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Aetheradio 29-05-2017 00:45

been thinking of a similar question for part 15 (USA) and LPFM (NZ) broadcast where for me the licence is free 1 watt of FM with antenna restrictions - there are small one man stations in most places

most of these pay a fee around $200 to a copyright consortium per year plus their costs of sourcing the material

so if I use a free stream such as iHeart or Radionomy as the source the royalties are already covered. Or is this different to a home user streaming same content via video sender / WiFi / Bluetooth to speakers around the property?


Quote:

Originally Posted by tpreitzel
While listening to a comment by Ray Robinson of KVOH that he wasn't necessary wedded to shortwave, a flash of inspiration appeared in my mind. ;)

Although I haven't read about this idea elsewhere, I'm fairly sure that this possibility has been discussed previously by other people.

Can the Creative Commons license be extended to include distribution of content solely via shortwave? In other words, create a license for content that is only legally distributed via shortwave frequencies. Maybe, restricting distribution for open content via shortwave will help sustain shortwave's viability.

PS I haven't checked the Creative Commons licenses for quite awhile.


Aetheradio 29-05-2017 00:45

PS I haven't checked the Creative Commons licenses for quite awhile.[/quote]

tpreitzel 29-05-2017 01:12

If such a license doesn't already exist, CAREFUL addition of one to the Creative Commons series should encourage use of the shortwave bands. True believers in the shortwave medium would probably desire such a license. * Done properly, fair use standards in the USA would remain effective so content under such a license could be referenced and discussed elsewhere. With the advent of DRM for broadcasting data, such a license would be timely, I think.

* (I am for previously stated reasons as I will absolutely no longer use the Spynet for anything other than trivial matters). I believe in SETTING the appropriate example by using a flexible and anonymous platform instead of merely following the crowd over a cliff into the Spynet's grid. The smarter elements of the crowd will stop at the edge of the cliff and follow a safer and more secure path. It'll take some time, though.

tpreitzel 02-09-2017 22:39

The DRM Consortium needs to adopt a creative attitude of enticing their members to control their clients' configurations. After all, selling DRM transmitters is only part of promoting DRM.

For example, except for Diveemo, forbid the use of 64 QAM modulation on the HF bands. For Diveemo (if ever standardized), limit targets to less than 2000 miles and MSCs of 64 QAM. For both digital AUDIO and Diveemo on the shortwave bands, short range targets of less than 2000 miles should also use relatively low power with steeper T/O angles and frequencies below 5.1 MHz (60m) or above 17.5 MHz (16m). With the xHE-AAC codec, digital audio on the HF bands doesn't need the bandwidth of Diveemo so an outright BAN of MSCs of 64 QAM should be part of the DRM standard for digital AUDIO transmissions on HF. Unfortunately, DRM SW broadcasters don't seem to have the required discipline to circumvent such a ban.

F1BJB 04-09-2017 07:44

Quote:

Originally Posted by tpreitzel
forbid the use of 64 QAM modulation on the HF bands.

HI
I don't agree that forbidding anything will promote DRM.
On the contrary dynamic changing of modes and frequency according to
target,content and propagation should be promoted.
It will help detecting receivers with too limited features.
Feedback from listeners should allow broadcasters to choose the best mode.
Laurent

tpreitzel 04-09-2017 21:58

Quote:

Originally Posted by F1BJB
HI
I don't agree that forbidding anything will promote DRM.
On the contrary dynamic changing of modes and frequency according to
target,content and propagation should be promoted.
It will help detecting receivers with too limited features.
Feedback from listeners should allow broadcasters to choose the best mode.
Laurent


Laurent,

Although dynamic changing of modes would be better than any static configuration, thousands of logs have clearly demonstrated that 64 QAM modulation has problems on shortwave bands. Modulation of 64 QAM was clearly intended for AAC+ codecs on the MW band, not HF. Consequently, xHE-AAC was added to the DRM standard primarily for use on HF at LOW bit-rates. Hence, we'll have to agree to disagree on that issue.

tpreitzel 06-09-2017 22:43

I was listening to HWN on 7268 kHz (LSB) during the early morning hours last night and the discussion was riveting as I tracked hurricane Irma through the Caribbean just east of Anguilla, home of the Valley SW station. I used the map of the Caribbean in WRTH. ;) Irma was intensifying as it passed near Barbuda. Naturally, the Valley on 6090 kHz was off the air earlier than scheduled. I wonder how the Valley fared this onslaught.

