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A New Use for Shortwave Frequencies

Kelly A said:
But at such low bitrates, that actually adds several milliseconds over just about anything else.
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That's a good point, but I'm not sure that they are transmitting data in the conventional sense. I think it may be much more simple, as in "carrier on" means "variable a", and "carrier off" means "variable b".

In a similar system I've seen on an SDR, there were 10 carriers within 5 kHz. In the proposed system, they want to use 50 kHz, so with the same system, that would be 50 carriers, where different on/off combinations could mean different things.

That's the impression I've gotten from following this over the past few years.
 
fybush said:
The piece I'll admit I don't get, and perhaps someone smarter than me does, is that the data being transmitted over the shortwave signal still has to get TO the shortwave transmitter site somehow, and presumably that's via the same Internet with the same latency that the use of SW is trying to avoid.

What am I missing?
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I think they'd use a Part 90 link (i.e., UHF) from where the business is conducted to the HF transmitter, since the proposal is for a Part 90 service.
 
Mark Roberts said:
These guys wouldn't be doing it if it didn't work.
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Sure, there are people all the time who don't understand the limitations which involve physics, radio propagation, or data transmission. There is a long track record of failed ideas utilizing the MW or SW band. AM stereo comes to mind, portable ATSC 1.0 TV's, AMAX, and the idea of using ATSC 1.0 or 3.0 signals for two way wireless Internet.
 
Mediafrog+ said:
Are you talking about Radio Havana Cuba or Radio Cairo?😂🤣
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Cairo sometimes has modulation.. that sounds like aliens are taking over the transmitter at 150 percent modulation as it flees the sand
 
Kelly A said:
Sure, there are people all the time who don't understand the limitations which involve physics, radio propagation, or data transmission. There is a long track record of failed ideas utilizing the MW or SW band. AM stereo comes to mind, portable ATSC 1.0 TV's, AMAX, and the idea of using ATSC 1.0 or 3.0 signals for two way wireless Internet.
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That said, this is a cohort of people with substantial resources who already have been using experimental licenses for this purpose and who are drawing on that experience in their agitation for this rulemaking. Could they be wrong? Possibly. Sometimes theory doesn't play out in the real world, and that particular form of traffic goes both ways.
 
Mark Roberts said:
These guys wouldn't be doing it if it didn't work.
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How long have these guys been operating under an experimental license? Long enough to determine what happens when the sunspots tank (we're getting close to a peak now, so it'll be another 5-6 years). How and how often do they change frequencies, and is somebody actually listening in order to determine band conditions and what frequency to use?

This is shortwave radio nerdity at its most basic, not the stuff of guys in 3-piece suits, and any experienced ham or broadcast engineer worth his license will know how it works. I hope they hired engineers that are experts in RF propagation and the equipment they use can change frequencies as necessary. I have to guess that they did, but when it comes to money... o_O

And even if this system works, is it really capable of replacing the internet? Maybe as a backup system, but I don't see it as primary.
 
FROM THE PROPOSAL (No RM number assigned yet):
The SMC members do not seekto amend parts of the Commission’s Rules that pertain exclusively to, nor do they plan to utilize spectrum allocated exclusively for, amateur, maritime, or aeronautical services.
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Part 90 only defines HF use for these services as 2-25 MHz, but not allowing them to use the above services' frequencies cuts a big chunk of spectrum out. The ITU would have a lot to say about that if they tried.

 
KeithE4 said:
How long have these guys been operating under an experimental license? Long enough to determine what happens when the sunspots tank (we're getting close to a peak now, so it'll be another 5-6 years). How and how often do they change frequencies, and is somebody actually listening in order to determine band conditions and what frequency to use?

This is shortwave radio nerdity at its most basic, not the stuff of guys in 3-piece suits, and any experienced ham or broadcast engineer worth his license will know how it works. I hope they hired engineers that are experts in RF propagation and the equipment they use can change frequencies as necessary. I have to guess that they did, but when it comes to money... o_O
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Don't forget that the whole setup has to be automated.

Michael Lewis's Flash Boys: A Wall Street Revolt does a far better job than I could do in describing the lengths to which high-frequency traders (frequency as in how often, not as in RF) have gone to get an edge, including laying their own cables and bypassing the Internet altogether.

I am not as dismissive as some, skeptical but not dismissive.
 
I'll keep this brief because it's late, but I have two things to say about this:
  1. I don't think it's going to work.
  2. Don't they have anything better to do, like, say, fixing inflation?
c
 
cc333 said:
I'll keep this brief because it's late, but I have two things to say about this:
  1. I don't think it's going to work.
  2. Don't they have anything better to do, like, say, fixing inflation?
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Well, when you think about it; how much money and effort is spent on developing and marketing male sexual enhancement medication, or 'straightening', versus curing diseases that actually kill people? Speaks to societal priorities.

I worked with a group about six years ago who were testing a similar stock trading idea via radio. Instead of useless shortwave, they were testing on 460Mhz and something like 4Ghz. The idea is these systems transmit stock data via systems set up centrally in a major market. In my example; Washington, D.C. Both companies closed up shop because the data latency and subsequent interest by potential customers were less than lukewarm.



 
OK...let's say shortwave broadcasting finally goes up in smoke. Even China goes bye bye. WHAT happens to the 25 mhz of spectrum? If you don't think stock information and business services won't work, what will? Turning 49 meters into a new ham radio band?
 
crainbebo said:
OK...let's say shortwave broadcasting finally goes up in smoke. Even China goes bye bye. WHAT happens to the 25 mhz of spectrum? If you don't think stock information and business services won't work, what will? Turning 49 meters into a new ham radio band?
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Good point.

The band is pretty much useless for anything other than traditional communication, whether voice, CW or some kind of digital mode and new things like realtime trade data, so I guess if this doesn't work, nothing will, and the band will simply go extinct.

I guess I just took exception to the idea that the vulture venture capitalists (they are probably most likely to want to get that extra millisecond of edge over everyone else) are trying to take over yet another thing. I mean, they've had unnerving levels of success infiltrating everything else practically (housing, healthcare, automotive sales, maintenance and repair, veterinary clinics, and, most infamously, technology, to name just a few), and up until now, HF radio has been relatively safe from there.

What will it be next?

c
 
You sure Sprint and AT&T won't use that spectrum for 6G, 7G, whatever comes next?
 
crainbebo said:
OK...let's say shortwave broadcasting finally goes up in smoke. Even China goes bye bye. WHAT happens to the 25 mhz of spectrum? If you don't think stock information and business services won't work, what will? Turning 49 meters into a new ham radio band?
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Nothing. Just like the AM broadcast band, it's too small, too noisy, and hams don't use the bands they already have. Turn it back to nature.
 
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