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Old 23-10-2016, 06:44   #61
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Quote:
Originally Posted by btrayfors View Post
Yep, they both should work well.

Bill
Thank you!
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Old 14-05-2017, 16:26   #62
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Answering another question here, the poster said there should be a sticky with a shopping list of what's needed...
And, I might just start working on that...
But, until then, here is what I wrote to him, regarding an M-802 install on a bene 411, going on a circumnav...
Enjoy...

John


Safc,
Thanks for replying with more details...and I'll answer you in specifics as well...

[I REALLY mean a BIG Thank You, for giving me all these details!!!
It really helps when answering questions!!]

In addition to what I write here, there is a "sticky" right at the top of the Marine Electronics page, that has almost all of this info in it!!
http://www.cruisersforum.com/forums/f13/marine-ssb-stuff-how-to-better-use-proeprly-install-ssb-and-troubleshoot-rfi-etc-133496.html

Also, if you want a shopping list....that's a problem, because every boat is different, and every sailor might have a different application / desire...
But, the closest you can come is to contact someone that actually sells/installs marine HF radio systems on sailboat...
Such as Gary at Dockside Radio...
http://www.docksideradio.com/Icom%20SSB%20Radios.htm



1) But, first off, I'll address the "primary HF antenna" choice...
I understand your reasons for not wanting to use your backstay for an antenna (if you get dismasted, there goes your HF antenna)....and of course good rigging insulators are very pricey!!
And, if you've made your decision, you're good-to-go...

But, you should understand a few other things about this as well:
a) a dismasting is VERY rare....I've seen the aftermath of a few over the past 40 - 50 years, and every one was caused by faulty or corroded rigging wire or wire terminal, not because of a rigging insulator, nor a 360* roll-over...(yes, a 360* roll-over can happen, and it can tear your mast off, but they are damn rare!)
{btw, unless you're racing, or planning high-latitude sailing (especially out-of-season), you are much more likely to experience calm weather / light winds, than "storm force" winds...and this is also why dismastings are rare..}
b) when a dismasting occurs, the chances are very good that any SSB "whip" antenna (whether the venerable 23' Shakespeare whip, or Morad, etc.) will be swept over as well, or at best severely damaged...
c) just about any length of wire, stretched-out and/or supported some how above the deck, etc. can be used and an emergency antenna...
(I actually have a 25' length of GTO-15, and an old MFJ manual antenna tuner, in a big zip-lock bag, as my emergency HF antenna, and also have a couple of deep-sea fishing rods, usually stowed below deck, which could serve well as antenna supports)
d) if you have any reservations about rigging insulators, use the Hayn Hi-Mod insulators....they're "fail-safe" and will last a lifetime...but they are very pricey!!!
e) I believe the Bene 411 has twin backstays? So, while loosing a backstay isn't a good thing, it's certainly possible to break one backstay, and still have the mast standing fine...(probably not good to stress the other stay, with lots of canvas, but the mast could still be standing fine)


Okay, now that I got that out of the way, there is no question that a "longer" antenna (40' - 50') versus a shorter antenna (23' whip) will work much better on the lower frequency bands (4mhz - 12mhz), because of the antenna's efficiency...and lower losses in the remote tuner...and because of the antenna's generally higher-impedance, making some of the antenna ground losses less detrimental...
And, with the majority of maritime HF comms on 4 thru 12mhz, and majority of cruising nets on 4 thru 8mhz (and majority of sailing ham nets on 7mhz and 14mhz), and with the 11-yr solar cycle on its 3 - 4 year down-swing, it makes sense to optimize your primary HF antenna for these bands....hence an antenna of 40' - 45' overall, is the generally accepted standard that all others are compared to...

Here's a internet-sourced photo of a Bene 411...(I think??)


The fact that the Bene 411 backstay length is about 56' - 58' (???) putting a upper insulator a few feet (~ 6') from the top, and a couple feet of GTO-15, would give you a fairly good ~ 50' long primary HF antenna, whether you use a lower insulator or not...or most-typically, placing the upper insulator about 10' - 15' from the top, to allow and overall antenna length (including the GTO-15 wire to the tuner) of about 40' - 45'.....
BUT...