I'm confident that DRM will one day play a major role on the SW bands during disasters such as this unfortunate one. Irma isn't done yet and I'll be listening. Hopefully, one day I'll be reading data via DRM and SW about such events.

tpreitzel 10-09-2017 21:44

Millions of Potentially New Listeners One Disaster Away
 
The title says it all. Younger generations WILL turn to radio as have PAST generations simply because it works under severe conditions. The infrastructure does NOT fail except for brief periods and always recovers by itself and without cost. Younger generations, even this older generation poster ;), expect digital capability, not some boring analog broadcaster. DRM will benefit as a result.

The idea that younger generations will ALWAYS ignore OTA broadcasting is both silly and ignorant. Younger generations are just a disaster away from becoming new listeners.

With the aforementioned said, OTA broadcasting will need to become more on-demand, though, with shorter and greater variety. Future DJs will basically be researchers. Both the Spynet and Spyphone can accommodate immediate interaction when desired. Personally, I prefer more secure mail. ;)

tpreitzel 13-11-2017 00:35

DRM has a problem with its image due to poor digital configurations on shortwave for over a decade. The AAC+ codec was fine for the MW band, but has its limitations on shortwave which unfortunately encouraged shortwave broadcasters to use MSCs of 64 QAM. This problem can only be resolved through sane configurations appropriate for shortwave, i.e. MSCs of 16 QAM, and the xHE-AAC codec. Of the current digital broadcasters, only VoN has an appropriate configuration. Although VoN still has room for improvement within the constraint of 16 QAM, it's main issue even at the currently low bit-rate is poor quality of audio from their remotes. The studio production from VoN is acceptable at such a low bit-rate. However, if VoN ever returns to digital shortwave, they should certainly adopt the xHE-AAC codec instead of AAC+.

Hence, the recovery of DRM's tarnished image will take additional some time and persistence unfortunately. It's high time for shortwave broadcasters to get with the program of robust configurations and the xHE-AAC codec.

zfyoung 13-11-2017 01:23

Quote:

This problem can only be resolved through sane configurations appropriate for shortwave, i.e. MSCs of 16 QAM, and the xHE-AAC codec
This is the only short term stopgap solutions to the HF broadcast problem.
Actually the main complaint I have against DRM is that the codec (AAC+/xHE) remains proprietary product. This not only put a hurdle on wider adoption of modern broadcast standard, it also discourage any attempt to improve or it co-opted to better systems. And indeed there is a far better solution to this kludge: why let the broadcaster to dictate the configuration of transmission signals (64/16QAM, bitrate, AAC/xHE etc.) at TX side, why NOT let the receiver to decide that at RX side depending on the local SNR level? This strategy incorporate the agility of analogue system and efficiency of digital system and DX friendly.

tpreitzel 13-11-2017 21:00

Quote:

Originally Posted by zfyoung
This is the only short term stopgap solutions to the HF broadcast problem.
Actually the main complaint I have against DRM is that the codec (AAC+/xHE) remains proprietary product. This not only put a hurdle on wider adoption of modern broadcast standard, it also discourage any attempt to improve or it co-opted to better systems. And indeed there is a far better solution to this kludge: why let the broadcaster to dictate the configuration of transmission signals (64/16QAM, bitrate, AAC/xHE etc.) at TX side, why NOT let the receiver to decide that at RX side depending on the local SNR level? This strategy incorporate the agility of analogue system and efficiency of digital system and DX friendly.



If you're implying that the DRM standard has asymmetric ability, then I was unaware of that capability. As Laurent suggested, dynamic capability certainly would be better than any static configuration, but asymmetric capability is another matter entirely. Explain to me how your scenario would work with the DRM standard both technically and experientially. Keep it simple and, if appropriate, use the DR-111 as the receiver in any example.

Are you suggesting that if a broadcaster used a 64 QAM configuration, then the DRM standard allows for the asymmetic reconfiguration at the receiver to 16 QAM?

Personally, I support the concept of dynamic configuration at the RX, but I think it's best to place the onus on the broadcaster for the foreseeable future. Yes, the BBC still broadcasts automatic frequency changes when no such frequencies exist and most digital broadcasters can't even broadcast time signals correctly, etc...

