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Old 08-09-2018, 22:12   #76
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Thank you, John. I will try New Orleans and Baltimore.
I am having some great success receiving far away stations for voice - like Havana - just from the mini antenna.
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Old 09-09-2018, 06:54   #77
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Symphony,
I never mentioned "Baltimore", and as far as I know there are no HF broadcasts (of any type) from Baltimore...

Please read what I wrote earlier, AND more importantly please take the time to learn about HF Radiowave Propagation, and how to use HF communications....just like you do/did to learn navigation, sail trim, anchoring, head repair, diesel maintenance, etc. etc. etc....
And, this means always perfecting you HF Voice Communications techniques first...and only then move on to HF WeFax, digital modes!!
(please forgive me for not specifically mentioning this earlier....but, since you mentioned receiving NMN well, I incorrectly assumed you had perfected this... )

Quote:
Originally Posted by Symphony View Post
Thank you, John. I will try New Orleans and Baltimore.
I am having some great success receiving far away stations for voice - like Havana - just from the mini antenna.
I feel that many people these days simply think that "electronics" (smartphones, computers, the internet, etc.) are some how "magic", and assume that they'd never understand how they work so never attempt to learn??
Many just download an Ap, and swipe away??
Use of HF Radio Communications is not like this, no matter what the guys selling all the various radios, software, and gadgets involved, will tell you!
It just isn't!!!!

Unfortunately for my fellow sailors, HF radio communications is actually more like navigation or sail trim, as there are facts that need to be learned AND techniques that you should learn to be a better sailor/navigator, but if you don't know the basics (the facts), then you will never be able to sail or navigate!!
And, if you don't know the basics of HF radio comms, you'll never get it either...sorry to sound so strident, but I've saying this for decades and decades... And, no amount of modern technology has changes basic physics....radiowaves travel the same way today that they did in the 1970's...

Please know this is nothing personal, and understand that I'm NOT saying that if you haven't been doing this for decades and decades you'll know nothing....no not at all!!
To the contrary, for many years I've been adamant that all it takes is a couple hours of someone's time!!
An hour or two of reading and/or an hour or two of watching Youtube videos....all while in front of your radio...and you'll be good to go!

None of this costs you any money!! You don't have to buy anything!!
You don't need to pay for any seminar nor "webinar", nor pay any fee, nor join any club nor organization....nope...
You don't have to pass a test (actually I know many of my fellow licensed ham operators that are fairly ignorant of Radiowave Propagation, so passing a test and having a "license" is no indication of actual understanding of these topics)....

Rather what I recommend is just what I've been saying for many years....read a few books (The ARRL Handbook, etc.) and even the radios' manuals, and watch some videos...all while right there in front of your radio...
{think about how hard learning anchoring or sail trim would be from a seminar....but some groups will tell you that they can do that for HF radios?? really?? well maybe it's possible?? but it is much easier, and much less stressful for the sailor learning, if they do it right there in front of their radio...live...and that's why I did the videos that way...they are LIVE, on-the-air, in the real world, on a real offshore cruising boat, as it is happening, with little editing, no script, no "director", just my extemporaneous narration (sometimes a bit repetitious, but useful)..}

Do it on your OWN time, when YOU can spend an hour or so doing it....NOT when some other sailor offers to show you "how it's done"....
Then do it a second time with the whole crew (everyone can do it on their own, if you all cannot find the time to do it all together)....

Use the videos...watch 'em when YOU have the time....and if that means watching 'em over the course of a few days or a week, first...and then watching 'em on-board in front of the radio, that is good too...{And, sometimes that can be better...because some computers (usually just the power supply) can produce a lot of RFI (radio noise) and can make watching the videos while trying to use the radio frustrating! }
Remember, as long as they are for your own personal use, you can download them from Youtube, store on your computer and watch 'em anytime, even when out at sea away from the internet!!


Watch the videos in the playlists in order, so that they all make sense!
{I understand that you have a different radio than what is shown in the videos, but please understand the radiowaves travel the same way no matter what radio you are using. So....so, please watch the videos, in order...}

Symphony, you will find some of the videos to be moot for your specific application (as they apply specifically to an Icom M-802, and/or are about you transmitting), but....
But, understand that if you watch 'em, you will learn better how the radiowaves travel, how HF radio communications actually work...

Maritime HF Communications
https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y


Offshore Weather
https://www.youtube.com/playlist?lis...zdjTJjHlChruyY


HF-DSC
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX



If you don't have much time to learn all, there is little more I can do to help....but, please at the very least watch the first two videos in this playlist!! Please...
Maritime HF Communications
https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y
But, I REALLY recommend watching all the videos in all the playlists and reading some books...


Quote:
Originally Posted by ka4wja View Post
Symphony,
Sorry, I didn't see your question...as this thread is mostly a "reference" thread, and not one where specific problems are posted / discussed...

Originally Posted by Symphony
question please.

Quote:
I just recd a Tecsun PL880 as a gift. Nice!
I looked up the NOAA voice and immediately tuned into Chesapeake NMN on 6501kHz USB using only the mini antenna. Loud and Clear. An amazing radio as I am in New Haven, CT.

Now I want to try and link to the Black Cat HF Fax app on my iPad. Found the Boston freqs, and subtracted 1.9 from each to find the carrier for my Tecsun.
4233.1 kHz - 6338.6 kHz - 9108.1 kHz - 12748.1 kHz using USB

I scan the 4 channels off and on, with and without long wire, but find nothing but noise today. What am I doing wrong?

(PS thanks to ka4wja for all the posts the past years)


It would be much better if you posted this question in a new thread....
But, since I'm here....

