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Old 09-06-2020, 16:18   #106
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Harry,

I understand your question / dilemma....wanting to use what you have, not spend money on something you don't need, and/or you're unsure of what you need...
{and, btw, yours are very good questions for this thread!}


Up front, the quick and dirty answer is:


The details to follow notwithstanding, for your application, I don't see any reason your M-710 shouldn't work for you....(no need to buy a new radio....well, not yet anyway)

The details of what / how to use your M-710 can be found down in #5....but, I do hope you read all of this, watch the videos I reference here, and, then read #5....and then the radio manual I reference at the end...



~~~~~~~~~~~~

Before we get started on the details, please accept this fact as an absolute:

Successful HF communications (of all types) is all about the received Signal-to-Noise Ratio (S/N)!!
The higher this ratio, the better....and the more successful your communications will be...
That's what it is all about!
No BS....that's it!



It's in the "how to maximize the S/N" that the details come out....high on this list is:

a) radiowave propagation expertise....the operator knowing what band/freq to use for a specific time-of-day and specific communications distance...[operator experience / expertise is still tied with "antennas" and "eliminating receive RFI", as the most important parts of the HF communications system, even with modern 21st Century radios] Fyi, operator knowledge of radiowave propagation has been all but eliminated by use of multi-freq HF-DSC signaling...



b) reducing / eliminating sources of RFI nearby (typically within 1/4 - 1/2 mile) your antenna / radio (on our boats that includes everywhere on-board)



c) improving antennas / antenna system (for us, this is almost all improving the transmit antenna, 'cuz we don't have the room for separate receive antennas, but proper grounding helps both transmit and receive)


d) having a radio that handles noises well, and use of headphones, etc....and overall operator experience / expertise, etc...


If you accept these as absolute facts, watch the videos, eliminate on-board RFI, etc....you should be successful...
~~~~~~~~~~~~



1) BTW, I know that my detailed instruction videos are M-802-based....and although they may look M-802-centric, the generic "how-to's" of Maritime HF Comms and Offshore Weather actually apply to all HF radios.


Please have a look at these playlists....

Maritime HF comms (except for the videos here regarding HF-DSC comms, these all apply to the M-710, too)
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y



Offshore Weather
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2mPZAx2vWzdjTJjHlChruyY






2) So, in your case, you can use what you have....but, you just accept its limitations....and unfortunately one of those limitations is the fact that the M-710 is a marine radio, not a ham radio....not a bad thing, but maybe not what you want to hear?
(oh, and it's also an older, non-DSC marine radio....but, for your application / your proposed cruise, this shouldn't be much of an issue)


Harry, please forgive my bluntness, but....but, if you're ham that hasn't ever used a radio, the M-710 is not really the radio you want to learn on....but, if you wanted to learn old marine radio use, then it's darn good!!


You see the issue here?
It is the radio you have, and we should encourage you to use it, it's just not really the radio you desire (based on what you write)....usable for ham, but not great for ham use.....and usable for some marine radio use, cruising nets and hopefully raising the USCG, but not well suited to 21st Century marine HF comms....

So, yes....you can use what you have (see details below), but accepting its limitations also means that your learning is going to be different and possibly frustrating....
Again, this doesn't mean you can't do it, nor that the M-710 is a bad radio, it's just that it is not a ham radio, and is not a great radio to learn ham radio with...





3) I will give you a few more hard facts (and advice) that should help you out, but first a tiny bit of context/opinion, in response to those sailors that buy a new laptop every few years, a new smartphone every couple years, and/or some spending $$$ on cellular/wi-fi, and even satcom systems / sat phones, but still won't buy a new radio....if that's okay?

{please understand this isn't about you / your application...this is just a way to explain how / why things change in the world of "radio"}



The Icom M-710 was a good, hi-quality, well-made, and excellent performing maritime HF Voice (SSB) radio, designed about 30+ years ago, and sold about 15 to 30 years ago...and for that specific intended use/application, at that time, it was good...very good! It was not a ham radio, and was never intended to be used as a ham radio, nor was it ever intended to be a DSC radio...it was a good HF SSB (voice) marine radio, damned reliable and darn easy-to-use as a Marine SSB radio....and that's it...



Looking at the generational changes in tech.....think about this in terms of what you're reading/typing these questions on....do you still own/use an 80486 machine (or even a later 80386 machine) with processor clock speeds of 16mhz up to 33mhz, running Windows 3.1? (or maybe an original Pentium, at 75mhz?...running Windows 95?)....with a floppy disc drive, etc...

{I know, I'm on last year's laptop, with a 6-core/12-thread processor at 2.6Ghz(2600mhz), with 512G SSD, 16GB RAM, running Windows 10....and, I wouldn't consider looking back at an older computer and wondering why I I'm not using the older (but, perfectly functional) computer...}

Or how about watching TV on an old analog / CRT TV??
Or, watching movies on VHS videotape??
Or listening to 8-track or cassette audio tapes??

Or, would I try to use a mid-90's Motorola 3200, or Nokia 1011, or 9110 cell phone??
Motorola 3200 (from 1992)


Nokia 1011 (from 1994)


Nokia 9110 (from 1998)




You could still run some programs on an old 386 machine, or play a few games....or send an email, etc....(heck, I still have a fully functional 75mhz Pentium machine w/ Windows95....but haven't even turned it on in 20 years!)....
But, is anyone doing that....and is anyone advocating that??
I don't know any, but I could be wrong....


Now, I understand this sounds absurd....and I'm not seriously saying that using an M-710 is like using an old '386 machine on Windows 3.1.....nor like trying to use a 20+ year old cellphone....
No, I'm not saying that!



But, I am trying highlight the fact that just because Maritime HF radio communications (particularly ship-to-ship, and/or Distress/Mayday calling) doesn't rely on normal "infrastructure" for effective communications, we forget that there are generational changes in how our words (voice) or messages (text) are sent/received....
"Radio" might be slow to change, but change it does!! And, if we want to be able to use those services / features, we need to change too...


{The day of "spark" transmitters, faded as keyed-CW / keyed coherent carrier came onto the scene (1910's to 1920's)....then we had what many then just called "radio" (AM modulation of RF carriers), and this held, even in maritime communications into the 1950's, when SSB, etc. came on rapidly....(and during the 20's thru 50's we also had forms of radio-teletype).....and in the consumer world we had "FM Radio" (broadcast FM radio) and "UHF TV" (broadcast UHF TV)....all of these generational changes meant that those wishing to use/listen these new things (like they used to use/listen-to in the past), needed to buy and use new generations of equipment....sure you can still use an old AM broadcast radio (MW broadcast radio) to listen to some stations, but you can't use it to listen to FM radio stations....same for trying to use an old AM marine radio, to communicate with SSB radios...}

DSC, and here in particular HF-DSC, is another generational change in Maritime Communications....

(and, fyi, yes I'm still surprised at how many of my fellow sailors balk at this....and refuse to accept a change that we all knew 28 years ago, was coming....and that we all knew was mandatory for SOLAS vessels and all signatory nations, effective 21 years ago...but instead of accepting this change, just ignored it, and bought a new smartphone every couple years....I still don't get it, but no worries....it's kinda a moot point here.)

Now, to be clear, the GMDSS is a worldwide system designed by international committee SOLAS / IMO (in late 1980's), and revised and early implementation in 1992...and made mandatory by all 160+ signatory nations and all SOLAS-grade vessels, by Jan 1999...

Part of the GMDSS is DSC....VHF-DSC, and MF/HF-DSC....and elimination of any Voice Radio radio-watch-standing requirements, replacing this "voice radio" watchstanding with DSC scanning/monitoring...


Icom (and others) needed to make new radios!
[Enter the M-802 in late 2002 / early 2003]

And/or try to adapt their older radios.
[Enter the Icom GM-110 DSC Controller, in mid-90's thru 1999]
I heard two different stories about the GM-110, one from an engineer at Icom Japan, who mentioned he didn't have an exact number on production, but assumed it was just a few dozen, maybe up to about 100? (he also said they had less than a dozen prototype and beta test units).....the other story was from an old acquaintance at Atlantic Radiotelephone who said he actually saw one, once...

So, the chances of you finding a GM-110 is slim...sorry about that...



Now, while I know playing with computer-control of radios, especially SDR's, is becoming a fad these days in ham radio....and that's fine...
But, at sea / offshore, I have yet to see/hear of anyone doing this...