P.S. I'm pretty sure that Laurent and yourself are thinking in terms of TX initiated reconfigurations while I'm thinking in terms of RX initiated reconfigurations (adaptions since the RX can't talk to TX) .... For example, I'm outside the target area of a broadcaster, but I want my receiver to decode the digital broadcast if possible. Hence, I need it to switch to a mode where decoding is possible ... IF possible.

zfyoung 14-11-2017 00:49

Quote:

implying that the DRM standard has asymmetric ability
If you confine yourself within the 'rule box' of current DRM standard, then the answer is a resounding NO. That's why I said
Quote:

short term stopgap solutions
. But it does't mean you have to throw out the baby with dirty bath water. what I hinted is that there is Long Term Evolution of this standard (L.T.E. sounds familiar, eh?)that in the ultimate end brings out the best of analogue system and digital system.

PS. NO, laurent and I are talking about two different things, and given my academic background in information theory I know what I'm talking about: "Joint Source Channel Coding". If you not even heard about it, then google it.

tpreitzel 14-11-2017 14:39

Quote:

Originally Posted by zfyoung
If you confine yourself within the 'rule box' of current DRM standard, then the answer is a resounding NO. That's why I said . But it does't mean you have to throw out the baby with dirty bath water. what I hinted is that there is Long Term Evolution of this standard (L.T.E. sounds familiar, eh?)that in the ultimate end brings out the best of analogue system and digital system.

PS. NO, laurent and I are talking about two different things, and given my academic background in information theory I know what I'm talking about: "Joint Source Channel Coding". If you not even heard about it, then google it.


Given some time, I'll look into "Joint Source Channel Coding" ... so thanks for the information. Even without further investigation, I have already concluded that an HD-like system (automatic fallback to more robust digital configurations, e.g. 16 QAM) is preferable to the current DRM standard. The digital receiver needs to make an "intelligent" selection of the proper mode instead of relying on the whims of the broadcaster. However, the overhead would be significantly higher since all the data necessary for such a decision would have to be transmitted concomitantly.

Until the DRM standard is amended, I'll stand by the need for digital SW broadcasters to use MSCs of 16 QAM ... ;)

I'll investigate further though.

Aetheradio 15-11-2017 07:11

It might be possible to change the DRM modulation scheme so the receiver can use high fidelity when the signal is good but remain locked to the more robust signal when conditions are poor - from the same transmitted signal. The scheme adopted for satellite video transmission DVB-S2 allows for this (although I'm not aware of broadcasters using that aspect here)
http://www.etsi.org/deliver/etsi_tr/...76v010101p.pdf
However, anything added now should be backward compatible to existing gen-3
receivers, those who invested in DRM30 or DRM+ reception have been sidelined because of the introduction of xHE-AAC. I think that means only the Gospell and Titus can do DRM now. What about Diveemo?
Also take note what is happening with DAB in Britain: many new stations are starting up in DAB+ only, 32kbs mono. They are not interested in stereo because of the cost. FM analogue and even AMstereo (AMAX) now outperforms it in every aspect of quality. The BBC has to keep its main programmes on the DAB standard due to the millions of expensive car radios and home portables that arn't upgradeable (I have one)
The cellular operators like LTE because more streams over their network= more tariff because unlike broadcast, the listener pays for the transmission costs. LG are selling a DAB+ Android phone here and Australia with the advertised advantage of no data charges and better battery life for the user.

The two things I would like the gen-4 DRM release to include are - Diveemo support and Opus codec support.
The one thing I would like smartphones to have is DAB+,DRM+,AMAX on all bands 0.5 thru 240 MHz

zfyoung 16-11-2017 01:48

1 Attachment(s)
This synthetic picture should give you a rough idea of
Quote:

dynamic configuration at the RX
,depending on the distance between TX and RX.
As what I've said, the best coding scheme should have the sensual analogue form while in spirit, not lost its digital acumen! :cool:

tpreitzel 11-01-2018 17:42

A cursory check of the shortwave bands today impressed me for the first time in my life, i.e. fairly clean bands. Even a noisy neighbor who routinely violates FCC regulations was absent ... ;) So, step number 1 has been largely accomplished with the exception of some state broadcasters still polluting the bands with propaganda. Hopefully, those remaining state broadcasters will soon leave shortwave for the Spynet where they can snoop on their listeners.

Now, digital shortwave is ready to take flight with commercial entities and their good, if not great, content that enriches and truly informs their listeners. Despite some naysayers, the potential of DRM on frequencies capable of international transmission is just too tremendous to ignore forever. We're close to a renaissance. I wish I could say exactly when that renaissance will flower, but it has budded in my opinion.