In general, you have two issues...
a) Your distance to NMF, Boston, is quite close....which means their usual daytime freqs (6mhz, 9mhz, and 12mhz) will usually be "skipping" over your close location....(although, 6mhz might work....9mhz and 12mhz will not)
And, you didn't mention what times, time-of-day, you're listening??
Please make sure you know what their transmission schedule is...and note there is a schedule change coming in 2 weeks..

Radiofax Charts - Boston

Also, you may want to have a listen to NMG, New Orleans...
Radiofax Charts - New Orleans


b) You most probably have some (substantial?) on-board RFI (and/or shoreside RFI) reducing your radio's S/N (signal-to-noise ratio)....

You will see a lot of info and links in this thread regarding RFI and RFI mitigation...as well as in the other important thread here:
"HF-SSB Radio, Proper Installation Tips/Techniques, etc."
http://www.cruisersforum.com/forums/f13/hf-ssb-radio-proper-installation-tips-techniques-etc-198305.html


Hope this helps.

Fair winds.

John

I do hope this helps...
fair winds.

John
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Old 27-10-2018, 15:26   #78
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

In another "radio" thread I was giving some detailed info, but some of the acronyms and abbreviations, etc. were a little confusing to some...

Further, it dawned on me that maybe some here reading this sticky could use some help deciphering things?

So...

So, here is what I wrote on the other thread:

Clamdigger, et al,
I gotta' smile here..
Because Clamdigger did make a nice subtle point....I sort of got off into the weeds a bit, huh?
Quote:
Originally Posted by Clamdigger View Post
For those of you who read this thread and thought, 'what the heck are these guys discussing?' Do yourself a favor and check out sea-tech.com and Richard will gladly answer your electronic questions! I inquired and found him to be extremely helpful. Lots of free useful info for electronic newbies lol!
So....

So, for those of you that were a bit stymied by the abbreviations and acronyms, like GMDSS, DSC, MF / HF, etc., I've got some basic info for you here, as well as links to very easy-to-understand videos and discussions of these things...
All for free...that you can peruse at your leisure....and if you desire to do so, you can download the videos, store 'em on your computer, and watch them whenever you need to (like when you're in front of your radio and aren't sure what to do)

{FYI, all of the videos are done with layperson sailors as the intended audience, not techo-geeks....so, there may be some repetition or "over-splaining", but if you find that's the case, just simply watch that video (or part of a video) in 2x speed...
Also, please note that all of these videos were made by me alone on-board, LIVE, as it happens, with no script, extemporanaiously...all demonstrations are LIVE as it's happening, in the real world, on-board a real offshore cruising boat (that I had personally sailed across the Atlantic, multiple times), sitting at the dock in S. Florida....
So, please forgive a few abrupt edits, etc...
Hey, it's all Free, after all!!
Thanks...}


For clarification and definitions...

GMDSS = Global Maritime Distress and Safety System
(first implemented in 1992, updated/modified in mid-90's, fully operational Feb 1, 1999)
It establishes the way all SOLAS-grade vessels ("big ships") and all the signatory nations (~ 162) communicate from ship-to-shore, ship-to-ship, shore-to-ship, etc., for all safety and distress matters....as well as establishes procedures for routine communications...

https://www.navcen.uscg.gov/?pageName=GMDSS
Global Maritime Distress and Safety System (GMDSS) - CCG - Search and Rescue

Have a look here:
https://www.navcen.uscg.gov/?pageName=cgcommsCall

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

https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y


And...some further definitions that may help:

SSB = Single-Side-Band = Used to denote typical maritime Voice communications...(although "technically" it's an actual "mode" of communication, most sailors just use "SSB" to refer to Long Range Marine Radio, as to differentiate it from the similar long-range "ham" radio communications)


SSB Radio = MF/HF-DSC-SSB-Radiotelephone....for the past 20 years, this is a MF/HF-DSC-SSB Radiotelephone....such as the Icom M-802....
(in decades long past, "SSB Radio" was just a marine "Voice" radio, but since the implementation of the GMDSS in the 1990's "SSB Radios", are actually "DSC" and "SSB" radios, covering all MF and HF maritime frequencies / channels)

M802 Single Side Band (SSB) - Features - Icom America
Icom SSB Radio Kits & Components


MF = "medium frequency" = Used to denote the "2mhz marine band"

MF-DSC = 2187.5khz (the GMDSS "Safety and Distress" MF-DSC frequency...although other MF-DSC freqs exist for other uses, few are used)

MF-SSB = 2182khz (the GMDSS "Safety and Distress" MF-SSB frequency....although other MF-SSB freqs exist for other uses, and are especially used with many MF Coast Staions)


HF = "high frequency" = Used to denote the majority of the maritime long-range communications frequencies between "4mhz (4000khz)" and "26mhz (26000khz)"....also referred to as "shortwave")

HF-DSC = 4207.5khz; 6312.0khz; 8414.5khz; 12577.0khz; 16804.5khz; are all the GMDSS HF-DSC Safety and Distress Calling freqs....(although other HF-DSC freqs exist for other uses, few are actually used)

HF-SSB = Used to denote typical maritime Voice communications freqs...(although "technically" it's an actual "mode" of communication, most sailors just use "SSB" to refer to Long Range Marine Radio bands/freqs, as to differentiate it from the similar long-range "ham" radio bands/freqs)

4125khz; 6215khz; 8291.0khz; 12290.0khz; 16420.0khz;
Are all the GMDSS HF-SSB Safety and Distress freqs....

https://www.navcen.uscg.gov/?pageName=cgcommsCall

Popular HF-SSB freqs are:
4.146mhz; 4.149mhz; 4.417mhz (4a, 4b, and 4c)
6.224mhz: 6.227mhz; 6.230mhz (6a, 6b, and 6c)
8.294mhz; 8.297mhz (8a and 8b)
{8.176mhz well used as AMSA/BOM offshore weather freq}
12.350mhz;
12.353mhz; 12.356mhz; 12.359mhz (12a, 12b, and 12c))
{12.362mhz and 12.365mhz are well used as AMSA/BOM offshore weather freqs}
16.528mhz: 16.531mhz; 16.534mhz (16a, 16b, and 16c)

https://www.navcen.uscg.gov/?pageName=rtchansi

Some well-used / popular freqs:
8.294mhz: 12.359mhz; 12.350mhz; Offshore / long-range nets and weather reports
4.045mhz; 8.137mhz Regional weather reports
8.104mhz SSCA Net
8.152khz Doo-Dah and Cruiserhiemer's Nets...