And, when it comes to DSC for most of us cruisers, our primary concern/use is for Distress signally, and/or a secondary form of Distress signaling and THEN two-way voice communications with RCC's / search-and-rescue personnel....
So, I cannot see anyone using a laptop in times of distress, trying to send / receive DSC calls....
(I know some think there is no reason to "buy a new radio", when their 20 - 30 year old radio can be adapted / controlled to do what they desire from a computer....but, I'm not seeing this as a viable option for actual DSC comms, when offshore / in remote locales....to play with, in port or on-shore, sure...but at sea, especially in heavy weather, no...)




4) Now, computer control to make the M-710 easier to use on the ham radio bands, this has merit....and, whether you use fldigi, HRD, etc., you may find the M-710 to be adequate for your ham radio uses?? (if all you desire for now are some "cruising nets" and some weather forecasts, and of course safety/distress comms....then the M-710 should be fine for you, along the "Down East Circle"...)



But, my if what you're trying to accomplish is an easy-to-use ham radio, where you can find lots of folks to talk to, etc.....then, you're likely going to be buying a new radio....But, you can use the M-710 for some of this, just not as easy-peasy or casual as you might like....


If you program it right and learn how-to use it / learn HF communications techniques / learn radiowave propagation....you might be good-to-go!



To be clear, one of the great things about the M-802 for many sailors / cruisers, is its easy / seamless ham radio use....and unfortunately the M-710 isn't easy-peasy nor seamless for ham radio use....sorry about that..




5) So, with the above context and facts understood....what can you do with your current M-710?
Well, you can do a lot!!

Verify some channel programming, and/or program in some frequencies that will be useful....and your M-710 should be good for you / your planned cruise....(just be sure to eliminate your on-board RFI and spend some time learning how-to use the M-710 and "learning HF radio"....learn HF communications techniques / learn radiowave propagation, and you'll be good-to-go!)


--- Verify what channel numbers you have 4125, 6215, 8291, and 12290khz programmed into...these are your SSB Voice calling and Distress frequencies (that luckily are still monitored by the USCG)....
https://www.navcen.uscg.gov/?pageName=cgcommsCall


Please be sure to watch the seventh video in this playlist for details on these!
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y



--- Verify what channel numbers you have USCG HF "working channels" (ITU 424, ITU 601, ITU 816, ITU 1205, etc.) programmed into....these will be the channels that the USCG broadcast Offshore and Hi-Seas Voice Weather Forecasts on...(but, these are NOT monitored by the USCG, so you do NOT use these frequencies to call them....use the freqs above...4125, 6215, 8291, 12290khz, to call them, and others...)

https://www.weather.gov/marine/uscg_broadcasts



--- Verify the channel numbers you have various "cruising nets" (ham and maritime) programmed into....these will be the channels you'll find useful to communicate with your fellow cruising sailors and exchange info, ask advice, etc...(particularly 7268 and 14300 on the ham bands, and 8152 and 8104 on the marine bands, as well as 4a, 4b, 4c, 6a, 6b, 8a, 8b, 12a, 12b, and 12c....see all these freq details in one of my earlier posts here, post #78 above!! )

http://www.docksideradio.com/east_coast.htm




--- If you wish to download JvComm32 (free software) and try reception of HF WeFax (Weather Charts broadcast by USCG), please be sure to verify what channel numbers you have the various USCG WeFax stations programmed into....and, you'll be able to get the "gold standard" of offshore weather forecasts, updated 4 times a day, for free!

All you need is a cable from the M-710's headphone or speaker (or even better the fixed-line-level audio out from the M-710's rear acc jack), going to your laptop mic/line input, tune the M-710 to one of the WeFax freqs, and use JvComm software....


https://www.weather.gov/marine/uscg_broadcasts


https://www.weather.gov/marine/marsh
https://www.weather.gov/media/marine/hfmarsh.txt


https://www.weather.gov/marine/gulf
https://www.weather.gov/media/marine/hfgulf.txt




BTW, the CCA has a nice (older, but updated 10 years ago) operations manual for the M-710.....that should help you out with the 710's programming, etc....but, please watch the videos/playlists referenced above first....and then have a look at this....
https://wwww.cruisingclub.org/pdfs/com_emercard_icom_m710_m710rt.pdf





I hope this helps...

Fair winds...

John



P.S. I had to Google "Down East Circle"....
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Old 09-06-2020, 17:36   #107
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Reading a couple of posts above about failure modes... NMEA 0183 is very robust. This is just a serial connection, widely used in computers, military, etc. Seatalk 1 is built on top of the serial connection too. It is very unlikely to fail. This is akin to saying what happens if my GPS antenna connection fails or if my depth sensor wire fails.

Nmea 2000 is also robust but one can make the case that because it requires its own power supply that can blow a fuse. Unlikely but possible. I would not worry so much about the networks failing. Better invest more time in designing a good network, crimping the connections and securing the wires.
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Old 09-06-2020, 19:01   #108
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

John,

I find your HF knowledge and guidance invaluable on this forum, highly appreciated. I have learned a lot. If I may just update some of your statements because things have changed in the last couple of years:


Quote:
Originally Posted by ka4wja View Post
...but, if you're ham that hasn't ever used a radio, the M-710 is not really the radio you want to learn on.
The M-710 is a fine radio for both marine and ham use. Very few people use ham radio as in the past, manually turning the dial. These days, it is all digital, all under computer control. The radio is just a data to HF modulator with a keypad to use in emergencies. The rest is all done by computers. This is how military HF radio is used, this is what modern hams use it today.


Quote:
Originally Posted by ka4wja View Post
Looking at the generational changes in tech...
HF radio has not changed much since the 50s... temperature controlled oscillators appeared in the 80s in consumer radios - this was a generational change because it allowed many more digital modes of transmission such as Pactor. Yet, it is totally not necessary for HF DSC which is a Sitor based mode developed in the 19050s. It requires very little either from the radio or from the controller/computer). A few years later radios started getting DSPs (digital signal processors) that massively improved noise reduction capabilities. Around that time HF DSC was mandated and radios like the M-802 appeared. The DSC coder of the M-802 is a very crude one, difficult to use, does not support the entire DSC message set, basically nothing to brag about. The 803, as we know is not much better. Recently, HF radios appeared that have wide IF, where you can see the entire band on the spectrogram which is very nice visually if you are hunting down difficult contacts. Not that useful on a boat unless you plan to do HF contesting while at sea. That's about it. I would love to have an HF radio with built-in Pactor, ALE, Selcall and DSC and some cool 110A waveforms but it does not exist in the commercial world. Yet, with a simple $99 tablet you can have all of this today with any HF radio that has a temperature controlled oscillator and enough bandwidth (with minor limitations but OK).

Quote:
Originally Posted by ka4wja View Post
So, I cannot see anyone using a laptop in times of distress, trying to send / receive DSC calls....
It is a fair statement how you personally feel about computers at sea but in this case, you would need to agree that cruisers should not be expected to use HF+Laptops to send and receive email at sea or in heavy weather or to download weatherfax. Yet, many cruisers do exactly that, every day.

Sending an HF distress signal, either using PersonalDSC or my script, arguably takes less time than on the M-802. You need to boot the computer or tablet, launch the app and click one button. When you get a response, you will immediately be able to see graphically the distance to the responding CG sector, the distance and direction to nearby ships who may acknowledge the call as well, their size, type, photo, etc. direction. Is it very different from just getting a bunch of coordiantes on the M-802. I agree that a GMDSS compliant radio has additional benefits such as going through the distress frequencies automatically, etc. but it is just a couple of more clicks.

Quote:
Originally Posted by ka4wja View Post
Now, computer control to make the M-710 easier to use on the ham radio bands, this has merit...if what you're trying to accomplish is an easy-to-use ham radio, where you can find lots of folks to talk to, etc.....then, you're likely going to be buying a new radio.
Again, the way we use the radio has changed. HF email apps (Airmail or Winlink) use computer radio control to automatically select the best frequency for establishing contact. It is so much easier than entering the frequencies manually. Radio nets have fixed frequencies that you can either program in the radio (difficult, needs instructional videos, people forget) or you can just store them in your address book on the computer, so that you can check the propagation conditions before joining a net. If you want to update your stored frequencies in the radio with your app address book, you just hit download and it does 1,000 updates in less than 2 minutes. It does require basic scripting but most hams do it.

Quote:
Originally Posted by ka4wja View Post
If you wish to download JvComm32 (free software) and try reception of HF WeFax (Weather Charts broadcast by USCG)
I have nothing against JVComm32 but it is old. These days it is so much easier to either use the integrated fax receiving mode of fldigi or the other radio control apps or just use an app on the iPhone or the Android device (HF Weather Fax is a good example). It costs $2.99, you can plug any cable into it (or go the bluetooth route I have talked about before), the phone uses minimal amount of power (you can leave it on 24 hours/day).

