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Loggings => North American Shortwave Pirate => Topic started by: Kilokat7 on September 09, 2018, 0309 UTC

Title: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: Kilokat7 on September 09, 2018, 0309 UTC
S9 with jazzy tune and very wide audio, sounding great here!

0311: "Thank you for tuning into Mix"
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: MDK2 on September 09, 2018, 0313 UTC
0313 Very nice signal here in Denver tonight, with some smooth jazz. Thanks for the show!
0315 YL Mix Radio ID into more music.
....
0410 "Everybody Wants Some" Van Halen  - I've kept this on in the background as I get ready for bed, heard Steely Dan, Gerry Rafferty, and other soft rockers and smooth jazz over the past hour, so this transition is a bit of a contrast. Still listening!
0444 still on, but I have lightning so I'm unplugging. Good night!
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: bandarr3000 on September 09, 2018, 0316 UTC
 0316 - ID into smooth jazz.  About a 222 SIO here with some fades.  Bands are quiet, which helps.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: Treehouse SWL on September 09, 2018, 0335 UTC
Been listening here since 0313 UTC. A very good signal here with just mild fading and almost no SSB distortion.

Still listening at 0420 UTC, though the signal's not coming through as strongly as it was an hour ago.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: ChrisSmolinski on September 09, 2018, 1720 UTC
SDR recording catch
0229 Came on with a very wide signal, about 13 kHz. Madonna "Open Your Heart". SIO 444
0233 Instrumental music, smooth jazz sound.
0235 Off.
0253 Back on, weaker now, SIO 333.
0458 Off. Thanks for the show, Mix Radio!
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: Kilokat7 on September 09, 2018, 2058 UTC
Posted my reception to YT showing signal and wideband audio.  A few minutes into this and you'll forget your listening to sideband...and on shortwave nonetheless.  If anyone argues that sideband sucks for music then please direct them to this before YT mutes it for a copyright violation:

https://youtu.be/M4k6jDbVxHA

Mix Radio: nice job!
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: TheRelayStation on September 09, 2018, 2212 UTC
Posted my reception to YT showing signal and wideband audio.  A few minutes into this and you'll forget your listening to sideband...and on shortwave nonetheless.  If anyone argues that sideband sucks for music then please direct them to this before YT mutes it for a copyright violation:

https://youtu.be/M4k6jDbVxHA

Mix Radio: nice job!
i have no argument about broadcasting in SSB, it certainly is much more efficient than AM and as a result, "gets out" much further but its pretty much useless for music if you cant broadcast with an audio range of at least 60Hz to 4Khz.
the issue is with some SDR software that demodulates SSB, by default, limits bandwidth and audio quality because the creators of this software did not anticipate or expect content that would require higher demod bandwidth with full range audio such as music, leaving much to be desired when the end user wishes to listen to the broadcast on a high fidelity sound system.
the only piece of SDR software i have found that allows you to customize the demod bandwidth and audio to limits unheard of concerning other SDR software is Sodira.
i think it would be helpful to those of us who are seeking to demodulate a transmission in high fidelity for playback on a sound system, to know exactly which SDR software supports unlimited demod bandwidth and audio adjustments, i had to install many different SDR software to find what i desired.
now while Sodira doesnt have the same graphical waterfall display as other SDR software, it does have options that currently do not exist in any SDR software (that i know of) - i just wish the creator would make some improvements to Sodira and post a newer version as there are a few bugs in the current version.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: MDK2 on September 09, 2018, 2253 UTC
i have no argument about broadcasting in SSB, it certainly is much more efficient than AM and as a result, "gets out" much further but its pretty much useless for music if you cant broadcast with an audio range of at least 60Hz to 4Khz.
the issue is with some SDR software that demodulates SSB, by default, limits bandwidth and audio quality because the creators of this software did not anticipate or expect content that would require higher demod bandwidth with full range audio such as music, leaving much to be desired when the end user wishes to listen to the broadcast on a high fidelity sound system.
the only piece of SDR software i have found that allows you to customize the demod bandwidth and audio to limits unheard of concerning other SDR software is Sodira.
i think it would be helpful to those of us who are seeking to demodulate a transmission in high fidelity for playback on a sound system, to know exactly which SDR software supports unlimited demod bandwidth and audio adjustments, i had to install many different SDR software to find what i desired.
now while Sodira doesnt have the same graphical waterfall display as other SDR software, it does have options that currently do not exist in any SDR software (that i know of) - i just wish the creator would make some improvements to Sodira and post a newer version as there are a few bugs in the current version.