USCG HF Voice
NWS Radiofax
http://www.nws.noaa.gov/om/marine/rfax.pdf
USCG HF SITOR


SSB Nets & Frequencies
Weather-FAX Down-loads & SSB Voice Forecasts


In this YouTube Playlist is an old (1990's) video, video #13...
It shows the GMDSS design....there are a few errors in its narration, and it does show a few devices that are no longer used (but these errors/devices are noted in the explanatory description of the video...

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

(I will not post the video here on its own, as these errors would be confusing....I encourage all of you to watch the entire Playlist, so that you will have a complete understanding of the GMDSS and MF/HF-DSC comms)

In a nutshell....regarding the GMDSS:
Many of my fellow sailors use various parts of the GMDSS "system" on their boats today (VHF-DSC-FM Radios, NAVTEX, MF/HF-DSCX-SSB Radios, etc.) and some have more parts that they hope they'll never need to use (EPIRB), but will be glad they have it if need arises...
And, while most find the ~ $3000 cost of INMARSAT-C to be objectional, there are some experienced world cruisers that do have a "sat-C" system on-board, for weather, distress signaling, and 100% reliable low-speed sat comm data...

Parts of the GMDSS system that most find easy/affordable/useful (all within easy reach / affordable parts of the GMDSS for cruising boats...):

--- 406mhz EPIRB's (relatively inexpensive at $300 - $700, and easy to "sell" to cruising sailors..)

--- Marine VHF-DSC-FM (cheap and almost ubiquitous now-a-days...anyone that doesn't have a Class D VHF-DSC, REALLY needs to spend the few hundred dollars now!!!)

--- Marine MF/HF-DSC-SSB (HF-DSC is a VERY robust/reliable means of signaling.....and with reasonable costs of ~ $1800 new, ~ $1000 used, for an Icom M-802 MF/HF-DSC-SSB Radiotelephone....and simple-to-use, robust and reliable...it is an easy "sell", almost a no-brainer!!)

--- NAVTEX (inexpensive and very useful for most coastal sailors and/or those plying the Med, etc., with typical forecasts for waters out to 150 - 200 miles....but in some areas the forecasts are only for the next 24 hours, so other weather sources, such as HF-WeFax are recommended...) (and in US waters, the VHF-based NOAA Weather Radio system is widely used, so NAVTEX hasn't caught on in the US, as it has in Europe and the Far East...)
- WeFax....And while HF WeFax was not adopted officially as part of the GMDSS, according to a 2012 survey by the Joint WMO/JComm group, HF comms, DSC, voice, and data are used daily by a majority of ocean going vessels, and HF wefax being reportedly used daily by > 85% of them....so, for offshore/hi-seas weather info/forecasts beyond the "text" weather info provided via INMARSAT-C and some HF coast stations, HF WeFax still rules as the predominate "1st choice" when offshore, even in 2012, even for large ships / SOLAS vessels....)

--- Please note that while AIS transponders aren't officially part of the GMDSS, they are being considered and evaluated, and soon might be....

--- Further, AIS-SART's (AIS - Search And Rescue Transponders), are (since 2010) a part of the GMDSS....and there are some AIS-SART's GMDSS-certified....and these can replace the larger, more expensive, and less effective "SART" (X-Band Radar SART)...

So, some that have AIS transponders, AIS-MOB systems, or AIS-SART's now, might actually have another part of the GMDSS on-board, already...


Parts of the GMDSS that are a bit more expensive:

--- INMARSAT-C,
While INMARSAT-C might seem to some to be a bit pricey, at ~ $3000 - $3500, is a VERY viable communications tool to have on-board long-range cruising boats...as it gives, thru its FREE "SafetyNet" service, offshore/hi-seas weather info/forecasts (in plain text), position reporting and weather reporting thru NOAA and AMVER, and Distress Signaling....ALL FOR FREE....
NO monthly/annual subscription, NO Fees at all, until/unless you use it to send regular e-mails, and then you're just billed by the character/letter....
(and it is very robust/reliable....many orders of magnitude better than a handheld sat phone!!)


--- INMARSAT Fleet systems (such as F77) are pricey at $15,000 - $20,000 and are big/heavy, and use significant amounts of electrical power....
So, here if cruiser's desire hi-speed data / broadband internet access / etc., Iridium Pilot (and/or the new Iridium Certus system) or INMARSAT FleetBroadband systems (at ~ $4500 - $5000) are usually the typical choices....

--- Please note that some new INMARSAT FB ("Fleet Broadband") systems and Iridium Certus (running on the new IridiumNEXT network) are undergoing testing and are due to be GMDSS certified soon (2019?) and should be available for GMDSS installations in 2020....


--- SART's (X-band radar Search And Rescue Transponders) are reasonably priced at $600 - $800.....but are often over looked by many cruising boats, as they figure a working EPIRB in their liferaft will do them better...
And, if deciding between a second 406mhz EPIRB and a SART, I'd choose the second EPIRB!!! (but, if you're cruising in heavily-trafficked areas, with poor visibility, such as UK/North Sea, etc. then a SART would be a GREAT idea, and I'd recommend one before a second EPIRB...)



For further info / explanation of this topic here, and marine communications and weather services, etc., please have a look here at these YouTube Playlists, and these discussions...