My view is that HF radio is hard because of the required RF knowledge and all the caveats in installing the radio right. However, once installed, it is all computer driven nowadays. Very few voice communications.

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Old 09-06-2020, 20:35   #109
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Wow. A lot of good information, and a lot for me to digest, as I get time.


I should have added a couple more details about me. I am a licensed engineer -- mechanical, but with a lot of course work and experience in more of the electrical side of things. It doesn't make me know more, but it does make it easier for me to learn more. I'm also a rather competent self-taught computer geek. I've even taught myself 8088 assembly and written a few fun little programs. Somehow, my knowledge has fallen behind the current status, and I can no longer program a macro in Word. Ah so. But all of the info on this long thread is stuff that at least I'm capable of learning.


Most of your comments I'll have to read and digest a few times. But I do want to directly answer a few from Auspicious.


* I'm interested in the outboard DSC, although KA4WjA has indicated that might be dreaming. I'll get a picture of my label.
* I do have a General license, KC3IAF. General was easy enough, Extra seemed more work than the value added for my use.
* I'll drop you a direct note. I'd love to get help and talk boats. I'm near Cantlers (Mill Creek, off Whitehall Bay).


Thanks all for the great information.
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Old 10-06-2020, 00:57   #110
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Quote:
Originally Posted by sailingharry View Post
* I'll drop you a direct note. I'd love to get help and talk boats. I'm near Cantlers (Mill Creek, off Whitehall Bay).
Got your note and responded.

I'm off Forest Drive along Harness Creek. My boat is in Galesville.
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Old 12-06-2020, 08:37   #111
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Harry,
You're welcome!

1) And, n case it got lost in my long-winded posts....I think your asking questions and willing to learn is great!
Good on you!
(and, sorry if some of this get overwhelming....just take it one step at a time, and you'll get it...)


2) Btw, as for "radio knowledge" / operator expertise....surprisingly to some, in actuality some of the most successful radio ops are rather poor engineers / fairly ignorant of a lot of the details of electronics, etc....of course they know the basics (in order to pass an Extra Class License test), but that's about it...
{passing the Extra Class is just the first of thousands of steps to understanding communications....although, some think once they made it there, they actually made it....what a ridiculous falsehood....you have nom idea how many "extras" are clueless!! okay, enough of a rant....sorry, just a peeve of mine... }

I'm serious here....some of the best multi-multi ops, are barely competent to pass the test, but have honed their operating skills and understand radio propagation like a NASA solar scientist....

The reason I mention this is that while I majored in physics and have worked in RF engineering / consulting (running my own firm) for most of the past 37 years, very little of what I learned in school or use for my clients transfers to modern HF communications operator skill / expertise....

As this skill / expertise comes with practice / experience....and to be honest, in some of us it is also an innate talent....


Bottom line, as I wrote earlier, HF comms is all about maximizing your receive S/N....

And while on-shore, "b" and "c" are about equal to "a"....

On-board, "c" (improving antenna system) is fairly moot here, 'cuz we are all on similar boats, and we have already accepted what is the overall best antenna system / antenna ground system......
And "b" is such an absolute that it almost goes without saying, that we on boats have it easy, as all we have to do is deal with a few RFI items on our own boats, and then we can be away from RFI sources....so...

So, we get back to "a" and "d" as being very big parts of the equation here!!
And, this is why I so fervently stress this as a vital/critical part of your HF communications system....that is you, the operator!!!
(and no, unless its a modern ALE system, a computer is not a substitute of an experienced operator!!)
Quote:
a) radiowave propagation expertise....the operator knowing what band/freq to use for a specific time-of-day and specific communications distance...[operator experience / expertise is still tied with "antennas" and "eliminating receive RFI", as the most important parts of the HF communications system, even with modern 21st Century radios]
Quote:
Fyi, operator knowledge of radiowave propagation has been all but eliminated by use of multi-freq HF-DSC signaling...

b) reducing / eliminating sources of RFI nearby (typically within 1/4 - 1/2 mile) your antenna / radio (on our boats that includes everywhere on-board)

c) improving antennas / antenna system (for us, this is almost all improving the transmit antenna, 'cuz we don't have the room for separate receive antennas, but proper grounding helps both transmit and receive)


d) having a radio that handles noises well, and use of headphones, etc....and overall operator experience / expertise, etc..

So, Harry, please do yourself and your family/crew the favor of spending the time needed to learn about all of this....'cuz it's not like swiping on a smartphone....it really isn't...
And, while when coming into to HF comms might seem both easy-peasy for an engineer, and at the same time confusing as something new, please know it's actually pretty darn easy to learn....and the more you do, the more you can do! The more you use it, the better you'll be!!

No need to be an engineer, nor a software geek....not in the slightest!!

All that's needed is some level of intelligence, an open mind (willing to learn and willing to believe that you don't know everything), and some time on-the-air!!
Forget about computers for a few....think more like a kid listening for the BBC on a shortwave radio....that'll put you in a better mindset to learn HF comms!




3) As for the GM-110, if you find one....I'll contribute $100 towards it, for you....just to see one and see one working....
(actually, that's not much of a gift, 'cuz I', fairly certain you'll find one in working condition...)


Fair winds.

John
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Old 12-06-2020, 08:56   #112
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

First off, please accept my apologies for having to go off on tangents here!! This is not necessary for you all to grasp, except that if you wish to use HF-DSC on-board, it's best (all but necessary) to have an HF-DSC radio....

And, that most ham operators do still turn a knob and talk to people!!! (I can't believe I actually need to write that...)

For the life of me, I cannot see how much of this ridiculous tangent (how many hams use their radios as radios, versus how many use it as a "data to RF modulator") is relevant to my fellow sailors??

(and, I suspect just us discussing this turns some of them off / away from ham radio....which is very unfortunate....and I'm truly sorry about....just cannot let this absurd myth propagate! )



1) To be honest, I just don't have the time to debate the differences of opinion here...everyone has the right to voice theirs, but I don't have the time to debate all of this over-and-over-again...

I'm sorry to be spending all this time on HF-DSC....it's not that I feel it isn't important to understand HF-DSC (it is), but just that I think it is waste of time (that I don't have), to debate this again and again...

I mean seriously, if you wish to experiment, write software, etc....that's great...and I assume this software is nice....but...

But again, in my opinion....advocating the use of 20 - 30 year old (non-DSC) radios, with a new $1500 - $2000 modem (your PACTOR modem), and a $99 computer, and your software (which I assume is nice), in order to utilize MF/HF-DSC, makes no sense to me at all...as you say it's just an FSK signal (1950's tech)...

{fyi, although the M-802 is now discontinued (replaced by the M-803), they are still available used for ~ $1000 or less (and some NOS), and on close-out this January the sold for $1500 new, versus the regular price of $1800....so, I never understood this approach to adapt older (non-DSC) radios for DSC use on-board....never made any sense to me, and still doesn't}


As I write, I have no problem with others ideas and opinions, we are all entitled to them, so no worries....I stated mine, along with what is the accepted SOP, and I'm done wasting more of my time on this...


