance. Again, an unknown is what are the modulation specifications of the transmitter...

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Re: 32 line HAARP transmission decoding results

Postby smeezekitty » Wed Nov 02, 2022 6:23 am

You can hear the distinctive NBTV 400Hz buried amongst the noise, which being AM and a long(ish) distance is no surprise. The rather 'spikey' nature of the sync pulses makes me wonder if some form of pre-emphasis has been applied? Or perhaps a 'feature' of the receiver used.


That particular clip was made using an RTL-SDR which only has 8-bits of dynamic range which could cause some of the problem. If anyone is interested, I included the (fairly large) I/Q file which can be loaded into HDSDR so others can experiment with filters and receiver options (tune to +110Khz)

I found (I originally misplaced the file) the 2 min clip which was made with a traditional receiver (Yaesu FT-891) made during a different broadcast which has less noise and fading but is frequency limited by the radio's 6.5KHz AM filter and contains 60Hz ripple from the recording equipment (I notched the 60Hz out in the video). The syncs are still spikey (albeit less so), probably due to the limited bandwidth. It was broadcast 4 times but I was only able to capture these two clips.

I think FM might be a better way to send NBTVA standard video due to it's better low frequency performance? (technically DC I think?)

An unknown is what tests have been tried locally to the transmitter to ensure it is radiating a valid signal? Just a few km would be enough to asses the signal integrity is as desired. All that would require would be a receiver plus antenna, an oscilloscope, a PC/laptop to record results and a vehicle, maybe if needed an inverter or small generator to provide 120/220V power. RF guys refer to this as a 'field survey'.

That's where I would start...not forgetting that NBTV does require a very good LF performance. Again, an unknown is what are the modulation specifications of the transmitter...

This is all unknown to me as well. I helped Amanda with the NBTV part but didn't work on the transmitting portion whatsoever and it is her project.
Attachments
HDSDR_20221025_163556Z_RF.zip
(37.53 MiB) Downloaded 101 times
2min_nbtv.wav
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Last edited by smeezekitty on Wed Nov 02, 2022 7:55 am, edited 1 time in total.
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Re: 32 line HAARP transmission decoding results

Postby M3DVQ » Wed Nov 02, 2022 7:42 am

It looks like images of the HAARP antenna array, a person waving, and a wind turbine to me :)
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Re: 32 line HAARP transmission decoding results

Postby smeezekitty » Wed Nov 02, 2022 10:13 am

M3DVQ wrote:It looks like images of the HAARP antenna array, a person waving, and a wind turbine to me :)

A pan of the HAARP array is definitely included. The "wind turbine" seems to be some sort of spinning antenna (a radar of some sort? idk) and I'm not 100% sure about the another parts. I don't have the original videos; just some of the generated NBTV and the off-air recordings
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Re: 32 line HAARP transmission decoding results

Postby Steve Anderson » Wed Nov 02, 2022 12:27 pm

smeezekitty wrote:I think FM might be a better way to send NBTVA standard video due to it's better low frequency performance? (technically DC I think?)

As a generalisation that's true, but as ever there are compromises to be made. We could go into a discussion about this, but the HAARP transmitter is AM so that's that. A sub-carrier could be used to achieve FM-type results as per SSTV but at this stage I don't know the transmitters capability in terms of modulation frequency response, it would need to be beyond 20kHz to accommodate a sub-carrier that could convey a 10kHz NBTV signal.

In addition the receiver would need a similar response, I doubt they exist unless designed and built specifically for this application.

Without the transmitters specifications, esp. modulation capabilities, it's somewhat of an uphill battle...

Steve A.

In addition to the above, the antenna array/RF distribution arrangements may also conspire to limit the modulation bandwidth. With it's intended application the array may have a very narrow bandwidth, we just don't know.

...later, I've seen a note (somewhere) that HAARPs modulation bandwidth is up to 100kHz, that would need verification...
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Re: 32 line HAARP transmission decoding results

Postby Harry Dalek » Thu Nov 03, 2022 7:52 pm

I think he had set the bandwidth on SDR program to low ,i have used those for weather Satellites in the past i see it set to low i saw 1khz on the site and another a bit lower ,i think they were NBTV as he was using it as play back .
I was also thinking i have tried transmitting NBTV via the atmosphere and got better results .
FM NBTV works better than Am on record recording PWM even better ,perhaps try correct bandwidth and experiment with different modes ,get no where with 1KHz bandwidth
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Re: 32 line HAARP transmission decoding results

Postby smeezekitty » Sat Nov 12, 2022 5:59 pm

Harry Dalek wrote:I think he had set the bandwidth on SDR program to low ,i have used those for weather Satellites in the past i see it set to low i saw 1khz on the site and another a bit lower ,i think they were NBTV as he was using it as play back .
I was also thinking i have tried transmitting NBTV via the atmosphere and got better results .
FM NBTV works better than Am on record recording PWM even better ,perhaps try correct bandwidth and experiment with different modes ,get no where with 1KHz bandwidth

I included the HDSDR I/Q files so you can experiment, but the bandwidth drops off fast. Tune to +110KHz
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