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

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

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


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

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

Offshore Sailing (just for enjoyment!)
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nbwAGh5DKgTCj15iyl6qoY


EPIRB's --- how to better understand them --- and how to improve your rescue odds!
http://www.cruisersforum.com/forums/f13/epirbs-are-not-dead-epirb-activation-what-happens-how-to-improve-rescue-odds-146617.html


DSC Explanation...
http://www.cruisersforum.com/forums/f13/dsc-digital-selective-calling-explanation-169164.html

http://www.cruisersforum.com/forums/f13/new-hf-dsc-explanation-and-live-demonstration-videos-141406.html


Marine SSB Stuff...
http://www.cruisersforum.com/forums/f13/marine-ssb-stuff-how-to-better-use-proeprly-install-ssb-and-troubleshoot-rfi-etc-133496.html

Specific to installation
http://www.cruisersforum.com/forums/f13/hf-ssb-radio-proper-installation-tips-techniques-etc-198305.html



I do hope this helps clear up things?

Fair winds..

John
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Old 14-11-2018, 13:34   #79
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Hello to all,

I recently got a question from a fellow ham and future cruiser (he's boat shopping now), regarding the Icom M-802 and the Icom IC-7300....and asking my opinion....
So, here is what I sent to him...

~~~~~~~~~



Jeff,
I just saw your message....it was just a profile comment (that I never look at), but then see you are asking a question....and a rather important one at that!!


This might be more than you asked for....but here goes anyway!


Off the top-of-my-head, here are more than 10 things that differentiate the M-802 vs. the IC-7300...




1) First off, while the IC-7300 is becoming the signature ham radio of the decade, let's remember a few things about it, that can be problematic for HF maritime operations, on a boat...especially offshore / in remote locales...



a) It's a ham radio, and of course is not certified for any other radio service....and hence is illegal to use on anything other than the ham radio bands...


b) Being a ham radio (and again not needing to pass any certifications other than harmonic and Part 15) its spectral purity and transmit IMD are not up to the maritime standards, so even if you desired to flaunt the laws and attempt to use the IC-7300 on the marine bands, you'd likely be causing interference to other users..


c) It's an SDR-type radio....which in and of itself isn't a bad thing....but the inherent design means it is a software driven ("defined") radio, and as such can have some rather peculiar problems, as well as the architecture of its design lends itself to be easily updated/improved with new firmware and software....again, not necessarily a bad thing for hams on shore, but for a radio on an offshore boat that is a primary means of safety or distress communications, this is not such a great idea (at least not in my opinion), as it should be designed and built for its purpose not to stroke the egos of hams...


d) The menu-driven approach (especially using a touch screen) isn't very conducive to easy operation on a boat, especially when at sea....and in a tough situation (heavy weather, etc.) trying to use a menu-driven radio is the last thing I would be wanting to try!






2) Of course, the main difference between all "ham" radios and all modern "marine" radios is DSC...Digital Selective Calling...


There are no "ham" radios with DSC....and since DSC (which has been a part of the GMDSS since the 1990's) is the only way you can signal the > 80 HF coast stations and > 450 MF coast stations, and the 10's of thousands of SOLAS-grade ships....and except for signaling the USCG, AMSA, or NZMA (who do still monitor HF-SSB Voice channels) or calling vessels in US waters (who are still required to monitor ch. 16 VHF).....DSC has been the only way to signal anyone on the maritime bands now, for decades!! (of course "SSB Voice communications" is used for two-way communications, to talk/pass traffic, etc., between vessels, ship-to-ship; and ship-to-shore, or shore-to-ship; but this is done after signaling via DSC first, and coordinated via DSC....and then switching to the coordinated SSB Voice channel/frequency)....


Except for the scheduled cruisers' nets (and the aforementioned USCG, AMSA, and NZMA) there is nobody monitoring HF maritime comms with SSB Voice, only HF-DSC....and again this has been the case now for decades (the GMDSS was implemented in the 1990's, being fully operational and required on all SOLAS vessels and all signatory nations Feb, 1st, 1999)...


So, if you want to use the radio for any safety / distress communications, or for most maritime communication, then a MF/HF-DSC-SSB-Radiotelephone (such as the M-802) is necessary...


Please have a look at these video playlists...where you'll get a good idea of what the GMDSS is and particularly what DSC is and how-it-works...


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




Maritime HF Comms (in general)
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y




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




USCG communications page
https://www.navcen.uscg.gov/?pageName=cgcommsCall






3) Next in succession of importance is the design and build reliability of the radio, as well as easy-of-use (even for untrained persons), and simplicity of operation of the M-802 (its crappy manual notwithstanding)....it is an easy radio to use and it performs perfectly on all channels/freqs no matter who is using it....(you really can't screw it up)


See the M-802 Instruction Videos in the playlist above...







4) Then is the fact that it not only works well at "battery voltages" of 12.0dvc (and lower), it actually must maintain its full spec'd performance (meet the FCC Part 80 spec) when operated between 11.5vdc and 15.5vdc....there are no "ham" rigs that can do that....and most ham rigs will shut-down when voltages approach 12vdc....and most will have transmit distortion ("fm'ing") with voltages much below 12.6vdc...and will generally not have proper output at voltages below 13.2vdc...(and remember this is on transmit, at full-power, where you will also have some voltage drop in the DC power wiring....if you use large enough power wiring to keep voltage drop to 3%, at 13volts that is about 0.4 volts....so if your "house voltage is 12.6vdc, at best the voltage at the radio is 12.2vdc, best case scenario...)






5) Of course, "everyone" will say that marine radios are designed for the maritime environment...and they are....but to what extent does that make them "better" than most ham radios?? Well, that's an argument that I haven't solved....but suffice to say that the M-802 is certainly more rugged and better suited for the marine environment that the IC-7300!!