2) And, if anyone finds a GM-110 at a reasonable price (~ $100 or so), I will buy it and send it to "sailingharry"....I just want to take pics of it, first, as well as have him take pics of it in operation, and exchange HF-DSC calls between us....now, I know this sounds generous, but I'm confident that they are made almost exclusively from "unobtainium"... LOL



~~~~~~~~~~~~~



3) Now that I'm done debating the DSC non-issue....I'd like to highlight another issue, that you seem to have a rather bizarre point-of-view on?

I'm an active ham, and have been so most of my life....and, while human nature suggests we are usually more comfortable using / discussing what we are used to, you know "familiarity breeds familiarity"

But, I'm sorry to say that the facts of how most hams use ham radio are vastly different than you state!





4) First, let's look at some radio stats....With about 3 million ham operators worldwide.... ~ 760,000 in US; ~ 450,000 in Japan; a few hundred thousand in Europe....I know that some 25,000 (20,000 as of end of 2018), IC-7300's have been made, as well as a few thousand other SDR ham transceivers (Flex, ANAN, 7610)....so, maybe 40,000 to 50,000 over all?



We are all aware of what can be done by connecting most modern ham radios to computers (sound card modes of operation, computer control of your radio, and some "point-n-click"-type operating)....
So, let's be generous and just say that there are some hams with radios that are just used as a "data to HF modulator", and they numbers are ~ 50,000....and those that have complete computer control of their entire HF station, and only use "point-and-click" type of operating, even if they don't have/use an SDR, that's another few thousand, maybe 10,000 - 20,000, but many of these, also bought an IC-7300, 7610, Flex, ANAN, etc....so, the number of those who do the "point and click" operating on a computer, isn't totally cumulative, but rather there is quite a bit of overlap...but..


But, even so, let's just be generous and say the number is 50,000+??



So, at best this makes up a few percent of the total number of hams....certainly less than 5%!! (even if we get real generous and place that number up at ~ 100,000....that's still about 3%!)







5) Now, as for actually operating / making contacts....well, the stats show that "turning a knob" and "talking into a mic" (or tapping a key) are still the predominant ways that hams make most HF contacts....with CW (Morse Code) coming in second place...(although FT-8 is making inroads, especially in the "DX'ing" crowd, where simply "making a contact" is all that counts, not actually talking/communicating/socializing, etc...)



a) The good news is that we can use real (USA/Canada-centric) stats to see some real-world numbers....


The latest numbers I have are from last year's 2019 ARRL Field Day, with approx 36,000 unique stations ...where 46% of contacts were on "phone" (SSB Voice)....42% were on CW (Morse Code)....and the remaining 12% were on other forms of digital comms, such as FT-8 and RTTY...


The exact quote from ARRL:
Quote:
Of the nearly 1.1 million contacts, approximately 46% were made on phone, and 456,000 (42%) of contacts were made on CW. The remaining 138,000+ (12%) of the contacts were made on digital modes, such as FT8 and RTTY.






b) Now, I know that California is different, where FT-8 has made some inroads and in some crowded communities approaches SSB as the most prominent mode of ham HF comms....as well as a large percentage of new hams and/or hams new to HF comms, being pushed into FT-8 largely due to the horrible RFI that surrounds many of them...


But, making a blanket statement implying that most hams don't use the radio like they used to, is rather bold....and wildly inaccurate!



When I read what you wrote: "Very few people use ham radio as in the past, manually turning the dial. These days, it is all digital, all under computer control. The radio is just a data to HF modulator with a keypad to use in emergencies."


I was literally stunned to think that you may actually believe that? Seriously, my first thought was you're just "punking me", looking to see if I'll go off on a rant....but, then I thought maybe he really believes this???




c) Well, I understand that some might not wish to take ARRL stats as an absolute, so I went and called two hams that I've known for 35 - 45 years, and both are VERY active (both operate HF, on-the-air daily, and while neither are "contesters" nor "dx'ers", they both participate in a few contests every year)....one is an avid CW and digital op, and the other is mostly an SSB op with some RTTY....and BOTH came up with the same / similar answers (within a few percentage of each other)....


So, combined with my personal observations, these are the averages of observations from the three of us::


---- A majority of HF ham communication these days is (and has been for decades) via "phone" / "voice" (primarily Single-Side-Band).....of course this varies a bit, year-to-year, and seasonally, but is typically 65% - 70%....


---- The second most common mode of HF ham communication is CW (good 'ole Morse Code telegraphy).....which typically makes up about 20% - 35%...


---- The remaining modes of HF ham comms...."modern digital modes" (FT-8, etc.), FM, SSTV, good 'ole RTTY (FSK), make up about 5% to 10%...


These are supported by both on-air observations of the three of us (of course, not a wide range of statistics) and if you look at recent radiosport contest entries and results, you should see these backed up....
(it takes some time to delve into the details, which I don't have....so, haven't done....but, you'd need to sort through not just the number of entries for cw, phone, rtty, digital contests, but also decipher unique callsigns, to better determine how many stations / operators there are using only one or two of these modes, versus how many are entering all the various modes/weekends, etc...)





d) But, then I thought I'd look at some of the most popular users of FT-8, etc. ("DX'ers"), where the most generous use of the "it is all digital, all under computer control. The radio is just a data to HF modulator" -type of operating will be found....

And, what do you know....FT-8 is a strong contender, and hams using the radio as "just a data to HF modulator" are prevalent....


So, here are the stats....(up 'til 2019....the latest worldwide stats which are available):
Using the DXCC-centric / DX-centric Club Log data, Michael Wells (G7JVR) compiled the data....

Just under 22,000 active ham stations uploaded their logs in an entire year (compared with the ARRL Field Day stats, with 36,000 stations, in one weekend)....
18,000 stations logged SSB Voice contacts
14,200 stations logged FT-8 (or PSK, or other digital modes) contacts
13,900 stations logged CW (Morse Code) contacts


Of course, there were millions of contacts collectively logged by these 22,000 stations, and as you can see from the "mode specific" stats, there is a good deal of overlap...


As the raw data shows that about 82% of stations logged SSB contacts....64% logged FT-8 contacts....and 63% logged CW contacts, which shows these users/stations take advantage of many different modes to "make the contact"....


But, more importantly the data shows that SSB is still a dominant mode in ham radio, even if FT-8 is making inroads, and further while FT-8 contacts (and the new, pared-down FT-4) are just callsigns, location, and signal report, (done in 30 - 45 seconds) and can be accomplished autonomously, it makes sense that their raw total of contacts would be much higher than those of other modes, and they are...


Actual raw FT-8 contact numbers logged/uploaded on-line to club log, do out-number SSB contacts logged/uploaded online.....the raw numbers show FT-8 contacts logged/uploaded to in the 45% - 50% range, with "phone"/SSB contact raw numbers in the 25% range (and CW in the 25% range), for the entire year...and this again is for the DXCC-centric and DX'er-based databases....so, while if all you look at is the number of raw contacts logged/uploaded to DXCC-databases, then yes FT-8 does out-number SSB (and CW)....but, this is a rather cherry-picked way of looking at things, and a rather narrow view of how ham radio / modern ham radio actually works!



Btw, being that all of this log data is done on-line, much of it automatically (all of the FT-8 logging, etc.), and being that the ones using their radio as "just a data to HF modulator" and are more likely to think "These days, it is all digital, all under computer control", are certainly more likely to use on-line logging and upload their contacts into the database (perhaps significantly more likely), in my opinion this is the most generous representation of the "just a data to HF modulator" theory, and as such shows some bias in favor of this theory...

But, let's be generous and just say that their stats are close??


And, as for some other stats from the same source..
DXpeditions use of FT-8...


During the entire year, 97 different Dxpeditions uploaded their logs...64 of them reported using at least some FT-8...
But, the stats on actual contact totals might be surprising?

'Cuz, from all 97 logs (actually just those 64 that reported using FT-8 mode), a total 2.33million contacts were logged, with 150,000 contacts being FT-8...

150,000 out of 2,330,000 is 6.43%....

That might seem surprisingly low....but those are the facts...

{Of course, you can find some other stats on-line to support various theories....but, just remember that those that operate these modes (FT-8, etc.) are much more likely to use online logs (almost always), versus us old-timers.... LOL (heck, I still use a paper logbook....and still have actual paper QSL cards....I know, I know, I'm so "20th Century"...}




6) How do we reconcile these varying stats?

While it's quite easy to see the facts and see how small percentage of ham radios are actually computer-controlled to use "point-n-click" operating from a computer / how small percentage of ham radios are used as just a "data to HF modulator"...


When it comes to actual contacts / communication.....
If we just look at the stats cursorily, the ARRL stats have 60% more stations to compile from, versus the club log data, and being the club log data is DXCC-centric (where a much higher use of FT-8 is known)....and further add in my data from myself and my friends....how do we look at this without bias??