Ah, the shortwave bands are so clean this morning ... just waiting for good content delivered digitally.

I started this thread in an attempt to improve the digital experience on shortwave. I still believe every word written by me. The phrase, "ignorance is bliss", has WRONGLY acquired a negative connotation over the years. All humans are ignorant and increasing specialization has only worsened the disparity. Life is balance and unwise choices frequently have disastrous effects. Ignorance is actually an important defense mechanism which helps humans cope with overload so CHOOSE wisely and ENJOY life. Study some, but observe much. Don't trust anyone, even people with governmental degrees. Experiment yourself as time allows. Use that radio to forecast propagation as much as possible. Hopefully soon, we'll have some good digital content to enrich our lives as well.

tpreitzel 29-01-2018 16:06

As a continuation of the theme of my previous post about balancing one's time, a combination package consisting of Gospell's GR-216 receiver and W6LVP's magnetic loop for sale for $500 would be a great idea! I can't think of a better deal for a SWL in the immediate future.

tpreitzel 08-02-2018 00:04

AGAIN, the MAIN problem with the slow adoption of DRM has been broadcasters' poor choice of 64 QAM modulation on the shortwave bands. Even AIR experimented with 64 QAM with ultra low bit-rates of ~ 8 kbps and the results like RNZI's use of 64 QAM were sub-optimal for shortwave when modest interference and propagation degraded the signal. * 64 QAM modulation has NEVER and will NEVER work well, i.e. reliably, on shortwave as thousands of logs demonstrate. Bit-rate certainly plays a role in a listener's ability to reliably decode a digital broadcast, but that role is clearly secondary to the modulation scheme. Unfortunately, this irresponsible use of 64 QAM modulation by digital broadcasters has given DRM a tarnished image on shortwave which will ONLY be overcome with the widespread adoption of 16 QAM modulation.

* RNZI's transmitter is located in a nearly perfect spot as well and it still didn't function reliably enough under the FREQUENTLY sub-optimal conditions found on shortwave.

Aetheradio 10-02-2018 02:00

The main problem with DRM is nobody can buy or build a receiver that complies fully with the current standard.
It must have both DRM30 and DRM+
It must have all codecs and rates including xHEAAC

The modulation doesnt matter much between 64QUAM and 16QUAM on shortwave. I did enough practical on air tests to show there was maybe a half dB in it. Once your reception gets in the noise below minimum thats it. When things are this bad, only AM works.
The BBC tests on MW went to lower constellation at night due to adjacent channel interference. This is no longer a problem on SW because most everybody has left.

Ralph

AF4MP 10-02-2018 15:42

Quote:

Originally Posted by Aetheradio
The modulation doesnt matter much between 64QUAM and 16QUAM on shortwave. I did enough practical on air tests to show there was maybe a half dB in it.


Thank you!

tpreitzel 10-02-2018 19:24

Alokesh,

Thanks for posting this news. I especially like the promotion of the non-audio aspects of DRM as this aspect is precisely the component that has the most potential for informing the "listener". I, too, would like to see DIVEEMO both standardized and promoted.

Now, if AIR would only restart DRM broadcasting on shortwave with 16 QAM modulation and the xHE-AAC codec from their transmitter in Bangalore!

http://alokeshgupta.blogspot.com/201...ed-at-bes.html

tpreitzel 10-02-2018 19:25

Quote:

Originally Posted by Aetheradio
The main problem with DRM is nobody can buy or build a receiver that complies fully with the current standard.
It must have both DRM30 and DRM+
It must have all codecs and rates including xHEAAC

The modulation doesnt matter much between 64QUAM and 16QUAM on shortwave. I did enough practical on air tests to show there was maybe a half dB in it. Once your reception gets in the noise below minimum thats it. When things are this bad, only AM works.
The BBC tests on MW went to lower constellation at night due to adjacent channel interference. This is no longer a problem on SW because most everybody has left.

Ralph


Ralph,

Logs on this forum and the experience of other members including myself clearly demonstrate otherwise. The threshold for decoding 16 QAM is MUCH lower at the receiver than 64 QAM even on the MW band. I should know as I have tested it with my DRMAX-1 transmitter. Furthermore, I don't have access to your tests so I can't and won't comment on them specifically. Regardless, ANY lowering of the threshold for decoding a DRM signal on shortwave is an improvement so, again, the use of 16 QAM on shortwave is absolutely necessary to MAXIMIZE decoding for the listener and supported by the thousands of logs on this forum. Therefore, we'll have to agree to disagree.