If I understand the question, it's that you'd like to know if SDR software allows you to adjust SSB bandwidth beyond 3 kHz? If so, SDRuno is one that allows that. I can just click on the passband and drag it as far as I can. I found with Mix Radio's signal that there was too much noticeable high pitched hiss when I took it up to 6 kHz and that having it at about 4 kHz was ideal. That could be in part due to relative signal strength at my QTH - it was never what I'd give a 555 SIO rating, but it's been at least 444, meaning that if I were getting the full signal, perhaps there would be little hiss with a bandwidth setting greater than 4 kHz.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: ChrisSmolinski on September 09, 2018, 2312 UTC
I think every SDR app I have allows you to adjust the bandwidth, SdrDx lets you go to 20 kHz for example.  The problem, as MDK2 notes, is one of signal quality / hiss. There's usually very little transmitted spectral content above a few kHz, most of what you hear about 3 or 4 kHz is noise, unless the signal is extremely strong. I have occasionally opened up the bandwidth on a wide pirate transmission but it is rare. Of course this is an issue for AM as well as SSB. My personal opinion is it's not terribly useful for most SW broadcasts (SWBC or pirate) to use very wide bandwidths. Now ask me what I think about DRM, but I won't be so polite with my answer  ;D
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: TheRelayStation on September 10, 2018, 0104 UTC
I think every SDR app I have allows you to adjust the bandwidth, SdrDx lets you go to 20 kHz for example.  The problem, as MDK2 notes, is one of signal quality / hiss. There's usually very little transmitted spectral content above a few kHz, most of what you hear about 3 or 4 kHz is noise, unless the signal is extremely strong. I have occasionally opened up the bandwidth on a wide pirate transmission but it is rare. Of course this is an issue for AM as well as SSB. My personal opinion is it's not terribly useful for most SW broadcasts (SWBC or pirate) to use very wide bandwidths. Now ask me what I think about DRM, but I won't be so polite with my answer  ;D
sorry, im just venting at my frustration trying to locate SDR software that can reliably demodulate certain QAM streams like 802.11/QAM256/ATSC/8-VSB-TV/Cellular/etc.
i have to take "crude" home made measures to get what i desire at this point.
all i need is the (properly) demodulated signal to feed the software i have.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: JimIO on September 10, 2018, 0356 UTC
I listened to that yt clip. I've never heard selective fading affect AM like that. The bass was fluttering. I don't know how to explain it but it probably has something to do with low audio frequencies being on the edge of the signal in SSB and near the center in AM.

Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: Radio Station on September 10, 2018, 1450 UTC
The YouTube video says it all. It is left up to how well it can be received. The transmitting station should not limit the bandwidth because some cannot get a good enough signal and can't receive the full bandwidth. As with HF propagation other stations in other areas will receive a better signal and bandwidth. As far as the bass fluttering that is because the receiving SDR is not zero beating meaning it is not exactly on frequency with the transmitting station.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: JimIO on September 10, 2018, 1539 UTC
"As far as the bass fluttering that is because the receiving SDR is not zero beating meaning it is not exactly on frequency with the transmitting station."

I disagree. The bass fluttering was the amplitude varying not the frequency.
There is no zero beating going on because there is no carrier. If there was frequency shifting it would be constant and not affect the amplitude.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: Radio Station on September 10, 2018, 1558 UTC
That is because it is changing phase at the same time which will change the amplitude by the null effect. This will be most noticed at low frequencies because of being closer to the beat offset of zero frequency. If the receiving SDR was moved up into 20Hz USB  it would cut off anything lower and you will not notice the effect at all. If you look at the video closely you will see the SDR is below zero into LSB about 500Hz. By the way there is a carrier that raises up and down with the modulation on SSB. It is just suppressed. That's how sideband works.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: TheRelayStation on September 10, 2018, 1601 UTC
"As far as the bass fluttering that is because the receiving SDR is not zero beating meaning it is not exactly on frequency with the transmitting station."

I disagree. The bass fluttering was the amplitude varying not the frequency.
There is no zero beating going on because there is no carrier. If there was frequency shifting it would be constant and not affect the amplitude.
actually, if you look at the video, you can see the passband is below the center of the frequency going into the LSB of 6873Khz at about -200Hz.
this is because Mix has some low frequency audio (0Hz to 100hz) on the LSB of the carrier, so KiloKat7 moved the passband to that area not realizing that there will now be a slight frequency difference between both the transmitting station and the receiving station, about 5Hz, creating the "flutter" effect.
if KiloKat7 moved the passband to 0Hz on the USB of 6873Khz (0Hz to 13Khz), the "flutter" effect of the slight frequency difference of about 5hz would not be heard.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: JimIO on September 10, 2018, 1700 UTC
I listened and 'watched' again. So it's not really SSB but more like VSB because there is some lower sideband and carrier. My bad. Is that as wide as he could make it display?

I wonder what it would have sounded like in AM mode.

Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: TheRelayStation on September 10, 2018, 1851 UTC
I listened and 'watched' again. So it's not really SSB but more like VSB because there is some lower sideband and carrier. My bad. Is that as wide as he could make it display?

I wonder what it would have sounded like in AM mode.
like SSB would sound in AM, because there was no sign of any carrier.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: JimIO on September 10, 2018, 1924 UTC
Where is the peak at 6873.000 Khz coming from? Does anyone know the artist/title or a link to the track so I can listen to the original? Last post on this by me.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: Radio Station on September 10, 2018, 2117 UTC
Where is the peak at 6873.000 Khz coming from? Does anyone know the artist/title or a link to the track so I can listen to the original? Last post on this by me.


The peak is the SSB carrier with strong low frequencys on each side noted in color.

The songs are. Special EFX - Deep As The Night
                      Eric Valentine - Back To The Groove
                      3RD Force - Breakout

Look them up on YouTube.
Title: Re: Mix Radio 6873 USB 0308 UTC 09 Sep 2018
Post by: JimIO on September 10, 2018, 2209 UTC
"Look them up on YouTube."

Of course.
Thanks!