I'm not a "Stats and Probs" guy....and even if I was, some of the data that we have is skewed...so, what to do?


In my opinion, it seems quite clear (from the stats / facts provided here, and my own observations) that most hams actually have radios with knobs!
And, even those with knobs or not, few are using them in "point-n-click" operations....the facts / stats support the opinion that most hams actually do use their radios as radios!!

Most hams do actually use ham radio as in the past, manually turning the dial!!

So, please let's just stop this nonsense and move on....'cuz I'm done!!



Even though FT-8 is highly used for "making a DX contact", its use is still only represented by a fairly small fraction of actual active hams....but...
But, it is equally clear that FT-8 (and other "negative S/N modes") is making inroads and will be used more in the future by more hams as they are further surrounded by more and more RFI sources...


{We sailors have a definite advantage there....we can rid our boats of the RFI producing crap, and enjoy the airways, the way God intended! LOL }








7) As I wrote above, for the life of me, I cannot see how much of this (how many hams use their radios as radios, versus how many use it as a "data to RF modulator") is relevant to my fellow sailors??

(and, I suspect just us discussing this turns some off / away from ham radio....which is very unfortunate!)

As for the HF-DSC non-issue....well, for 99+% of the sailors out there, this is a non-issue....
They either have (or plan to have) a MF/HF-DSC-SSB radio, or they don't (and have decided they don't need one)....
And in my mind, BOTH of those categories / choices are just fine....they make sense to those sailors for their applications!!! (trying to make this controversial, is just a waste of time...'cuz in my mind, it just isn't)




Sorry to be dragged into this non-controversy....but, I just couldn't let a wild ass opinion in regards to ham radio, pass for a fact!!


Fair winds...


John
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Old 12-06-2020, 11:15   #113
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

John,

Thank you for these stats, they do look very convincing. I am just sharing my observations as a sailor and ham, and I am sure they are biased in one way or the other. Hers is what I hear on the radio waves in SoCal:

- Wefax is steady, most of the day. This is a digital mode (analog actually but let’s skip over the details).

- NAVTEX at night and occasional Sitor broadcasts. Again, a digital mode.

- 95% of the calls on the DSC frequencies are test calls. Very few people if any use DSC to “ring” the other station. So, having a DSC radio is nice but not user friendly unless used for emergencies. For regular monitoring of DSC, it is so much nicer to interface with a computer and a DX Atlas. You see all the ships’ positions, etc. It is just more fulfilling this way. For emergencies, as discussed you can use either whatever people feel more comfortable with. But do note that the cost of getting into signaling is much lower if you get any ham radio plus computer vs. the 802.

- Voice nets, mostly 14.300. You get regular contacts but the conversations are totally boring.

- FT8... the waves are littered with FT8 signals. There is always someone trying to make contact. Personally, I am against FT8 for some of the reasons you mentioned but all I hear on the radio waves is FT8. 80% of the time.

- You do hear some Morse code but rarely. If the stats say that it is 4x as much Morse code contacts as other digital modes, so be it but if you listen to the bands, the ratio is something like 10x more FT8 contacts than anything else. I can’t explain the difference, just sharing my observations.

- Then you hear a lot of Pactor, likely driven by sailors retrieving email.

The point here is how to make the hobby more popular and interesting to more people. And I personally believe that we have to embrace digital modes because they are more effective (better signal to noise ratio) and cooler. It is hard to make people use more HF voice than they have used in the past. The propagation is bad and voice quality is low. The forward in my opinion is to popularize digital selective calling. That could very well have been DSC but given the limited selection of radios and the clunky interface it has not happened. ALE is much better but it is difficult to do in software and you need much better radios to do ALE effectively. There is a great initiative called HamRing that is close to completing an app that has ALE and SelCall messaging. It is very cool (I am an Alpha tester), you can ring people, write short messages to them and if need be call them on a voice channel. I have been trying to convince the developer to add DSC support as well and he may do it one day. The thing here is that this is the future. We want to make HF as easy to use as texting on the phone. For this you need calling frequencies, automatic link establishment, etc. This is impossible to do within the Icom marine radios, you still need a computer interface. Hence this entire discussion. If the marine community does not want to pick this up and wants to be stuck in the old world of voice nets and emergency only DSC, let it be so. But the future of ham radio is HamRing and similar apps and it is all digital. We need to embrace the way radio use is changing vs. insisting that we should only use what we are familiar with.

This is all I am saying not anything more or less.

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Old 15-06-2020, 08:35   #114
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Hello to all,

1) I'd like to reiterate some helpful, but brief (?), comments here...

(Forgive my bluntness here....and, please understand I mean no offense to any of my fellow sailors, just desire to help...)



I'm going to try to be brief, especially because I don't want to overwhelm many of you with a detailed treatise on RFI and HF comms.....but, the facts here are difficult to explain in laypersons terms, so it might take a while....


And, while I have continued to emphasize something that is all too often ignored (even by so-called electronics "experts"), I'd like to thank Pizzazz for further highlighting this as an issue that is vitally important to HF comms success these days...noise / RFI / "can't-hear-itis"...


Quote:
Originally Posted by Pizzazz View Post
I am just sharing my observations as a sailor and ham, and I am sure they are biased in one way or the other. Hers is what I hear on the radio waves in SoCal:

- Wefax is steady, most of the day.

- NAVTEX at night and occasional Sitor broadcasts.

- 95% of the calls on the DSC frequencies are test calls. Very few people if any use DSC to “ring” the other station.

- Voice nets, mostly 14.300.

- FT8... the waves are littered with FT8 signals. There is always someone trying to make contact. Personally, I am against FT8 for some of the reasons you mentioned but all I hear on the radio waves is FT8. 80% of the time.

- You do hear some Morse code but rarely. If the stats say that it is 4x as much Morse code contacts as other digital modes, so be it but if you listen to the bands, the ratio is something like 10x more FT8 contacts than anything else. I can’t explain the difference, just sharing my observations.

- Then you hear a lot of Pactor, likely driven by sailors retrieving email.


The above observations / what you're hearing, or better yet what you're not hearing, are very telling... And, I can explain the differences....



If someone is listening / trying to make contact from land / on-shore, and/or in a marina (especially in a marina in an urban or densely-populated area), their ambient receive noise levels are usually quite high....while in the past (as little as 10 - 20 years ago) we used to say industrial areas had the highest ambient RF noise levels, followed by dense urban areas....now-a-days, dense suburban areas are generally the worst, followed closely by dense urban areas and typically industrial areas...(although there are variations / exceptions, and some of these can swap positions.)

[Please note that these high ambient HF noise levels in some of these locales can be as much as 20 - 30db higher than when at sea / in remote areas....(that's 4 to 5 "S-units" higher noise levels)....and sometimes can even be higher!!]

This means those attempting to use HF radio in these dense suburban, and dense urban areas (and/or from a marina / yacht club / boat yard), have quite a challenge these days...as in addition to the higher ambient RF noise levels, many have limited space for antennas and/or limited abilities to raise an antenna up above the ground by sufficient amount to mitigate much of the RFI from their own dwelling (and/or neighbor's)...and some times they are are even forced to use a vertical antenna (which, in addition to having significant gain disadvantage, versus even a 1/2-wave dipole....with most man-made-noise being vertically polarized, it also suffers from significant increase in noise response)...



Some important facts here (using the things that Pizzazz mentioned):

- The USCG HF WeFax and HF SITOR broadcasts (as well as their HF-SSB Voice broadcasts) are transmitted with wideband, moderate-to-low gain antennas, but with 4000 watts of power...(that's 14db to 16db stronger power than most pleasure boat marine HF / "SSB" radios and/or HF ham radios) And, these are very strong and should be easily received, even in high-noise areas...

- The 518khz USCG NAVTEX, is transmitted with 2500 watts or power...here again these signals are very strong, day and night, and are designed to be easily received by even small antennas at distances of 200 to 300nm...(note that the USCG is modeling ranges attained using lower transmit powers, and some USCG NAVTEX stations may have reduced transmit power in coming years, but should still maintain their IMO/GMDSS-required range)

- DSC calls from SOLAS vessels are generally from their GMDSS consoles with 250 watts of transmitter power....(there are a few with 500 watts, but most are 250 watts) and from ship-borne antennas.....[see how effective / efficient our antennas mounted over sea water, are?] while this is only a couple db more than our pleasure boat radios, you see how important antenna system efficiency is??



