sigidwiki

2e0wes

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hey guys, is there anything else out there besides this, im comparing the pictures on the website to the waterfall on my sdruno, and there not even close. is it a case of the pattern will be similar, but the colours will vary depending on the software your using, or are the colours, iso colours? thanks in advance.
 

ka3jjz

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That's quite possible. There isn't a standard in the color patterns, per se. While the sigidwiki is the most comprehensive, there are other sites with similar data. From our digital decoding FAQ.. See section 4 of


Mike
 

sadatoni

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There's one I pick up quite often that isn't on sigidwiki. It looks like it's likely OTH, but I don't know for sure.

WhatIsThis.jpg
 

Token

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There's one I pick up quite often that isn't on sigidwiki. It looks like it's likely OTH, but I don't know for sure.

View attachment 89514

Yes, it is an OTHR. Which one it is you cannot know from a single screen shot like that. It is most likely either the Australian JORN or the US ROTHR, however there are a couple of other possibilities also. Both JORN and US ROTHR may have pre beeps before the FMCW bursts, but they can also transmit without the pre-beep, like other OTHRs. If you hear a single pre-beep it can be either the JORN or US ROTHR (normally JORN), and that pretty much eliminates other sources. If you hear a pre-beep with three tones then it is the US ROTHR.


To reitierate, burst as you show can be one of several different OTHR options, most probably JORN or US ROTHR. Such bursts with single pre-beep on the center frequency either JORN or US ROTHR, most probably JORN. Pre-beep with more than one segment, US ROTHR.

Also keep in mind that while the sigidwiki is a good resource, it is not without error and is far from exhaustive. There are many signals you will not find on that resource, and some data is wrong, for example the listed frequency range of JORN is not right.

Pay less attention to the pictures on sigidwiki and more attention to the audio recordings. The software used, sample rates, write speeds, sampled bandwidths, colors, signal strengths, etc, etc, can all change the image a lot. But the sound is less variable.

T!
 

sadatoni

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This has just the one audio sound, no pre-burst nor after burst. It can show up in up several close frequencies. Doesn't sound like JORN (except for one of it's frequency patterns), nor ROTHR. I'll have to record it next time I come across it.

Edit: I take that back - it is very similar to ROTHR. Not as many different speeds.
 
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Token

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This has just the one audio sound, no pre-burst nor after burst. It can show up in up several close frequencies. Doesn't sound like JORN (except for one of it's frequency patterns), nor ROTHR. I'll have to record it next time I come across it.

Edit: I take that back - it is very similar to ROTHR. Not as many different speeds.
These radars are adaptable and change often. By that I mean, don't get hung up on it sounding exactly like the examples on sigidwiki. The examples there are not every possible mode of the radars, there are dozens, if not hundreds, of combinations of bandwidth, chirp rate, and rep rate for each of these radars. ROTHR (and JORN) may not send different speeds for extended periods of time, every TX on a given frequency for several minutes might be the same waveform. Or it might change to a new one every transmission.

T!
 
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