Also, the fact that the M-802 is destined to be used on-board a boat (in close proximity to its antennas and computers, etc.) it is designed to be more RFI protected than most ham rigs, and certainly better than most other consumer electronics....(I cannot compare this aspect directly with the IC-7300, but assume it is at best on par with most ham rigs...)


{understand that I not only have the radio just a dozen feet from the antennas, but that I regularly sit within 1 - 2 feet of the antennas, with the mic (and headphones) on extension cables, and talk on the ham and marine bands, without any interference / RFI / feedback....and while this is a testament to the excellent antenna ground / rf ground I have, it is also a testament to how good the M-802 and AT-140 are....try taking a modern ham rig, place it within 10' of a long (efficient) base-fed vertical wire antenna, and then sit next to the antenna with the mic on a long extension cable as let me know how well it works...}






6) Then you have the "compatibility" of the M-802 to other systems/devices (such as a GPS NMEA input, an external PACTOR modem, etc.)....although these can be used with the IC-7300, they are not as readily plug-n-play as with the M-802...






7) And, while you mentioned the "150 watts" vs."100 watts"....yes, this is only 2db of transmit power difference....but, 2db more power is 2db stronger of a signal....and when signals are marginal, this can make a difference!!



And, please note that the M-802 is rated at 150 watts output, continuous duty, on FSK (100% duty-cycle), as well as SSB/CW, and other digital modes...


And, produces a clean linear signal at 150 watts output....useful for both voice and digital modes...






8) Of course, the M-802 also has the advantage of having its control head (and speaker) remote from the main transceiver unit....this allows mounting the radio (main unit) in a safe location away from salt spray / moisture, and near to the 12vdc power wiring....and still have full 100% control and access to the control head (and speaker, and microphone) where you desire to operate from...
(I actually have a second control head, that I was going to mount out in my cockpit but never did....but, I do have an Icom microphone extension cable and headphone extension cable, that I run up to the cockpit, so I can use the radio while on watch at sea...the mic has "up"/"down" buttons and a separate programmable "control" button you can use to get a lot of functionality of the radio from, while still being 20' away from the control head...)






9) The M-802's built-in IF-DSP-based Speech Compressor is very good....adds significant talk-power and "punch" to your SSB audio, without any distortion at all (and without negatively effecting the radios transmit IMD nor spectral purity!).... Most ham rigs cannot do this...(but, I haven't looked at the IC-7300's speech processor system, but assume it's good??)






10) Although this last item is anecdotal / subjective, I (and others) get unsolicited reports of crisp / clear audio and a very clean signal with the M-802 on the ham bands where so many are used to crappy sounding and dirty signals, the M-802 stands out head-n-shoulders above the ham radios on-the-air!!






I do hope this helps clarify the differences....


Fair winds..


John
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Old 19-01-2019, 12:54   #80
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Well, here is another brief update/addition...

This time, regarding how "easy" it is to use your HF radio, as long as it's programmed well and you have at least a cursory knowledge of HF communications (such as garnered from some of my other videos)...


Although I still vehemently disagree with them, some of my fellow sailors have commented that there is some "magic art" to using HF radio....however, I do agree that with close to 5 decades of experience in radio communications sometimes what I perceive as "easy-peasy" can be daunting to novices....and this is the reason I decided to post my videos on Youtube over the years...


I made these videos myself....no director, no script, etc....all done LIVE in the real-world, as it happens (including some "opps" moments, just like real people make...), onboard a real offshore cruising boat, no "laboratory simulations"...

Also, over the years, I have said that if your HF radio is installed, commissioned, and programmed properly (and you've mitigated any on-board RFI), anyone with even a cursory knowledge of HF communications should be able to walk on-board at any random day and time, turn on the radio and be able to contact others within a minute or two...

I've also mentioned that if you know when/what times weather forecasts are transmitted for your area(s), you should be able to easily hear/receive them in no time at all...

I received some push-back from this as well....with some folks still saying that there is some "black art" involved....

Please note that while many see the "programming" as something that has little importance, in actuality with most non-tech / layperson folks, having the radio programmed and set-up properly (for their specific applications and their proposed cruising areas) can be of great importance!! Please do not just use the radio "as-is", program it and set-it-up correctly for your application(s) and your cruising area(s)....and things will be much easier!

I never wanted to argue the point, as this might just turn people off the whole process and they'd never get around to learning about HF radio.....but, I still stood by my opinion that if your HF radio is installed, commissioned, and programmed properly, a layperson-sailor with just a cursory knowledge of HF communications, should be able to walk on-board at any random day and time, turn on their radio and be able to contact others within a minute or two...

So, that is what I demonstrated in my latest video...


I show the exact time (on my wristwatch and radio display), that I walked onboard, turned on the radio, heard various stations (ham and maritime), contacted various stations, turned on other circuit breakers and switched on GPS and WeFax receiver, listened to multiple offshore weather broadcasts, received WeFax weather chart, etc. etc...all in about 10 minutes time (10:53amEST /1553z thru 11:03amEST /1603z) from switching radio on, including talking to two different stations, on two different bands, at two different distances, within a couple minutes....



I have also added this new video to my HF radio playlists...

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



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



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



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



I hope this helps some understand the importance of proper radio installation/commissioning, but especially proper programming (for the cruising area) of the radio's "user channels" for those "layperson sailors"...and of course, spending the time to learn the basics of HF radiowave propagation, as well as actually "knowing" your radio...