The inclusion of other codecs isn't really necessary in the DRM standard as xHE-AAC finally realized DRM's potential on shortwave when used in conjunction with 16 QAM ONLY modulation. Opus might be nice, but it certainly isn't necessary now with the advent of xHE-AAC.

As far as including DRM+ capability in receivers, it's not really necessary either, but would probably improve the market for a DRM receiver.

In conclusion, I'll agree partly with your comments that shortwave listening is currently declining because of both ignorance and convenience. Both of these latter factors can and will likely be overcome when more desperate times arise for an individual or even country ... Life isn't always rosy or cozy.

tpreitzel 23-04-2018 03:30

"Old" Analog Concept of Targeting Nations
 
With the multiple service capability of DRM, the old analog idea of narrowly targeting nations should be dying, but won't until those analog broadcasters die as well unfortunately. It's an awful thought, but apparently true. Engineers are so conditioned by ideology and practice, it'll be difficult to change the situation until new engineers arrive on the SW scene along with further refinements in low bit-rate compression. This latter process is already occurring, but will require more time. I'm NOT saying there will NEVER be a need to target a nation, but that the general practice will decline as multiple service capability is properly employed.

Even with 16 QAM modulation, the current DRM xHE-AAC codec can readily accommodate multiple audio streams and languages with decent quality. Even now, the perceived need for narrowly targeting nations via shortwave is rapidly disappearing and SW broadcast engineers need to rethink their old habits.

tpreitzel 21-06-2018 16:42

If it's possible, the DRM standard will soon have to incorporate 4 QAM modulation into the standard which will be a boon for digital shortwave. Then, digital shortwave broadcasters should be restricted to either 4 or 16 QAM modulation. The continuing research of incorporating AI techniques into codecs will allow audio from ultra low bit-rates below 3 kbps. Essentially, we're already there. Dolby has purchased Coding Technologies and released AC4. Opus will be following the others into the lower end a la Codec2 and its variants. All of this research will be a boon for digital shortwave and its listeners.

tpreitzel 28-06-2018 01:28

Video ports, e.g. HDMI, should be a standard component on digital radios as well as COMPACT IR remote controls on desktop units. When I'm working on various tasks, I don't want to have to stop and twiddle knobs or walk to a radio with a small screen to read data. An HDMI port will allow me to connect a micro projector. Although radio on VHF, HF, and MW bands will probably always remain a primarily audible experience, I can definitely foresee visual data increasing its share of that experience. Hence, designers and manufacturers need to prepare now. Radio data is primarily an attachment to an old analog paradigm. Purely digital technologies like HD, DRM, and DAB haven't been properly deployed since their inception. Again, the old analog paradigm has been replaced so stop thinking within the boundaries of its mental cage.

User-friendly digital radio is flexible and anonymous which are the main reasons for my continued involvement with DRM.

tpreitzel 31-07-2018 14:00

Digital IS the way forward on broadcasted bands. I was listening to Ted Randall of WTWW who was promoting his advertisers on shortwave and wondered about his effectiveness. Since the advent of the Spynet, listeners want comparative information before buying products which can only be done digitally. It's possible to promote SERVICES adequately on analog platforms, but I'm not so sure about PRODUCTS. Today, people expect reviews, both pro and con, on products before purchasing. Asking those potential buyers to access the Spynet is both cumbersome and unnecessary. Why not just use a digital platform such as DRM and broadcast that extended information so a buyer can decide without having to access the Spynet?

Digital broadcasters need to update their ancient analog thinking again, in this case, the promotion of their advertisers' products.

tpreitzel 04-09-2018 21:50

Congratulations to this Indian radio club for their educational program featuring DRM. Hopefully, Indians will conduct more such informal sessions. I'd like to see other nations conduct similar sessions, but the limited availability of broadcasts is problematic.

https://alokeshgupta.blogspot.com/20...t-chennai.html

tpreitzel 12-10-2018 21:45

Content
 
This thread is generally about simplifying digital reception on the broadcasted bands, primarily shortwave, for the masses. I've already discussed rational and robust configurations for digital shortwave. If broadcasters want to be heard with reasonable quality on shortwave, they should heed my recommendations. Now, let's look at content briefly.

The masses want the truth, but aren't generally willing to expend the effort to find it. Hence, unscrupulous broadcasters have lead to the rise of the mass media, or propaganda for the lazy masses.

