KSWD Out-of-band Emissions

[TheDaChicken]

This is just ridiculous. For the past 4-5ish months, KSWD has been outputting tons of noise. Basically ruining their own HD bands.

From my SDR (shown like this on all my SDRs including HF+ Discovery):


I don't think there is anything I can really do??

 

[luperm]

This is just ridiculous. For the past 4-5ish months, KSWD has been outputting tons of noise. Basically ruining their own HD bands.

From my SDR (shown like this on all my SDRs including HF+ Discovery):
View attachment 10754

I don't think there is anything I can really do??

You could maybe send a note to the station? Just a thought. I'm sure their engineer would appreciate your interest.

 

[radiofan2023]

Contact | Emma 94.1

Contact | Emma 94.1

www.audacy.com

From that page:


Audacy Washington, LLC | Emma 94.1 Seattle
Studio Phone: 206-467-0941
Office Phone: 206-577-8600

 

[fordranger797]

100% call Audacy to let them know. A lot of time, engineers don’t realize that something like this might be off (as they already have a million other things going on and don’t notice unless something is overtly amiss).

 

[cc-mar]

I sent this on to someone I know who works there.

 

[SomeRadioGuy]

This is just ridiculous. For the past 4-5ish months, KSWD has been outputting tons of noise. Basically ruining their own HD bands.

From my SDR (shown like this on all my SDRs including HF+ Discovery):
View attachment 10754

I don't think there is anything I can really do??

I've seen many a time when stuff like this shows up but it turns out to be overload/intermod/spurs, whatever because of overload somewhere in line between the SDR and antenna

 

[TexasTom]

I've seen many a time when stuff like this shows up but it turns out to be overload/intermod/spurs, whatever because of overload somewhere in line between the SDR and antenna

I'm a retired electrical engineer -- but worked with radar systems, not radio stations. Nonetheless, this does look familiar.

I've seen something familiar from putting running too much power from a module that generated the RF waveform into the module that upconverted and amplified the signal before sending it on to the power amp. On the other hand, I've also seen similar waveforms from a misadjusted spectrum analyzer. The bottom line is that this could potentially be caused by anything in the RF chain from the output of the modulator to the spectrum analyzer.

 

[Anton P]

This is from RTAC not enabled in the exciter. Engineers have been notified.

 

[TheDaChicken]

I've seen many a time when stuff like this shows up but it turns out to be overload/intermod/spurs, whatever because of overload somewhere in line between the SDR and antenna

Yep, I made sure to double check with the many SDRs I have. HF+ Discovery is known for not much overload. All with the same problem.


Look at that, it's completely gone.
Thanks y'all I really appreciate it! I didn't think that would do anything.

100% call Audacy to let them know.

Does that really work? The amount of issues I see with radio stations, I wish there was an easy way to contact. I don't much have reach. Its such an issue that I can bring up a different issue with another Audacy radio station here.

 

[Anton P]

I can bring up a different issue with another Audacy radio station here.

Sure, we can forward it to relevant people there.

 

[fordranger797]

Yep, I made sure to double check with the many SDRs I have. HF+ Discovery is known for not much overload. All with the same problem.
View attachment 10781

Look at that, it's completely gone.
Thanks y'all I really appreciate it! I didn't think that would do anything.



Does that really work? The amount of issues I see with radio stations, I wish there was an easy way to contact. I don't much have reach. Its such an issue that I can bring up a different issue with another Audacy radio station here.

Engineers are modern day broadcasting miracle workers, but they don’t always know that an issue exists unless someone brings it to their attention. It never hurts to call and leave a message (as a “hey, by the way…”). The issue you raised is something that would probably be hard to know about unless someone discovered it.

 

[radiofan2023]

Engineers are modern day broadcasting miracle workers, but they don’t always know that an issue exists unless someone brings it to their attention. It never hurts to call and leave a message (as a “hey, by the way…”). The issue you raised is something that would probably be hard to know about unless someone discovered it.

And tell them you have a visual of it that they can look at

 

[bobdavcav]

I am assuming a problem like this would not be noticed by the average listener? I was in the market this weekend and recorded about 75 minutes of 94.1 on Friday afternoon and it sounded fine.

 

[fordranger797]

I am assuming a problem like this would not be noticed by the average listener? I was in the market this weekend and recorded about 75 minutes of 94.1 on Friday afternoon and it sounded fine.

No, you’d likely need some sort of visual graph to what’s going on here. Alternatively, you could probably hear it with a radio if you could tune very slowly (94.15). But for the vast majority of listeners, there would be no change.

 

[Anton P]

I am assuming a problem like this would not be noticed by the average listener?

You'd notice weak 93.7 and 94.5 stations sounding noisier than usual due to overlapping IMD noise from 94.1

 

[TheDaChicken]

Sure, we can forward it to relevant people there.

This one may be hard to explain to those who don't know much about radio sound processing. This does actually effect audio.

KHTP audio is somewhat messed up. Somewhere in the STL or path to transmitter is causing audio tilt. This means the MPX waveform isn't stable. A specific frequency range like bass can create a higher modulation level. An Audacity Engineer must have reduced modulation to compensate to stay within legal limits of 75khz without fixing the issue by either changing settings in their radio processor or fixing cables? This results in quieter audio and some dullness. I like Hip hop. This ruined some of the experience listening to KHTP.

Here's a video of the MPX waveform:

When bass kicks in, instant modulation increase (% of modulation is displayed) & tilt in MPXTool. No clue if this is already a known issue.

Here's KQMV (CLIPPED SUPER HARD) as a reference of what "stable" looks like in a waveform.

Since this is in the Seattle category, I don't know if its OK to mention stations in different markets. Some may only be checking certain categories. Since I think its interesting (others may find it interesting), I made another fourm post in correct category to talk about another Audacy radio issue:

https://radiodiscussions.com/threads/wpht-is-broadcasting-over-their-hd-bands.778599/

 

[bobdavcav]

KQMV is still super clipped on the low end? I honestly haven't noticed that in years, but I really noticed it in 2012-13.

 

[TheDaChicken]

KQMV is still super clipped on the low end? I honestly haven't noticed that in years, but I really noticed it in 2012-13.

Yep. I don't know how bad it was in 2012-13. The waveform is still clipped hard with zero peaks. I sometimes get used to it that I never hear it.

 

[bobdavcav]

It's probably the same as it was back then, I don't think that station's processing has changed at all in the last several years. I can't say the same thing about 106.1 though. That station sounds like it's broadcasting from one of those rooms you can go into and be completely shielded from external noise. There's a specific term for those but I can't remember what it is.

 

[TheDaChicken]

That station sounds like it's broadcasting from one of those rooms you can go into and be completely shielded from external noise.

Yep I 100% agree. There was a period of time I liked the processing on 106.1. It was when KUBE in 2021 existed. I felt like it was a great mix of distortion.