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Messages - KaySeeks

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421
I saw the TX turn on on my SDR waterfall and immediately retuned to the signal.
0828 - Announcement in Dutch between songs. Too weak and fading too much to hear the announcement clearly.

422
Man of Action at 0805 UTC.
Excellent reception in Austria at 0810 UTC then rapid fade down over the course of 2 minutes to SINPO 15111.
Reception has improved. Listenable at 0846 UTC.
Dutch C&W song at 0847 UTC.

423
This doesn't sound like the usual Sunday-morning religious broadcast.  :D Upbeat contemporary and "classic pop" music. No announcements so far. Probably from the Netherlands.
Frequency is 6289.99, in case anybody cares.
0819 - Sounded like a brief announcement between songs, then into a Big Audio Dynamite Song. Fading down now.
0823 - Slow deep signal fades.
0833 - TX off the air mid-song.

(edit time in the subject line and tentative ID - Ray)

424
Presume that this is Laser Hot Hits. Christmas-themed dance music at 0745 UTC. SINPO 35333 on an SDR in Austria.

425
1801 - Thompson Twins, Love on Your Side. SINPO 54455 on an SDR in Southern Germany, expect for a local (to the RX) buzzy signal.
1803 - "Email to us at All 80s JukeBox dot com to let us know your favorite request." This is a relay of an Internet radio station and is // to their Internet stream: https://players.rcast.net/popup1/61801
1804 - (I Want) Candy.
1820 - Seems to be best audible in the vicinity of The Alps and very poor everywhere else.

426
Extremely weak on SDRs in Belgium, southern Germany and Denmark. SINPO 15311.

427
Checked back at 1620 UTC and hear no signal.

428
The usual programming. ID and frequency announcement in English at 0855 UTC then into a German song.
SINPO 35333 on an SDR in England.

429
General Radio Discussion / Re: HD FM Audio Drives Me Nuts
« on: December 11, 2019, 0108 UTC »
There is a long standing theory that American DAB (HD) has a self-noising property.  Some more detail can be found here http://ham-radio.com/k6sti/hdrsn.htm

Quote
An HD Radio station's digital sidebands may interfere with reception of its own analog signal in two ways. First, FM detection of the sidebands may generate intermodulation products that overlap the analog signal. Interference also may occur when the stereo decoder demodulates the digital sidebands along with the stereo subchannel signal. Because the digital subcarriers are numerous and their data randomized, analog detection yields noise. This form of HD Radio self-noise is the subject of this article.

OK, but what I am hearing happens when listening to the digital signal, not the analog signal.

Also within the last few years, the Arbitron PPM system has been toyed with by several manufacturers in an attempt to boost the host stations' ratings.  They do this by making the PPM signal louder, and in many cases unmasking the tones.  It seems to be most noticeable on dry voice, and makes the announcer sound as if they are in a broom closet, or talking through a paper towel tube. The device responsible for this is made by Telos, called the voltair.  https://www.telosalliance.com/25-Seven/Voltair

OK, yes, what I hear is more noticeable with voice because here is less spectral content to clutter the air. Not sure about the closet, but maybe there is a little bit of paper towel tube there, yes, but only at high frequency. At lower frequencies there is no problem.

I'm still thinking it's more about artifacts of the restoration from digital.

430
General Radio Discussion / HD FM Audio Drives Me Nuts
« on: December 10, 2019, 2043 UTC »
Perhaps some of the folks with broadcast industry experience can comment on this.

I note on good receivers that FM HD audio has some annoying high-frequency (~10-20 KHz) residues or artifacts. It almost sounds like a reverb at those frequencies and is more noticeable with speech than with music.

If I turn off HD mode on the receiver, I get a lot less of this (but it's still there to some degree) but regardless I still end up turning the treble all the way down because these artifacts drive me nuts. I have heard this on multiple receivers. I do not hear the same artifacts on non-HD stations. I can say that it may depend upon the transmitter being listened to but not 100 % sure on that.

I don't know the exact source of this. It might be due to phase shifts in that frequency range but I am not sure. (I wonder what a group delay plot of the audio spectrum on HD modulated audio looks like.) HD audio is supposed to be flat and not use the high-frequency pre-emphasis used in analog FM so, in theory the group delay before the encoder would be kinda flat (...but after restoration to analog at the receiver it might look very different). I'm guessing that it is some artifact of the audio sampling and the bit-rate stream, perhaps aliasing issues. I did some searching but was unable to come up with a discussion of something similar. I did find this document on HD audio processing and alludes to artifacts but doesn't get into specifics:

https://www.telosalliance.com/images/Omnia%20Products/White%20Papers/Audio_Processing&HD-Radio.pdf

Quote
Employing a clipper as a peak limiter in a HD Radio system will work, but there are sonic penalties to be paid. Any clipping process yields harmonics of the fundamental source signal, and even with distortion masking some second order harmonic  content will remain. This adds to the audio spectrum and aggravates the encoder, which in turn spawns additional sonic   artifacts. This is particularly noticeable in the high-frequency range where most codec  artifacts exist and is very noticeable with certain program material; therefore, another form of peak limiter is needed.

(Bottom of page 2, right column)

Does anyone recognize these artifacts and know the origin?

431
General Radio Discussion / Re: YHWH
« on: December 10, 2019, 1931 UTC »
Has been on the last two days - 11650khz - as early as 1850z as late as 2010z - 12/7 and 12/8.
FPE

Yes, I saw this in the Glenn Hauser's World of Radio email list on Sunday too.

432
SINPO 55434 on SDR in Austria at 1925 UTC. Fading is fairly rapid but the signal is so strong that it doesn't matter much. This would be a good situation for a synchronous detector.

433
Yeah, the fact that it is being jammed is a big indication that it's Korean and not Japanese.

434
Guessing this is Radio Continental but not sure, Signal is very weak.
...and as soon as I post the TX is of the air.  :(

435
1845 - AC/DC, Back In Black
1849 - Elvis Presley song. SINPO 34333 on SDRs in Austria and Germany.
1858 - Creedence Clearwater Revival song.
1902 - Latin music. I have it on 3904.92 KHz.
1906 - I keep hearing professional-sounding announcements between songs. In this case it sounded like "POWER!" but I am very unsure.
1911 - In English with Dutch accent, "On shortwave...(static crash)...East Coast Holland" and TX immediately off the air.

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