No, Tyler did great. Perhaps he can add comments on the youtube videos that provide this additional information. Videos like this take talent, or time, or both. It always helps to story-board them before . When I do cloak videos, I story board first, narrative second, then raw video --which then gets edited and digitally spliced. 73 Chip W1YW
To achieve the level of graphic resolution you see, may just look 'natural' to anyone viewing the video. It is not natural at all. There are about 25 custom settings that have to be assigned correctly to achieve those results. Most SDR systems are maladjusted and look really bad. For example, bin-width, frames per second, refresh rates, panadapter averaging, water-fall averaging, scaling and spans along with the 'colors' and so on you use are very flexible. You can see how I do mine, even though some resolution was lost in the youtube compression even at 1080HD, some are just esthetic as well...not a correct or incorrect... By the way, my RX tests show the noise floor at -150dB, so this things is wild, no IF, no mixers, nothing. Just total RF bliss, it makes my traditional rigs look like Model T antique by comparison. -We did not even talk about the transmitter yet (it stands alone from all Amateur Radios ever made, with Adaptive Pre Distortion I can apply a correction to my signal that drops my IMD3 to -75dB from -30dB) Good by Splatter. I have made videos where I completely destroy the beautiful graphics to show that the customized ability is the SDR's best and worst parts. It took months of experiments to get this setup. A lot of people want to know about it, so rather then emails and on the air talks, videos again I feel can communicate more info in 5 to 10mins well edited. Thanks Chip!
Thanks for the great post, Tyler .... I've heard OTH RADAR signals (or what I thought might be them) many times, but never looked closely at them before. I think I listened for a while and chalked this one up to another one of those "Outer Limits" tones (The Original Series), since that's what it sounds like if your BFO is set too high (or low). I am very curious about how they work, since I've worked for a long time <garble> years ago on conventional shore-based air-surveillance RADARs. Learning is (still) fun! Thanks again!
I assume the time from the center to each individual signal allows a greater level of reliability of the outgoing signal due to the sheer number? It allows for fading on the return trip too?
Not sure exactly what you are asking here. But, if you are refering to the total bandwidth of the signal, greater bandwidth generally equates to better resolution. Bandwidth, in combination to pulse repetition/pulse interval (inverse) allow for greater target resolution in radar applications, depending on the desired target. Jim
Now that comments are disabled on your channel, it is easy to take the comments and suggestions from those that really understand what is going on and simply ascribe them to yourself without sharing any credit, as you have done on the recently re-titled/updated CMOR video, or the wrongly-identified CODAR video that you have since removed. I understand that you're trying to portray yourself as an OTH-R expert and that you want to build an audience, but this shows two things: 1) You're uncomfortable with criticism and sharing credit 2) You're willing to live with misinformation if it furthers building your audience Experts welcome criticism because it is only in the forge of disagreement and the challenging of ideas that the truth can be forged. It is obvious that you don't welcome that criticism. I appreciate the quality of the videos and your willingness to do them, but I definitely won't be helping/making suggestions any longer, and I suspect that other experts will let you hoist yourself with your own petard as well.
As I have mentioned to others, I would ask you to not use the term "Woodpecker" for current HF radars. The real Woodpecker (Duga) was unique, unmistakable, and now gone over three decades ago. No current radar comes close to the disruption and aural pain it inflicted. There are many types of HF radar, many OTH Air Surveillance HF radars, most are not Russian, and it is confusing and inappropriate to use the term 'Woodpecker" since it is not descriptive nor accurate. bill.
Basically, do your research before publication. That mantra is a stalwart philosophy in modern day academia and industry.
I assume you receive a returning signal with some time difference between transmit timing. The bandwidth resolution helps accuracy?
I want to thank everyone who has offered suggestions and info on the signal, as to N1SZ he and I spoke off this thread, a few days ago, I wrote him and thanked him personally for his help and am looking for ways to give credit where it is due. I removed the mislabeled video as not to have misleading info up there, why keep up a mislabeled video??? When it gets re-posted N1SZ as we have spoken in privet was going to be brought up for his help... All this was in privet communications. I can see how disabling comments can be interpreted in a negative light, I just thought it made a cleaner video with less clutter, but all those comments are restored, I did not want to have any misunderstanding there and sorry if by disabling them it somehow came across like that. Thanks again for all the help. 73
Great question. Here is somewhat of a crappy answer: It will depend on the type of receiver technology used. Clearly, greater bandwidth will help with resolution in most cases. Timing is always critical in pulse transmission (PRF/PRI) and the quality of the returned target signal. I may have failed to mention, modulation technique is just as important. Phase interferometry is a preferred technique in this received application. IQ analysis of the signal is very instrumental in determining targets from clutter. Jim
Always glad to help in any way possible. Our license is just that, a license to keep learning....... Jim
I also failed to mention that as far back as the DUGA, many HF Radar signals have had pseudorandom (binary and other) signals encoded into their transmissions to avoid spoofing. - (cited) multiple sources.. including Wikipedia.
Thanks. I worked on Marine radar for 10 years. I was putting itin the language I understood. An off the wall comment, the transmit signal looks a lot like an Orthogonal pattern.