- Ham stations:
Although, a majority of ham stations use only 100 watts of power, most using SSB and CW will have decent antennas (even a 1/2-wave dipole, a half-wave high, is damn good antenna, compared to a vertical on-land)...and many will also have a directional / gain antenna for the higher bands, such as 20 meters (14mhz) and above...

Many of the stations / net control stations you hear on 14.300 are using decent gain antennas (many with yagis on towers), and many use 1000 - 1500 watts of power....

Because of the significant signal-to-noise advantage of CW (Morse code) bandwidths over SSB, many ham CW ops don't use much transmitter power....except for during CW contests and serious CW dx'ing, most ham CW ops use 100 watts or less....

While those using FT-8 for DX'ing, etc. are using all the power their stations can muster while still keeping their signal clean / linear, most using FT-8 are not using high power....most are using 100 watts or less....many use as little as 20 to 30 watts, due to the poor linearity of most ham transceivers at 100 watts, as well as the duty-cycle challenges of FT-8 causing adverse heating, etc...





2) Most pleasure boat HF stations have (or rather, should have) very low ambient RF noise levels....once you're more than a 1/2 mile from much of the civilization, you're likely in "rural" to "quiet rural" levels, and once more than a few miles away, your noise levels are typically even lower/better than "quiet rural"....of course, that doesn't include what RFI you're generating on-board!



Have a look here, for some comparisons of man-made noise in various locales...




(please note that the red "s-meter" numbers on the far left, are unfortunately inaccurately graphed once you get to S-3 and below....see by numbers below)



FYI, I don't want to get into a debate here about "S-meters" and their accuracy (or lack thereof, in most modern ham radios....even poor accuracy / poor linearity in some modern SDR's, which is heartbreaking 'cuz you'd think these guys would pay attention, but oh well)....but, I would like to correlate these numbers with what you should see....

Modern HF receivers noise floor / minimum discernible signal = ~ -132 to -139dbm (although typically not a determining factor, as long as it is lower than -120dbm)....and typical signal level to produce a 10db signal to noise ratio (internal receiver noise, not external noise) is -122 to -129dbm (and again, since the 1960's, this is usually a rather moot spec, as all decent HF receivers have sufficient sensitivity, low enough noise floor....so, for the 99.999% of situations, you can ignore this spec altogether!)

S-meter readings, as designated by Collins Radio in the 1950's, and accepted worldwide (ITU, IEEE, etc.) as a standard since then...
S-0 ~ -127dbm (a very weak signal, but usually usable/readable)
S-1 ~ -121dbm (a weak, but usable signal)
S-2 ~ -115dbm (a weak, but very usable signal)
S-3 ~ -109dbm
S-4 ~ -103dbm
S-5 ~ -97dbm
S-6 ~ -91dbm
S-7 ~ -85dbm
S-8 ~ -79dbm
S-9 ~ -73dbm (a very strong signal)
S-9+20 ~ -53dbm (an extremely strong signal)
S-9+40 ~ -33dbm (an extremely strong signal, that most ham radios have trouble with)



As you see in the chart even in a low-density suburban / rural setting (where these real-world readings were taken and placed on the chart with red dots and blue bars), it's almost impossible to have "quiet rural" ambient noise levels (that we on boats away from shore enjoy...easy-peasy)...


BTW, in the world of HF radio, our noises are exclusively of two varieties....and here are some detailed, but layperson-targeted, explanations / descriptions....

-- natural / atmospheric noise (from natural atmospheric electrical activity / lightning)....

-- man-made noise (RFI, or Radio Frequency Interference)....


{galactic noise, below 25-30mhz, is always below the natural atmospheric noise, and the only time solar-noise in the HF spectrum would ever be noticed is when a geomagnetic storm (in our atmosphere) is mistaken for solar-noise because it is caused by our sun, so some will call it sun-noise, but at HF this is below our atmospheric noise....and geomagnetic storms, take place in our atmosphere... }

--- Let's first look at daytime natural / atmospheric noise:

- At frequencies of 7mhz to 8mhz, and below, daytime natural / atmospheric noise is always well below the level of "quiet rural" man-made noise (which is typically S-1 to S-2 on 8mhz down to 3.5mhz), typically 10db+ below...and sometimes as much as 20+db below....so, daytime use of 80m and 40m ham bands....and daytime use of 4mhz, 6mhz, and 8mhz marine bands, is highly dependent on your transmitting antenna system efficiency / effectiveness AND your reduction of on-board RFI!

- At frequencies from 10mhz thru 20mhz (generally because of the distances these noises travel), daytime natural / atmospheric noise can sometimes be higher than "quiet rural" (S-1 or lower, at 14mhz is typical), and I generally see this as a "higher ambient noise level" when I'm on 20m ham or 12mhz marine....here antenna efficiency and effectiveness is also important, but surprisingly we can accept some low-level / sporadic on-board RFI...

- At the higher end of the HF spectrum, above 25mhz, daytime atmospheric noise is again similar to the lower freqs and is usually below the "quiet rural" (S-0, at the upper end of the HF spectrum) man-made-noise levels...and when these frequencies are "open"/usable, signals are usually strong, so while reducing RFI is important here, we can sometimes accept/tolerate some low-level / sporadic RFI...


--- Nighttime natural / atmospheric noise:

- Below 10mhz, typically at or below normal "rural" (S-4 to S-5, from 8mhz down to 3.5mhz) man-made noise levels....but nighttime radio signals at the lower frequencies are generally strong, so an increase in natural noise is usually not an issue...and here at nighttime on the lower frequencies, some on-board RFI is accepted....{hence why much use of Sailmail and PACTOR below 10mhz is early morning or at night}

- In the middle of the HF spectrum, nighttime natural noise is usually at or near the "quiet rural" (S-1 or below, is typical at 14mhz) man-made noise levels...here, like daytime low frequencies, eliminating RFI is very important!! As well as your antenna system effectiveness / efficiency....

- The upper end of the HF spectrum, nighttime natural / atmospheric noise is usually at or below "quiet rural" (S-0 or so, is typical at the upper end of the HF spectrum) man-made noise.....but now-a-days, these frequencies aren't typically usable at nighttime much....but should be by 2023 thru 2027....so, be prepared by reducing/eliminating on-board RFI...


So...
So, if your noise levels are higher than these specified here, you're receiving man-made noise (RFI)!! And, you should investigate where this is coming from and eliminate / reduce it (entire books are written about this subject, so I will not attempt to write about here)....


Now, what about those on-board, with our typical marine HF radios? How do we determine what level noise we have?

The good news is that those with modern Icom marine HF radios (M-803, M-802, M-710, M-700pro) you have a relative signal strength meter, with 8 segments of LCD illumination possible....now, this is not an accurate way of measuring things, but it's not too bad, and certainly better than nothing at all...


All the above are facts, and established specs....but here is where opinion and personal experience come in....

Using the Icom marine radio "S-meter":
--- one segment illuminated is about S-2 (approx S-1 to S-2)
--- two segments illuminated is about S-4 (approx S-3 to S-4)
--- three segments illuminated is about S-5

Again, this is not an accurate way of measuring noise....but, it is what we have....

So...
So, on frequencies below 15mhz, if you have more than one segment illuminated during the daytime (and, any segments illuminated, if above 15mhz), then you are receiving RFI!

Be aware that some of this can be from nearby shore / other boats, not always on your own boat...(this is what I have at my dock, where I regularly have one segment illuminated on 8mhz, occasionally even at 12mhz and 14mhz, and typically one to two segments illuminated on 4mhz thru 7mhz/8mhz, and this is all RFI from shore, from houses, from neighbor's boats, etc....)


And, at nighttime, of course natural / atmospheric noise on the lower frequencies (8mhz and below) will be higher, so if you see two segments illuminated (but none, or only one, during daytime), this is probably natural / atmospheric noise (nothing you can do about that)....note that you can have more segments than that illuminated, especially during summertime, from natural / atmospheric noise, and again nothing to be done about that, except improve transmit antennas and/or use a different band...

From 10mhz thru 15mhz, nighttime, you can have one segment illuminated, but usually none....and at the higher HF frequencies, at nighttime, you should see no segments illuminated..



3) As many of you know I started playing with electronics and "radio" as a kid in the 1960's....what some don't know is that it took a few years (until I was a young teenager, in the 1970's) before I realized the basics of successful HF communications was all about receive S/N, not about more signal!

Of course, back in those days (before the personal computer, way before cheap switch-mode power supplies, and way way before the plethora of made-in-China electronic / microprocessor-driven devices / consumer electronics / lots of crappy switch-mode supplies).....so, back in those ancient times of the 20th Century, maximizing receive S/N was all about: radiowave propagation, antennas and operator skill/expertise....

These days, it has a lot to do with antennas and RFI, as well as understanding of radiowave propagation and operator skill...

Yeah, it seems like a no-brainer now....but back then 50 years ago, to me as a kid, it was a major revelation...



4) When laypersons hear that HF comms is all about receive S/N, many of their eyes glaze over....and most are concerned about looking ignorant, so they just nod / smile, but in reality they walk away with little understanding of this....