Fair winds and 73,

John
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Old 22-01-2019, 09:07   #81
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

I understand what you are saying but I think you are missing something of a more emotional issue. HF radios, and electronics in general, are like "magic" to a lot of people. They are intimidated. They can get over the intimidation through guidance like your youtube videos, courses, getting the Ham licenses, etc. Or not. It doesn't seem to be whether the human brain is capable of learning and doing it from my experience.


I have a science degree, a lot of technical work experience, got my licenses (I got the technical and my wife got the general), and we got an Icom M802 which I installed in a reasonably competent manner before we took off offshore. But without a doubt the most intimidating thing we had on the boat was the HF radio.



To this day I can't describe exactly why that was. But when we left the Straits of Juan de Fuca and turned left we still didn't know how to really use the radio. There just seemed to be too much to know. We didn't start to learn until we left San Diego and went to Mexico months later.



I could let myself feel inadequate about this but I have seen it over and over and over again with many others. I also know a lot of "radioheads" of find all this amazingly easy and they can't comprehend why it seems mysterious or difficult for others.



Setting up and running a good radar system is also very challenging for many yet it is actually much, much easier than using a HF radio. In my opinion of course. We learned to use ours and depended on it for communications and GRIB files across the Pacific. We understood how time of day and solar flares and other things impacted our use. We were frustrated when it didn't do what we needed it to do many times.



We still talk about how freaked out we were about using that darn HF radio when we left though. And since then I have read a ton about radios and listened to experts and still find that some of it is intimidating. We had never been sailors until that boat and had never been offshore. But we found that easier than that radio.



You have been amazing in helping out so many in demystifying HF radios - selection, installation, use. I can guarantee though that many radio noobs will continue to feel intimidated about something you find easy as crossing the road. At least you and others have provided resources they can use to sort it all out.
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Old 22-01-2019, 10:05   #82
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Maggie,
Thanks for the kind words!
Quote:
Originally Posted by exMaggieDrum View Post
You have been amazing in helping out so many in demystifying HF radios - selection, installation, use. I can guarantee though that many radio noobs will continue to feel intimidated about something you find easy as crossing the road. At least you and others have provided resources they can use to sort it all out.
And, fyi, you sound like my sister....she is 11 years my senior, and I used her (and, if you can believe it, my 97 yr old Mom) as my test audience for many of my videos...

Please to you and everyone....it is perfectly okay to be intimidated with this!! Really, it's fine!!!
Nobody is born with this knowledge...and few have a natural talent for it...so there is no problem being intimidated by it...
It's just that I hope that I can show others that the more they use it, the easier it gets...

And, of course I hope to pass on some good/helpful info AND (most importantly) pass on the easy way to do things, not the hardest way!!
That means starting with the basics that almost anyone can grasp....like what I wrote over the weekend to a gentleman in NZ:
Quote:
Originally Posted by ka4wja View Post
6) Or, if you want to start with the very basics....the first way of looking at HF radiowave propagation is to use these simple rules-of-thumb:
The higher the sun = the higher the freq used
The lower the sun (below the horizon is lower) = the lower the freq used
The longer the distance = the higher the freq used
The shorter the distance = the lower the freq used
Once you commit them to memory, the rest gets easier (I think??)



Any way, thanks again for the kind words....and fair winds!

John
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Old 23-01-2019, 09:09   #83
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

John,
I wish we had known about you when we were getting to know our HF radio. I have not seen your little rules for selecting frequencies. Excellent and simple. We had to figure them out the on the way the hard way from the Ham books and manuals.

Joe
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Old 26-01-2019, 16:39   #84
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

With all the advances in modern radio technology, I'm curious to know if anyone has used or attempted use morse code.
I will admit here to being old school.
I was just reading through this thread and nowhere do I see any reference to morse code. When all else fails, morse code can still get through. At least, back in my day, it did.
Back in the day, 20-25 wpm was the goal to get your " extra" license. The big prize !!
At first morse was quite alien to me, but with practice my speed increased and funnily enuff, it was easier to learn at 25 wpm than 5 wpm. After a while, you no longer counted the dots and dashes but instead started to recognize the " sound" of a particular word, much like learning a new word.
I've not kept up with Ham radio these days, but back in the day I had an older SEA 222 SSB and Kenwood 430 ham radio on my boat, they both shared the same tuner that came with the SEA.
WOM in Ft.Lauderdale still offered phone patches to land lines but are no longer around these days.
Just an old fart musing on bygone ways.
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Old 26-01-2019, 17:41   #85
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Mic,
1) Well, I'm not sure I can call myself an old fart, but I did learn CW (Morse) as a teenager in the 1970's and consequently have been a licensed ham more than 75% of my life!

And, while the ubiquitous Icom M-802 (as well as other modern "Marine HF radios") do make good CW rigs....[the M-802, of course has multiple IF bandwidths built-in, eliminating the need to buy optional narrow bandwidth IF filters for good CW operations]

The M-802 will also do full-break-in / full-QSK....and is easy-peasy to plug-in a CW key, or keyer...(pin #1 and #2, on the ACC connector)

My best friend (and fellow ham) is a CW nut, while I'm more of a "talker" (not a surprise to anyone who has read some of my long-winded posts)...
And, while I occasionally do make a few HF CW contacts from home (not on the boat)...and I have used CW extensively in my 144mhz EME/Moonbounce operations over the years (unfortunately Hurricanes damaged my antennas a few years ago), as well as some long-range tropo-scatter work (NON-enhanced 750m - 1000m scatter)...