With the aforementioned said, scrupulous broadcasters will attempt to provide those lazy masses with the truth. However, the truth will likely NOT be found in regurgitating one's biases over the air. Truth is found by diligently searching for all possible facts, incidental or direct, regarding a topic. For example, Dr. Michael S. Heiser, a biblical scholar with a different view than many in his field, has the ability and sufficient training to adequately interpret ancient texts. Michael's views on the paranormal can be found in his work, "The Facade", as well as more recent publications. I use Dr. Heiser as an illustration of someone who would serve as a counterpoint to some of the traditional interpretations found in ancient texts which should be broadcasted over the air. In EVERY field of human endeavor, a scrupulous broadcaster should monitor his own biases before selecting content to air.

Remember, the masses WANT the truth, but aren't willing to expend much effort to do so which is a weakness that unscrupulous broadcasters exploit.

tpreitzel 09-04-2019 04:46

Another Reason Why SW Broadcasters Need Digital
 
Limited bandwidth which SBR can effectively overcome. Most analog SW broadcasters don't equalize their broadcasts for the limited bandwidth of SW and the audio just sounds terrible, i.e. muffled and boomy, as a result. Non-equalized audio especially music on analog SW sounds awful unless broadcasted with at least 30 kHz of bandwidth. Personally, I can't listen to non-equalized WTWW on 5085 kHz for more than 5 minutes without getting a headache.

I've attached a sample recording of an analog SW transmission, Radio Marti, on 7355 kHz, after applying a steady roll-off of lower frequencies from ~ 800 Hz to 50 Hz (cutoff). The mid-range frequencies are largely flat and unaltered while the high frequencies are less steeply rolled-off beyond 6 kHz in case Cuba decides to broadcast 30 kHz, distorted analog... LoL I don't really alter this configuration much at all even though audio frequencies beyond 6 kHz are largely non-existent on SW. A multi-band parametric equalizer, qpaeq, was applied to the 7335 kHz transmission received via an SDRPlay RSP-1A and CubicSDR along with Speex NR from DReaM at -9 dB.

A properly equalized broadcast will sound progressively better with better audio equipment while retaining its balance.

http://s000.tinyupload.com/index.php...48056311313893

tpreitzel 16-04-2019 02:16

A continuation of post #69 to illustrate the magnitude of processing required to produce adequate analog audio on shortwave:

https://ibb.co/yNj0LRH

This screenshot is busy and requires some explanation. First, a SOAPY RTL-SDR driver was used instead of a SOAPY RSP-1A driver since I was using an RTL-SDR V3 SDR on the Q-channel, i.e. no upconverter. The audio was managed by PulseAudio's Loopback device and routed to the I/Q Neg Split channel on DReaM's input. DReaM's output was via the FFT of the multi-band equalizer, qpaeq, on PulseAudio's default output device.

The reception and sound quality are quite good considering the use of a $20 dongle and 30' of wire antenna (MMDs-31). All of the rest of the processing was handled via software. Granted, the listener to these larger SW stations shouldn't NEED to equalize their unbalanced broadcasts on limited bandwidths as it's the transmitting station's responsibility. Furthermore, some limitations of analog just can't be overcome without digital.

tpreitzel 17-04-2019 05:16

Maybe I'm dreaming, but WTWW on 5085 kHz actually sounded much better tonight, April 16, 2019. Has Ted actually equalized WTWW tonight? If so, the sound is sooooo much better balanced than normal, Ted. If you want at least 10 kHz of audio bandwidth, Ted, please consider robust, i.e. 16 QAM, DRM with SBR. It CAN be done, Ted, and the quality will be vastly superior to anything you can broadcast in analog in 12 kHz of RF bandwidth. I actually enjoyed WTWW tonight from my higher quality audio system even with WTWW's limited 6 kHz of audio spectrum. Talk radio can be adequately done in analog on SW, but music is definitely hard to do and must be equalized to retain balance in RF bandwidths under 30 kHz.

tpreitzel 29-04-2019 00:28

As I hinted when I first joined the DRM Software Forum years ago, more is happening with the atmosphere than natural phenomena. I'll even add that anthropomorphic geoengineering isn't helping the continuance of shortwave and its digital counterpart one iota either. Yes, geoengineering consists of various technologies, but all of them need much closer scrutiny. At the very least, more attention needs to be focused on geoengineering and its potential effects on radio propagation.


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