When I try harder to impress upon them that this (receive S/N) actually is what it is all about, and that it means:
a) "RFI",
a) "understanding radiowave propagation",
b) "antennas",
c) "overall operator skill / expertise",

[yes, there are two "a" categories here...'cuz these days, on-board our boats, they are tied in order of importance]

Many will just ignore these criteria, and/or assume they can solve these issues with a smartphone App (which they cannot)....and by the time they realize they've spent money on something that they do not know much about, nor hardly anything about how it works.....they either:


a) just forget about the whole project, chalking up the $$$ invested to a "bad decision" or "costly experience"....(and then many say "this crap doesn't work....just buy a satphone")


b) look for alternatives....(in addition to satphones for sailors)

---- Alternatives in the world of personal/consumer ham HF comms (primarily on-shore): PSK 31, and especially FT-8 (and other negative S/N modes) have flourished due to both the increase in RFI and the decrease in the ability to use optimal antenna systems (as well as an unfortunate significant reduction in radiowave propagation understanding / reduction in overall operator skill)

---- Alternatives in the world of personal/consumer maritime HF comms (on-board pleasure boats): PACTOR III and IV (and using a computer-predictive-propagation chart, and computer control of the radio) have also flourished....and here while we do have the ability to rid our boats of RFI-producing devices (or at least reduce/mitigate RFI so that it doesn't adversely effect of HF comms), many sailors are unfortunately ignorant of the importance of this, as well as having little personal knowledge of radiowave propagation and little real-world experience using HF radios...


{now, as I've written earlier (many times) we on mid-sized sailboats cannot improve much upon a long backstay antenna and direct-sea-water-connection for antenna ground....and, of course, we don't have the room for separate / optimized receive antennas, so the discussion here about boats / marine installations, just tries to impress the "antenna" and "antenna ground" situation as a no-brainer....(and those without backstays, multihulls, etc., can use an insulated shroud or stern-mounted whip....but still utilize a direct-sea-water-connection antenna ground)....just please understand that when on-shore, or in situations where different antennas (i.e. horizontal antennas on land, directional antennas, antennas secured well away from RFI sources, etc. etc. etc...) can be used, then "antennas" returns as to position "a", in order of importance!! And, certainly a vertical on a ground mount, or on a pole/mast, or some of the ridiculous "snake oil" antennas sold to the uninformed, are the worst choices for HF antennas on land!!! }


In our modern 21st Century lives on-shore, "RFI" (Radio Frequency Interference) has become such an important factor it now equals the other three! And, in many (at least some) modern residential, urban, and suburban areas, "RFI" mitigation can even be a higher priority....although the other 3 criteria are still VERY important and cannot be ignored at all, many times now "RFI" is THE make-or-break criteria!!


So, when Pizzazz, and others, comment about what they hear (not too much in many cases), and when others say how "noisy" things are, and/or some comment that "propagation is horrible", etc. etc....many times (most times) this isn't due to poor propagation at all, nor usually due to signals being too weak (although some cruising boats are much weaker than others and vice-versa, and therefore shows the variations of how well and how poor an HF system on-board can be installed)....
It is almost universally due to these factors:
a) poor understanding of radiowave propagation
b) too much RFI nearby
c) poor antenna system design / installation (of both the other boat your listening to, and your own)


I know these statements I'm making here might seem rude, and might sound like I'm "blaming the victim" for having so much RFI around them and not having enough understanding of radiowave propagation....but, please know that these are unfortunate facts....and this is not the fault of those trying to use HF radio comms, but rather the fault of those selling/marketing these systems (and those profiting from these users, such as SCS, etc.), for not better informing their customers of these facts!


FYI, I gave my first talk / seminar on antennas and propagation, when I was a teenager in the 1970's and nobody took me seriously (heck, the old timers actually laughed at me when I tried to teach them that their antennas do not dictate the angle that their signals are reflected / propagated at, but rather it's the ionosphere that controls this).....and in later years, I've tried to highlight the importance of choosing an antenna (primarily transmit antenna) whose pattern produces adequate gain at the angles desired, rather than just looking for one that has the most gain....and selecting receive antennas that maximize rec S/N, not ones that produce the highest signals!!

Unfortunately, in my experience even in today's world of knowledge-at-your-fingertips, most ham operators don't grasp these facts!!





5) Propagation / Solar Activity....If you hear someone bemoaning how bad propagation is, take a minute and think (and look at these charts) and ask yourself how did this "HF radio stuff" work years ago when solar activity was low??

The answer is, it did work...and it did work very well!!

Oh, and to be clear....low solar activity does NOT mean poor HF propagation (despite what so many HF radio users falsely assume!)......but it does mean the high-end of the HF spectrum (> 20mhz) can suffer poor (or little) propagation....and this simply means that you need to move to lower frequencies (where RFI can typically be worse, many times a lot worse) in order to optimally use the airwaves!!


Please let me repeat this....low solar activity does NOT mean poor HF propagation, but it does mean the high-end of the HF spectrum (> 20mhz) propagation can suffer or be non-existent, and this means that you need to move to lower frequencies (where RFI is typically worse, many times now-a-days RFI is a lot worse at lower HF freqs) in order to optimally use the airwaves!!

And, here you now see where knowledge of radiowave propagation, and RFI, come into play!!



Way back when, we had folks teaching, and folks learning, about radiowave propagation....we had folks that understood (or were taught/learned) that optimizing their antenna systems was important.....we had folks mitigating the RFI issues they had....


But, what we didn't have the last time the solar activity was low, was so much RFI producing devices (sure in 2007 - 2009, we did have a lot of cheap made-in-China crap, but not as much as we do now....and unfortunately many sailors also unknowingly haul some of this stuff on-board as well!)....but, as I write above, we did have radio ops that mostly understood how to recognize what noises sound like, and how-to optimize their systems (reducing RFI, improving antennas, better understanding of radiowave propagation, etc.)



Have a look at these charts of solar activity...and you'll see what I mean!









BTW, I have a video showing quick and easy HF comms from last year (2019), when we were just about at the bottom of the solar cycle....in terms of production-values, it's the worst video I've ever made, but it does show you how easy-peasy it is to make quick HF contacts, even from the dock, during the bottom of the solar cycle...so please have a look and you can see for yourself....



FYI, in addition to the video (linked below), here is some real-world use / results of mine, from the previous solar minimum...

During our last null in solar activity, 2007 - 2008, I sailed across the Atlantic (twice)....and during both crossings, I had very good to excellent HF comms....
And, yes while the USCG and UK Met office HF WeFax broadcasts (as well as USCG SSB Voice broadcasts, and those of WLO/Shipcom Radio), were all loud-n-clear all the way from South Florida to Europe....

The low-power maritime HF comms (and HF ham comms) were also excellent and loud-n-clear!!

In addition to communicating with Herb on 12.359 daily on passage, I made contact with Herb while in port in Gibraltar, tied to the dock at Marina Bay marina in Gibraltar...yep, even with all the shore-side / marina RFI (which was quite frustrating), I made contact with Herb and discussed weather, etc...

{fyi, Herb just had 150 watts from an Icom M-710, to either an AT-130-fed vertical w/ a few radials or his primary 12mhz antenna (a loaded 12mhz, 2-element yagi at only 30' above ground)...and this is all from his suburban land-locked location in Hamilton, Ontario (near Toronto)....}


I also regularly checked into other HF nets (talking to other boats at sea, and to those already in the Med or in Caribbean)...all low-powered radios like my M-802.....also checked in with the MMSN on 14.300, daily....and almost every evening speaking with some friends back in Florida on either 75m (where sometimes the static crashes from evening T-storms covered up their 100 watt signals, so they'd run 1000 watts sometimes on 75m)....or on 40m (where they were using 100 watts)....and sometimes speaking with them during the day on 20m, where they were also only using 100 watts....


Further, I regularly "spun the dial" while on watch in the cockpit, as I have remote mic and headphones to use in cockpit, and the M-802's microphone up/down buttons allows for "spinning the VFO" to find someone interesting to talk to, and I'd always find dozens of hams willing to talk about sailing, etc....and never had any problems with them hearing me, nor me hearing them....usually all "loud-n-clear"!!



I generally did my weather (WeFax) reception in mornings (and evenings if needed), checked-in with the MMSN in early afternoon, spoke with Herb in late afternoon/early evening, and my casual ham comms on night watch, but sometimes I'd yack away at any particular time....so, I had reliable 24/7 HF comms, used morning, afternoon, and at night!!


I mention all of this, to highlight that all of this operating was at the bottom of the solar cycle (like we have been in this past 2 years)!!