But..

But, other than that, CW is just an after-thought for me...

Now, there are others here that do enjoy it, and are much better at it than I am! (I think both Scott and Bill are regulars on the 40m CW waterway net??)

{FYI, I too used WOM and WOO for decades....placed calls from all over the N. Atl, Med, Caribbean, etc...in the 70's,, 80's, etc...and FYI (for those unaware of the lack of international / trans-Atlantic telephone circuits even in the late 70's and early 80's....it was easier to call from the boat at $10/min, than waiting in line for hours at the "telephone office" for an "overseas line", so from the Western Med (Spain, France, Italy, etc.), and Eastern Med (Turkey, Greece, Egypt, Yugoslavia, etc.), it was easy-peasy to raise WOO or WOM on HF and have a chat, etc...(and then make a call, if you needed to, or just to check messages / traffic for your boat)....kinda brings a nice warm feeling thinking back to those days...
Oh, and BTW....one of the WOM tech ops (Wayne?) gave me and my two friends a tour of their facilities back in the 80's (their rec site was way out west in Dade, probably a shopping mal today...and their transmitter site moved to Ft. laud...loved those big 10KW amps......anyway, those were the days, huh?}




2) Also, we do need to remember that there have NOT been any maritime CW monitoring requirements (500khz) for maritime operations, not vessels or shore stations, since the GMDSS final implementation in Jan 1999....that's 20 years ago...and even for most of the decade of the 1990's vessels and shore stations were taking care of their requirements via dedicated receivers and not actual operators....

And, of course that freq allocation has been reassigned...
And, there are no other maritime CW Morse allocations...

Using MF/HF-DSC (which is multiple/repetitive 100-baud FSK-FEC transmissions in a 500hz bandwidth) to signal other vessels / coast stations is what is used these days, under the GMDSS....since Jan 1999....

Of course, SSB-Voice (in 2.8khz bandwidths / 3khz channels) and SITOR/NBDP (100-baud FSK / RTTY in 500hz channels), are used for maritime traffic, once contact is established via MF/HF-DSC....but, to be honest, most commercial shipping traffic is now done via Satcom, rather than HF radio...but "Safety", "Urgency", and "Distress" messaging is done via MF/HF radio (initial signaling via MF/HF-DSC, then usually SSB-Voice)



3) So, now that I answered your question
Allow me to comment on your thoughts about Morse getting thru when nothing else will??
Well, usually still true (assuming good operators on each end, and narrow bandwidths....like we use on EME)....

The 21st Century brought us MF/HF-DSC....and as I wrote, MF/HF-DSC is multiple/repetitive 100-baud FSK-FEC transmissions in a 500hz bandwidth, used to signal other vessels / coast stations...since Jan 1999, under the GMDSS...
While some may say that a CW / Morse signal can be copied down to a lower S/N ratio than an FSK signal, and this is of course true....but the way DSC is implemented, the SOLAS conventions / IMO decided the few Db was of little consequence, and was way over come by the FEC and repetitive nature of the signal, as well as the automation of the system...

So, in actual practice, in the real-world of HF maritime comms, CW didn't have any advantage anymore...


And now....in the last few years, in our ham radio world, we have low-speed / computer generated multi-tone / multi-phase digital modes, that allow the computer to copy signals with negative S/N!
Yes, JT-65, FT-8, etc. allow communications to be established between to station's computers, with actual RF signal-to-noise ratios (S/N) of -20db to -28db!!
And, that you cannot do with CW....(believe me, if you could, you could work 2m EME with a small yagi and 10 watts, instead of my four huge yagis and >1000 watts!)




So, to sum up...
Yes, there are some of us that still do dabble in CW, and some hams that just love it....but in the maritime world, it has long-since passed...


I do hope I clarified things for you??

Fair winds.

John


P.S. While my best friend regularly rag chews on CW, at 25wpm....I struggled with 13wpm, and just got to 20 by the skin of my teeth....but even cooler are some of my other friends (unfortunately most have passed on now), that used to rag chew at 40-50wpm, every day!!

I remember being at Jerry's once when we were sitting there talking with him (3 of us in his radio shack), and he had 40m CW on the radio, with the volume turned down so we could all talk easier....well, in the middle of our conversation he smiled and laughed, turned to his paddle and sent off a few words (at about 45wpm), and smiled and then turned back to us, without missing a beat of our conversation....he was having TWO conversations at the same time, one with us using is voice and ears, and one on 40m CW (at 45wpm) using his fingers and ears...
He was US military trained and worked as US military overseas air traffic controller, they passed traffic via CW / Morse back in those days (before I was born), and lives were at stake, so they copied 100% or else...

I miss him and my other friends that have passed, but I still keep 'em alive here and there!
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Old 26-01-2019, 19:24   #86
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

ha...well...to date me...back in the day...my day that is....my big leap into modern technology was being able to hook a small laptop computer to my boat radio's and being able to download weather fax maps..

Additionally....Cruisers back in my day used to hook with a guy called Herb....Herb Hilgenberg I think his last name was...can't recall anymore....His call was Southbound II...presumably his boat, though in later years he moved to Canada and would transmit from land using the same call sign.

He would follow several sailboats doing the Atlantic circuit and provide very detailed weather prognosis, but everybody that was sailing in the Atlantic would tune into his broadcasts and figure out what was going on. He would be on the air for an hour or more at a time, just doing weather, but I believe he is retired now.

He must have had access to a wide variety of weather information devices, because his forecasts could narrow it down to a few square miles.
Herb broadcast via SSB. I often spoke with Herb back in the day. His weather reports were 1,000% better than the NWS of the day. He had a very loyal and ardent bunch of followers.

On Ham, there was the waterway net at 7...something....ever morning around 6-7 am and off course, during the afternoon, there was the 14,300 high seas net, with several hams willing to phone patch you in to wherever you want to call. The waterway net connected with local cruisers doing the ICW, but boaters in the Caribbean could take part. There was also the Pacific net and several others.

