ARRL FILES REGULATION-BY-BANDWIDTH PETITION

The other misleading piece here is the -18db S/N ratio. I'm sure P3 will work way down in the mud. It does so at the cost of speed, which is not mentioned in the post.

The primary point is that for an automated transmission of data, this is not a major thing. Pactor just repeats packets till the message gets through.

There are two major impacts from this, however. One, the spectrum is tied up longer thus denying the spectrum slice to other Pactor stations as well as other modes for longer periods of time. Two, if you should be using Pactor for a keyboard to keyboard chat it gets just as boring as other modes waiting for repeats to finish.

So it's kind of like saying that a 6khz wide SSB signal with pre-emphasis of the upper audio is usable down to 0db S/N. First, the spectrum efficiency is a lot less. Second, it's not very enjoyable. So why would you do it? It might be useful in emergency situations but exceptions should not count toward spectrum efficiency.

Just some thoughts.

tim ab0wr

 

ROFL!!

Ed,

The "sensitive error correction" along with the aggressive ARQ timeouts lets Pactor sit on a channel and tie it up for long periods of time getting through a message.

So what? It just ties up the channel making the spectrum efficiency even less because of the time denied factor.

And of course SSB doesn't have any error correction. Again, so what?

And if you need to run more power, so what?

As long as all stations using the frequency are experiencing the same noise levels and the conversations are an S-unit or more apart (e.g. a 600 mile or more skywave attenuation path), the spectrum efficiency stays the same.

And crest factor arguments are totally void? In YOUR dreams, perhaps. "Flight delay" doesn't change the crest factor of the signal being transmitted.

Frankly, it appears you are just throwing out "facts" in the hopes that somehow you can convince someone that Pactor is more spectrum efficient than SSB. For the most part your "facts" are not related to the subject at hand at all. In fact, it's not obvious that they are even related to themselves.

It *is* obvious that you didn't bother to read the FCC definitions for spectrum efficiency - at least you didn't read them for meaning. In their definition spectrum efficiency is NOT how far down in the noise a mode can operate. If you'll look, their definition doesn't mention Signal to Noise ratio at all.

Go back and read the definitions I posted for you. I didn't put them on here as practice in cut and paste operation. I put them out so we can all use a common definition that the FCC understands.

Climb a tall tree in that digital forest you are stuck in and take a look around. You'll see it is just a small grove of trees in a much larger forest. While most of that forest may be much older than the part you are in, that doesn't mean the biggest part is dying out or that it is inefficient in converting sunlight to energy. In fact, it may be more efficient and that is why the grove you are in only makes up 10% of the entire forest.

tim ab0wr

 

I'm not sure there was any misdirection. I'm a little reticient to say what it does look like. I've got the barn boots out and ready to put on tho!

tim ab0wr

 

Keith,

Isn't debate wonderful.  I can't find one thing in your post to argue with.

I like the propogation emails and the equipment tests, and I even got the family the ARRL study books as opposed to Gordon West because they have actual stuff to learn in them, other then tricks to memorize the answers (Sorry Gordon).

I think you are right, in that I think I would better spend my time to recruit new members to "throw the bums out", then to get rid of the ARRL.

The real issue is that we shouldn't replace one set of complex regulations, with another set of complex regulations.

The ARRL should approach this by getting a consensus on a workable bandplan first.  Then we propose to the FCC 6Khz across HF, higher bandwidth as the frequencies go up.  

If we can all agree (a challenge) that a bandplan will work, then we don't need to have bandwidth regulations that are just as restrictive and even more complex then the mode regulations that we have now.

That is the problem I see.  On one hand we say we have too many restrictions, and we can work it out, but then we just add, too many new restrictions, and the robot can of worms.

By proposed bandwidth regulation, digital can go up where ssb is, but ssb can't go down where digital is. Is that flexible?  What if people get bored with digital, and all the new no-code HF users like SSB?

In any case, it will be interesting to see how it plays out.  Next time around, everyone will be ready for some compromise.

73 - W6NJ[/QUOTE]
Yes, I think we are in "violent agreement" here.  And you have also brought up another very important point.