All of it SSB voice!!

And, all of it perfectly clear!!

Much of this is communications covering thousands of miles, with only 100 - 150 watt radios!


(During these passages, at the minimum of solar activity in 2007/2008, I think the shortest HF comms path was about 400 - 500 miles, the longest regular comms path was 4000 - 5000 miles, with a few QSO's to some VK's > 8000-9000 miles away...)


These facts are important here, as they show:
a) Low solar activity does not mean poor propagation!
b) HF SSB Comms (both ham and maritime) can be easily done with 100 - 150 watts of transmitter power, even at times of low solar activity!
c) Attention to antenna system design/installation....optimizing antenna systems/antenna ground systems....are important!
d) eliminating / mitigating RFI is very important to successful HF comms these days!



Just thinking about our "normal noise levels" on-shore or at the dock (or within 1/4 to 1/2 mile of civilization) these days, in comparison to how things were 20+ years ago...shows us two things:

--- how good we sailors have it on-the-water....
--- and how bad things are for those living in apartments/condos/zero-lot-line homes (heck even those in single-family homes, in many suburban areas, are highly impacted by RFI...)



And, this is why having an antenna up and away from these RFI sources is such an advantage....
Heck, on-land, depending on the band and the path distance, even a dipole at 50' on the HF bands, is going to out-perform the best vertical by 10-20db on transmit and probably 20-25 db on receive S/N (sometimes even 30db better receive S/N, than a vertical in the back yard)....and even a small yagi at 50' (or more) can be 20-30db better on transmit than a vertical in the yard!!
(opps, I could go on and on, but this is drifting way too far afield of our boats and our boat communications system....sorry!)


Now, the good news is....on-board our boats (except for shore-power/AC-generator-driven battery-chargers, and some of our refrigeration units) we have few actual marine systems that produce RFI....
But, many do have more than a few consumer devices that do produce lots of RFI (wall-warts and other switch-mode power supplies / chargers are the most prevalent offenders....but, if you read thru this thread and/or do a search for the term RFI and my user name, you'll see quite detailed list and discussion on this...)




Okay, I think you all get the gist now....RFI is bad....(hmm, could I have just written those 3 words up front, and saved myself hours of composing???)


fair winds.

John


Here is the crappy video (poor camera and poor production) but good info, that shows how easy-peasy it is to use HF radio, even at the bottom of the solar cycle!
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Old 28-07-2020, 11:21   #115
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Re: Marine SSB Stuff (how-to better use / properly-install SSB, & troubleshoot RFI, e

Hello to all,

Once again I'd like to add some clarifying information.



Due to my efforts to promote HF-DSC, I unfortunately went too far and inadvertently caused some confusion....please ignore and forget my comments specifically dealing with "routine" HF-DSC signaling (you can skip that video, as well), unless you have some unique/specific need to investigate / learn about "routine" signaling....

Please just stick with the "Distress" (MayDay) signaling and "Safety" (Securite`) signaling (for weather, navigation, communications testing).



Those of us on private yachts, with the Icom M-802, etc., will mostly be using MF/HF-DSC for "Distress" signaling (MayDay) or "Safety" signaling (for weather, navigation / communications testing, etc.)....and that's probably it...


And, you're going to be using one of the six Int'l GMDSS DSC "Safety" / "Calling" frequencies [2187.5khz; 4207.5khz; 6312.0khz; 8414.5khz; 12577.0khz; 16804.5khz]



Although, I already mentioned that the USCG offers "automated DSC Testing" on 4207.5khz, from 3 of their locations, if you are beyond 4mhz comms range, they do accept DSC "Safety" calls for testing / verifying proper HF-DSC system operation, as long as you don't do this often (typically once per year / once per season, or only prior to an ocean passage).



Some additional supporting info for this:
From US FCC Part 80 Rules & Regs (Maritime Mobile Service):

80.359 Frequencies for digital selective calling (DSC).

(b) Distress and safety calling. The frequencies 2187.5 kHz, 4207.5 kHz, 6312.0 kHz, 8414.5 kHz, 12577.0 kHz, 16804.5 kHz and 156.525 MHz may be used for DSC by coast and ship stations on a simplex basis for distress and safety purposes, and may also be used for routine ship-to-ship communications provided that priority is accorded to distress and safety communications. The provisions and procedures for distress and safety calling are contained in ITU-R M.541-9 (incorporated by reference, see § 80.7), and § 80.103(c).



And, some further info (primarily dealing with the equipment and crew familiarity):

Quote from US Gov't Pub 117:


Use of GMDSS Equipment for Routine Telecommunications; GMDSS telecommunications equipment should not be reserved for emergency use only. The IMO has issued COMSAR/Circ.17 (dated 9 March 1998) which recommends and encourages mariners to use that equipment for routine as well as safety telecommunications. The following recommendation is extracted from Circ.17:

Use of GMDSS equipment for transmission of general radiocommunications is one of the functional requirements specified in SOLAS chapter IV, regulation 4.


Regular use of GMDSS equipment helps to develop operator competency and ensure equipment availability. If ships use other radio communication systems for the bulk of their business communications, they should adopt a regular program of sending selected traffic or test messages via GMDSS equipment to ensure operator competency and equipment availability and to help reduce the incidence of false alerts.

This policy extends to all GMDSS equipment suites including Digital Selective Calling (DSC) on VHF, MF and HF, to the Inmarsat systems, and to any duplicated VHF and long-range communications facilities.



{Over the years, I've attempted to be a bit less USA-centric, trying to point to the international uses of the GMDSS.....and I've mentioned some sailors recommendations for using MF/HF-DSC in ocean rallies, etc., as well as encouraging the use of "regional MMSI's" for regional-group calling... but these are rather specialized / niche uses, and I now realize that those interested in them will either already be aware or will be smart enough to ask/learn....so, no need for me to be rambling on about them... }



Without going into the weeds of the original GMDSS plan, nor specifically Digital Selective Calling (DSC), please remember that this system was originally designed/planned in the late 1980's / early 1990's, and implemented starting in 1992....so, much has changed....not the least of which most "public correspondence" (ship-to-shore phone calls) is handled via sat comm, as are most "data comms" that aren't being handled privately via PACTOR....


While the MF/HF-DSC system (as well as the VHF-DSC system) is an integral part of the GMDSS (Global Maritime Distress and Safety System), the main use these days is the "Distress" signaling and "Safety" signaling, not the "Routine" signaling that was intended to be used for both ship-to-shore and shore-to-ship signaling, by both "public coast stations" (for "public correspondence" and ship's/fleet's business) and "private coast stations" (usually for ship's/fleet's business, using SITOR/FSK)...


So, while we can continue to rely on the GMDSS to be there when we need it [406mhz EPIRB's; NAVTEX; VHF-DSC-FM; MF/HF-DSC-SSB; SafetyNET broadcasts; INMARSAT-C (and now / soon-to-be INMARSAT FB and Iridium Certus); SART's (AIS-SART's or SART-X's)], we should remember (or rather I should accept?) that most sailors/cruisers (except those using NAVTEX...mostly in Europe or Asia), these days only use the GMDSS in times of "Distress"....so...


So, perhaps we could learn something from the IMO (International Maritime Organization) that started the whole SOLAS (Safety-Of-Life-At-Sea) idea, and came up with the GMDSS in the first place?



Maybe we should heed their advice?



Have a look again at what their advice / recommendations are:
Use of GMDSS equipment for transmission of general radiocommunications is one of the functional requirements specified in SOLAS chapter IV, regulation 4.


Regular use of GMDSS equipment helps to develop operator competency and ensure equipment availability. If ships use other radio communication systems for the bulk of their business communications, they should adopt a regular program of sending selected traffic or test messages via GMDSS equipment to ensure operator competency and equipment availability and to help reduce the incidence of false alerts.

This policy extends to all GMDSS equipment suites including Digital Selective Calling (DSC) on VHF, MF and HF, to the Inmarsat systems, and to any duplicated VHF and long-range communications facilities.



Perhaps this is simply what I should have recommended from the beginning, some ~ 17 years ago, when I first started touting "HF-DSC"? But, whatever the case, that's what I recommending today!


I do hope this info is helpful to you all.

Fair winds.

John


P.S. Don't forget the other "sticky" here, on Maritime HF Comms

HF-SSB Radio, Proper Installation Tips/Techniques, etc.

https://www.cruisersforum.com/forums...tc-198305.html


And, for those looking for the easy-peasy link to a free video series / Playlists, have a look here:


HF-DSC Comms

https://www.youtube.com/playlist?list=PLnN6ygtZ3h2n3z5nlv-ga2zYuPozhUXZX


VHF-DSC Comms

https://www.youtube.com/playlist?list=PLnN6ygtZ3h2m-IejYg7J6QugtO2epizxF


Generic Maritime HF comms
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y


Offshore Weather
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2mPZAx2vWzdjTJjHlChruyY


Icom M-802 Instruction Videos
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2npivDjoFrC-8QKVyMb4tVr


Offshore Sailing
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nbwAGh5DKgTCj15iyl6qoY
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