My girlfriend of the day had a dad who was an old time ham enthusiast. Had a gazillion antenna's sprouting from his house and one room of his house looked like a WWII command post, he had so many gizmo's and gadgets in there. He could send and receive CW at blistering speed. Off course, he wanted to know the well being of his daughter so he would always connect with us on prescribed bands at prescribed times. That man knew his way around the ham bands. He was a marvel.

Ah well, I still stay in touch with some cruising folk, but the modern cell phone coverage makes ham almost obsolete. Cell phone and the internet is the modern day ham. Sad but true.

Nonetheless, I follow this thread with interest. Thank you.
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Old 07-02-2019, 20:54   #87
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Power / SWR Meter for Marine HF-SSB Radio (how-to better use SSB & troubleshoot)

I've recently gotten a few questions regarding the Power / SWR meters I have permanently flush-mounted on my Nav Station....
And, I thought some might find this info useful (not really the info on my power/swr meters, but on what you might desire or need...or not need??)

So, here is what I just wrote...


The meters you see flush-mounted on my Nav Station are Daiwa CN-410m for my M-802 (15w/150w from 1.8mhz thru 150mhz)....
And, a Daiwa CN-460m for my M-602 VHF (15w/150w from 140mhz thru 450mhz)...

Unfortunately they are no longer imported into the US....and are in short supply in Japan....so...
So, if those are the ones that interest you, you're out of luck...


But....two pieces of good news...

1) Daiwa CN-801HP or CN-901HP, are both good meters....but, a bit bigger and a bit more complicated to "flush mount"...



2) But, you may not need to permanently mount a meter on-board....
You might not be fully aware of the features / displays of the M-802?
But, fyi, most sailors find that while they might desire permanently mounted power/swr meters, they find that might not really need one...

I agree that having one is very nice, and I do recommend them....but might not be necessary...

'Cuz...

Fact is, the M-802 actually DOES have power output metering AND a high-swr indicator (as all other Icom HF Marine transceivers have had for > 20 years)...

No, it does not read-out the exact wattage number on a display, nor is there any numerical swr indication...but...

---- But, the M-802 (as well as other Icom HF Marine rigs) does have an 8-segment bar-graph display that is surprisingly fairly linear, and accurate....

(AND in the M-802, at least, the LED bar-graph is fast enough to show as a "peak-reading" display, so that it does follow normal speech fairly well, and therefore is actually a darn good indication of the radio's actual "SSB Talk Power", i.e. whether the M-802's DSP Speech Compression is On or Off, as well as how "loud" your audio is on-the-air...
And, except for the fact that I know how my Daiwa CN-410 "average-reading" meter should read under normal voice, the M-802's internal meter is better for showing the voice peaks!)

The M-802 illuminates one segment for every 15 - 20 watts of output power...

All 8 segments = full output - 140 - 150 watts

This should be seen when full carrier is transmitted, such as when pressing the microphone PTT button in "FSK" mode, or when transmitting a CW carrier....and also, 7 - 8 segments should be illuminated when you whistle into/across the microphone in "SSB" mode...

In CW or FSK modes:
1 - 2 segments = 10 - 20 watts = "tune power"
1 - 2 segments = 15 - 20 watts = "low power"
~ 4 segments = 60 watts = "med power"
8 segments = 140 - 150 watts = "hi power"


In SSB mode, the exact number of segments illuminating when speaking normally will vary, depending on 3 things:

a) Whether the M-802's internal DSP Speech Compression is turned On or Off...
(If it is On, you will see approx. 7-8 segments on voice peaks, and typically 4 - 5 segments on normal speech....
If it is Off, you will see 4 - 5 segments, at most, on voice peaks, and typically only 1 - 3 segments on normal speech)

b) Exactly where you place the microphone...
(1" to 2" away from your mouth, and speak directly into the small electret mic element opening, is best...)

c) Your exact voice..
(some talk louder, and annunciate well, some don't....and typically women have a better SSB voice than men do!!)


---- As for an SWR indicator....well, all marine radios fall short....but...

But, the M-802 (like other Icom HF Marine rigs in the past 20+ years), does have an "hi-SWR" indicator...

The display that normally shows "TUNE" will flash "SWR" when the swr reaches approx. 1.7:1 to 1.8:1, and "SWR" will stay illuminated if the swr is 2:1 or higher...

Also, the M-802 (like all other modern solid-state HF radios), will reduce its output power when presented with a high SWR....this is known colloquially, as "SWR Fold-back"....


And, while I don't have the exact specs at my finger tips, I do know that at 2:1 SWR, the M-802 will fold-back to approx. 110 watts....and at 3:1, will fold-back to less than 50 watts...and at much higher SWR's (such as when you have a tuner failure, etc.) the M-802 will only output approx. 20 watts...

So...

---- if you know the amount of power your radio outputs based on how many segments of the display are illuminated...

---- and you understand the radio will indicate when an SWR of 1.7:1 is reached (by "SWR" flashing) and when an SWR of 2:1 or higher is reached (by "SWR" staying illuminated)...

---- and you understand the radio's SWR-Fold-back specs....

Then...
Then, you can certainly make simple "proof-of-performance" tests, and do basic RF troubleshooting...all without any external power/swr meter!!

Again, this is NOT as good as having a real external power/swr meter, but all of the pertinent info is right there for you!!


The REAL problem here is that Icom does not have this detailed info in their owners manuals!!!
And, unless / until, many of my fellow radio nuts pass this on to as many sailors as possible, then few sailors will know all of this!!!



I do hope this helps!!!

Fair winds...

John
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Old 07-02-2019, 21:51   #88
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Thanks for this info.
I have been thinking of panel-mounting my Diamond SX600, (readily available) which hooks into both VHF and HF, but the switch to select between them is unfortunately located on the back of the unit. I’m sure the switch can be relocated - with some difficulty. It is just enough of a pain to connect it “freestyle” that it rarely gets used unless something is really wrong.

I’ve been assuming that leaving this thing in-line would result in some loss of output power, but wasn’t sure how much, or how to figure it.

Also, FWIW, the EM-Trak AIS unit does have a built-in SWR meter for the VHF side of things, but the only way to read it (AFAIK) is to hook up a laptop with the included software. They are also the manufacturer of Raymarine’s unit, so maybe that works too?
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