I wholeheartedly agree that getting things in the right order (i.e. consensus on a "workable" band plan FIRST and THEN submitting a proposal for 6 KHz bandwidth, etc.) is going to be one of the critical keys to making it all happen without also tearing the US part of the hobby apart.

I think we are also in agreement that none of this is going to be painless.  That’s because the "way it's always been done" (with the FCC micro-managing our sub-bands via regulation) has become so entrenched with a lot of us that it now borders on being "cast in stone".

On the other hand, taking the "lid" off too soon (or too quickly) without having a proven alternative band plan that's already been thrashed out well ahead of time (and that everyone can at least live with) would simply create more chaos.

I hope you are right that, "Next time around everyone will be ready for compromise".  

If not, we’re in for a whole heap of trouble!

73,

Keith
VA3KSF / KB1SF

 

OK Keith --
Where you said this --

I know my own 10-year plus, volunteer leadership role with AMSAT offered me a fantastic opportunity to have a major, lasting impact on issues of critical importance to at least one part of Ham Radio’s future…much more so than if I’d simply been content to just talk about them at the time.  


Now that you are unfettered by leadership issues in your time at AMSAT, will you be participating in filing formal Comments if the proposal from Newington is allowed to move ahead?

I remain puzzled that your participation has not risen to the level of individually working with the regulatory body that governs our activity. It's not duplicative; it does not burden the system as you suggest; indeed the FCC has created the Electronic Comment Filing System to elicit comments from active, involved Amateurs and (unlicensed) outsiders hoping to join us.

Although you say you've achieved "major lasting impact" in your activities within one specialized area of the hobby, you have chosen against contributing personally to the rulemaking that can constrain or encourage the broad range of activites in the Amateur Service.

Maybe you'd like to explain further, or perhaps you can rationalize to yourself why you are content to stay within a bolloxed system represented by a moribund little non-profit group in Newington.

It's nice that you want to help them, and many of us are also trying to save them from themselves, long before your call for us to join you. But there are other ways to achieve an efficiency of energy spent to yield a significant result, that being the growth, nurturing and assurance of what we enjoy in the Amateur Service.

Paul/VJB

 

It really doesn't matter what the current petition does (or doesn't) say.  Even with all its flaws, it's simply a "trial balloon" whose primary purpose has probably already been served.

Just like the ARRL’s “restructuring” petition that’s (so far at least) gone nowhere, I believe this particular petition is going to also go straight into the FCC’s wastebasket…if it hasn’t already.

I'm still convinced the main purpose of the ARRL’s current bandwidth petition was simply to get the FCC geared up internally so as to be better prepared to address the issue at a future time…a time when we’ve got our own collective acts together.  In fact, I wouldn't be at all surprised if the initial request for such a filing came from within the FCC itself.

It's time to stop beating this (very) dead horse and move on.  We need to start thinking and planning for the time when we’re going to be given the responsibility for doing this exercise for real.

73,

Keith
VA3KSF / KB1SF

 

Keith,

I must agree with most of your theory about this filing, but I think, like Albert, that it is premature to dismiss this ARRL filing as a "trial baloon".  In its current form, without any hint of a bandplan, or even a method for creating one, this proposal is a major threat to the amateur radio service as we now know it due to the many flaws already pointed out many times.  We must focus our effort towards assuring that this bird cage liner never makes it beyond the comments period.

Then we should restart the process and get it right.  A proposal, including a bandplan seems to make sense as the right approach.  I believe support could be obtained for a sensible solution that doesn't punish the majority nor overburden everyone with excessive regulation.  Sadly, this concept of cooperation is not understood in Newington.  They haven't even figured out the communication part yet, as they still talk to only themselves regarding critically important matters regarding amateur radio.

73,
Luke

 

AB0WR:"Now, according to Single-Sideband Systems and Circuits by Sabin & Schoenike on Pages 18-20, the typical peak-to-average power of speech is around 14db (thats a peak-to-average ratio of around 25:1).

The crest factor of a Pactor III signal is 3db to 4db according to SCS specifications. That's a peak-to-average ratio of around 2:1.

(as a comparison, I believe MT63 has a crest factor of about 4db or 2.5:1, very similar to Pactor III)

So a 100watt PEP SSB transmitter modulated by a typical voice will run about a 4watt average output. On the other hand, a 100watt PEP SSB transmitter modulated by a Pactor III signal will run about 50watts average output.

