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Re: [IRCA] Morning TP Methodology?



Thanks Guy. I agree that this is a very effective method for top of the hour ID searches. However, here I'm reviewing up to 90 minutes of files every day, and SDR technology is capable of more than clicking on a playback bar when reviewing potential DX over that much time.

I mentioned the DXFishbarrel, which uses an older SDR, and which can be recorded as a video from screen. An initial analysis of conditions changing over 90 minutes can take very little time. See http://www3.telus.net/public/shallpat/4all/FBarrelSept2018.avi for a minute long analysis of this morning. (yellow, orange and red on the color bars indicate signals with audio) The Japanese big guns are there of course, but at 13:37UT, 1422 pops up for less than a minute in the original recording with a woman in Japanese at good level: http://www3.telus.net/public/shallpat/4all/1422_20180922_1337.wav And then, for a quick fade up and down for 30 seconds or so, check out 1701kHz at 13:44UT http://www3.telus.net/public/shallpat/4all/1701_20180922_1344.wav (Brisvaani judging by the 30Hz offset?)

Those were found with that minute long scan of signals over the entire band, and of course there is much more, but both of those were unusual, so caught my eye. So, SDR's could do this, and if anyone knows of software that performs similarly, please let us know. I'm not a programmer, and I'd be happy to hear of someone who is, that can deliver a worthwhile product, as I've heard that this one doesn't quite cut it.

This was initially developed for assisting live listening with the R8, nearly 10 years ago when SDRs covered only 190kHz or so of bandwidth, but, even in those days, the SDR-14 had a spectrum analysis function for up to 30MHz bandwidth. There's an IRCA reprint from that time describing the details

If live listening isn't your thing, then my system won't be much use to you, unless you operate and record your own copy for later playback. But seeing that it writes to the web (http://www3.telus.net/public/shallpat/test/display.htm), it's a fairly good initial indicator for anyone in a 100 mile radius of here, that maybe you should (or should not?) be using the radio, and it is easier on the eyes than peering at over 1MHz worth of closely spaced lines on a screen, especially on a phone-sized screen, which is what I tend to use to check what is happening on the radio. And once you are warned, and are live listening, its display of a suddenly fading up 1422kHz signal (such as this morning) will catch the eye far faster than one of those closely spaced lines on a normal SDR waterfall. And, yes, SDR has been used for live listening here for over five years, while recording at the same time....no, not a Perseus,

Admittedly, my interest is more in propagation peculiarities than in logging new ones, though I've certainly never turned down the new or unusual ones that have turned up during these searches.

best wishes,

Nick


At 18:54 2018-09-22, Guy Atkins wrote:
My thoughts: what Chuck describes is basically what I do for reviewing SDR
recordings, with whatever software I might be using. Clicking carefully on
the playback bar can also advance the recording in increments of your
choice.

Skipping ahead in one-minute increments makes the top-of-the-hour range
we're generally most interested in go by rather quickly during review. As
Chuck described it only takes your brain a second or two to recognize if
there's any content worth pursuing. If not, then a quick click
fast-forwards you to the next minute for a second or two auditory check.
It's kind of the "30,000 ft. view" of the DX, and if anything seems
interesting you can get more granular in your review & playback...that's
the beauty of SDR because nothing is lost.

What I'm listening for is audio rising up to intelligibility (in the case
of threshold signals that may be worthwhile to follow), or in the case of
signals with decent intelligibility already I'm listening for content clues
that there may be an ID, advertisement, or other helpful content in the
"vicinity" of that moment I'm reviewing. If so, then I dive in for a
careful listen.

This minute-by-minute quick checking method is a great way to get past
music so you can get to an announcer's voice.

The same approach works for bottom-of-the-hour and other in-between times
when an ID *might* be heard. However I save these less productive time
frames for after I've exhausted top-of-the-hour possibilities. As Chuck
said, bad or normal nights are obvious and you don't need to waste your
time. Were conditions shown to be great on your recording? Then you may
have a gold mine waiting for you to dig through...that's the fun of
capturing the entire band with an SDR. DXing "live" with a traditional
receiver or an Ultralight is another kind of fun, too. It's all radio, and
all good  :^)

Guy



On Sat, Sep 22, 2018 at 10:21 AM, Chuck Hutton <charlesh3@xxxxxxx> wrote:

> Nick:
>
>
> If you listen to  a second or two every minute or two, wouldn't you agree
> the needed time is a percenrt or two of what it was?
>
> And many channels won't need attention at all.
>
> And bad or normal nights quickly become obvious and the files don't need
> to be studied.
>
>
> Nothing earth shattering here.
>
>
> Chuck
>
>
>
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Nick Hall-Patch
Victoria, BC
Canada
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