It should be obvious why you can mix multiple SSB voice conversations on a frequency using propagation stacking while this is prevented by the Pactor signal."

Tim,

A 14 dB peak to average ratio for SSB sounds reasonable. I have measured to peak to average ratio for Pactor III at 9 dB with ARQ pauses and 6 dB without the pauses. MT63 has a peak to average ratio of 9 dB. I am wondering how the capture effect for digital modes plays into the propagation stacking? I have not measured the capture ratio of PIII or MT63, but I am sure the capture ratio is not infinite. I think you are assuming a infinite capture ratio which means that a decoder can never discriminate between 2 or more signals. I know that there was some testing by MARS operators using voice SSB and MT63 simultaneously on the same frequency. Both the voice and the MT63 were decoded without error. I have seen multiple MT63 signals on the same frequency, and my decoder was able to capture the strongest signal; however I did not quantify the capture ratio. I don't know of any testing like this for PIII, but it would be interesting to prove that PIII (or any other digital signal) and voice cannot exist on the same frequency simultaneously using your theories. It may not be comfortable listening, but I am certain that both signals under the right conditions can co-exist.

73,

Mark N5RFX

 

Luke thank you, this is what I am getting at with Keith's attention shifting toward troubleshooting the group in Newington by only working within.

He deserves time to respond, but he's not the only one to pay homage to a group that seems to deliberately go out of its way to irritate the broader Amateur community.

Talking, as we are doing here on QRZ.com, may not have value to folks like Keith (although he's spending considerable time here too), who has uttered calls to press the League to re-direct its actions, instead of taking charge with other people who share views.


This forum should serve as a pattern for the League in its deliberations. The crop of volunteer and paid leadership has steadfastly refused to allow such a conduit.

So, we are left to develop a challenge to the Newington bandwidth scheme, and to provide constructive alternatives, including proposals within the current system to accomodate nascent "digital" modes for quite a while to come.

Independent thought is a good thing Keith.

Paul/VJB

 

Keith,

I must agree with most of your theory about this filing, but I think, like Albert, that it is premature to dismiss this ARRL filing as a "trial baloon".  In its current form, without any hint of a bandplan, or even a method for creating one, this proposal is a major threat to the amateur radio service as we now know it due to the many flaws already pointed out many times.  We must focus our effort towards assuring that this bird cage liner never makes it beyond the comments period.[/QUOTE]
Luke, I would be extremely surprised if it does.

That's because it was precisely the issuance of such a "call to action" that was the intended result of the petition being filed in the first place.  The FCC/ARRL (et al) wanted to shock us into getting up off our finals and begin seriously thinking about how we want our HF bands to look once the FCC gets out of the HF sub-band regulation business.  I can't think of a better way to do that than to float such a "turkey" as what the ARRL as now filed with the FCC on our behalf.  

So, in that sense, I believe the original intention of the filing has now been very much fulfilled because both the League and the FCC have, indeed, gotten our attention (not to mention raising our ire!) on the matter.  There’s nothing like anger (or the fear of losing something “near and dear”) to motivate people to action.

So, it seems to me, the ball is now back in our court.  

It also appears (at least from the many posts here) that we are (thankfully) beginning to seriously focus on the future and how we want our bands to look down the road rather than obsessively fixating on the way things “have always been done” in the past.

That, too, is a major accomplishment.


73,

Keith
VA3KSF / KB1SF

 

Paul, I couldn't agree more.  

And I also believe it's just this type of "independent thought" that is now coming to the fore and which will be sorely needed to help us see our way beyond the ARRL petition.

73,

Keith
VA3KSF / KB1SF

 

Woo Cowboy,

I have never been this peeved at the ARRL.  Did you read the "throw the bums out" part?

I don't support this proposal one bit, and never have.  I have been butting heads on this issue for over a year.

I will be doing my best to send this proposal into the waste basket.

Sorry Albert, but I don't get your point.  I have had a few exchanges with Keith, where we definately didn't see eye to eye, but I'm not going to disagree just for the sake of it.

Read again.  It says "bandplan first", then a "NEW" proposal.

I live in Colorado, hunt and fish, and the closest thing I have to Tie-dyed, are camo cloths for predator hunting.

Geeze......

73 - W6NJ

 

Albert,

I wasn't offended. I thought is was funny. I've blasted Keith a few times, and it is interesting to find some common ground.

The only thing that offends me are the arrogant folks at the ARRL that don't give a damn what we think.

But we will see who wins this battle.

73 - W6NJ

 

Mark,

These measurements seem a little high based on everything I read. Of course, the actual crest factor is going to be somewheat dependent on the actual data being transmitted and how it winds up being coded. The crest factors quoted for Pactor and MT63 may be what the ideal is expected to be. Reality could very well be different.

I have not read any place of capture effect being seen with the protocols such as Pactor and mt63. I am not well versed in this area. I thought capture effect was primarily seen in protocols doing collision detection among multiple users and was highly dependent upon how the signal is decoded and handled in the receiver. Since neither Pactor or mt63 do collision avoidance detection it has not been anything I've ever researched.

I've always assumed that the effect stemmed from the fact that somewhere in the receiver a circuit like a frequency discriminator (e.g. used with FM) was in use that would tend to lock onto the zero crossings associated with the strongest signal. I've not seen this addressed with Pactor or mt63. Since both of these are FSK signals it is possible that some capture effect could be seen.

Do you have any documentation available that speaks to capture effect being seen with Pactor and/or mt63? I know from empirical results gleaned from listening to lots of Pactor sessions that it isn't very often that two Pactor sessions can be run on the same frequency without them interfering with each other unless the S1 and S2 signal strengths are vastly different. Especially with Pactor I, hijacking of a session by the ARQ packet from another session is common. I see it happen all the time.

I suspect that if the capture effect was very significant you would see multiple Winlink stations sharing just a few frequencies rather than doing a horizontal channel spread like a fat lady sitting on a bleacher seat.

I don't want to sound like a smart-a** but if your decoder will only lock on the stronger signal then how can multiple sessions share a channel? If the stronger signal "captures" the receivers, the modes still run a lower spectrum efficiency than SSB.

I've listened to a lot of Pactor III while running my DNTS node. If the pactorIII signal was consistently 12db (2  Sunits) lower than the SSB signal, you might be able to share. (The 12db is the 6db S/N ratio needed for a good  articulation ratio plus 6db for good dynamic range) Like you say it won't be comfortable - I would even say it would be painful It would be interesting to test this in high noise and low noise situations.

This would still lower the spectrum efficiency of the area where shared use is seen. You are down from three SSB conversations taking place on 3920khz at the same time to a SSB and a pactor session. You've just cut your spectrum efficiency by a third. Is that a good thing?

However, I suspect the Pactor signal is going to be very badly compromised by having to maintain a level of 12db lower than the coexisting SSB signal. Yes, pactorIII may be able to operate down to -18db S/N but it does so at a very reduced throughput rate. That is never mentioned by those crowing about how low it can go into the mud. It requires multiple packet repeats for the decoder to build up a good packet and in a situation like this it is possible for the error detection to be fooled and a bad packet to make it through. It doesn't happen often but it does happen. It happens more often when you are working down in the mud all the time. This is also based on random noise. A coincident SSB signal that is not random noise could "capture" the decoder at times resulting in even more lost packets. It would not be an ideal situation to be in at all.

The bottom line is that if it is "uncomfortable" to share then why recommend it? Why not just open up a digital anything-goes 3.5khz area and let the digital modes fight it out? Refarm the Novice sub-bands to digital anything-goes 3.5khz preserves and let's see where things go.

tim ab0wr

 

Me too...

The XYL (5wpm extra) just mentioned how it would be nice to work other cw stations that are slow.

Those days are gone, when I worked the 40 meter novice band in the seventies night after night until 20wpm was easy. So just open it up to the digital wars, and let the rest of us go about our business.

By the way Albert, it was interesting to see that you shoot pistol competition. Do you shoot 45ACP?

The wilderness that you described here, is hardly that, and the same lack of hunting land is simular to Maryland. I was born in PA, and spent my years in Hagerstown and Baltimore, before moving to OK in 1970.

The ringnecks are much bigger in your area, then here.

But the Elk are another story, and if lucky we can get two a year.

73 - W6NJ