But, the good news is that you can also rig a long "rope-tenna"...
Do NOT buy a "rope-tenna", you can build your own for 10% - 20% the cost, and it will work just as good!!

While you can use GTO-15 wire the whole way (40' - 50'), but that is costly, and you could just use any good quality 14ga insulated stranded copper wire (I prefer PE insulated / polyethylene insulated stranded copper wire....and most will also recommended "tinned" copper, as well..)
You just take a length of double-braided polyester line (Sta-Set, etc.) that is long enough to secure from the mast head to the transom or stern-rail, etc.....and then insert a ~ 40' length of this copper wire inside the line (sealing up the top end of the wire), and either the bottom end of the wire exits the double-braided line and connects to a short run of GTO-15 wire that runs to your remote antenna tuner, or if the wire is of high enough voltage rating (such as, if you used GT-15 wire the whole way) goes directly to the tuner...

And, that's a "rope-tenna"!!
That's all there is to it!!
There is no magic, nothing precision at all!!


But, you can also make up an "alternative backstay antenna", which uses a length of "lifeline wire" or smaller-size rigging wire, instead of the above-mentioned double-braided line and copper wire...and, then with a short length of GTO-15 going to your remote tuner...
This is a great, heavy-duty, long-lasting approach...(and has been recommended by Bill / "btrayfors" for years here and elsewhere)

Just like the "rope-tenna", this works very well, and is even more weather-proof / fool-proof, than the rope-tenna...


But, as you can see that if you already have two backstays, and then want to add a "rope-tenna" or "alternatve backstay antenna", you've got to find room for it, keep it from interfering with your sails, keep it from shading solar panels, etc. etc...
So....
So, I insulated one of my backstays, and am very happy with the results, going on 13 years now on my current boat, see photos...note the first pic is really old, before I even got my solar array up! But, note that my "SSB Antenna" (my insulated backstay) runs right past my solar array (four 130-watt Kyocera panels), and is just a couple inches away from a couple panels...with no RFI issues, either way!!








See post #17 here...
http://www.cruisersforum.com/forums/f13/optimal-ssb-antenna-e-147034-2.html#post1838896

And, this entire thread...
http://www.cruisersforum.com/forums/f13/optimal-ssb-antenna-e-147034.html


And, here is some more...
http://www.cruisersforum.com/forums/f13/recommended-coax-for-triatic-stay-ham-antenna-147339-2.html#post1840889





And, here is a bit more....from Practical Sailor...
https://www.practical-sailor.com/blog/Calling-Mayday-on-an-SSB-11559-1.html

So, as I continue to ramble on and on, you're thinking "why in the world can't I just use a whip. because this rope-tenna or alt backstay antenna stuff is way too complicated?"
Well, the answer is, of course you can use a 23' whip....I just wanted you to be aware of why it might not be the best choice...



2) Now, how about I answer your question about what to use for a HF-DSC-receive antenna??
{VHF-DSC uses your primary VHF antenna, along with your VHF-FM Voice communications...and this has nothing at all to do with this discussion...}

HF-DSC receive antennas do NOT need to be mounted on the mast....
Most are either a simple piece of rigging wire, or a stern-rail-mounted / arch-mounted SS whip antenna...
{please note that this HF-DSC SS whip antenna looks like a VHF marine antenna, but it is NOT!!!}

I've personally used two different DSC receive antennas...

a) The first one was a Metz stern-rail-mounted 54" (1.4m) long SS whip antenna, specifically designed just for HF receiving of HF-WeFax and HF-DSC..
It worked okay, did the job, and was inexpensive and unobtrusive...(but, not that great in the WeFax receiving, and just "okay" in the DSC-receiving...so, I went to onto plan "b")
http://metzcommunication.com/weatherf.htm
http://metzcommunication.com/

http://www.docksideradio.com/Icom%20SSB%20Radios.htm

http://www.landfallnavigation.com/ecr201.html
http://www.radios.net.au/marine-radio-packages/marine-antennas/metz-weatherfax-/-dsc-receive-antenna-only-135cm-high/prod_1293.html


b) My plan "b" was to use one of my aft lower shrouds as my HF-DSC Receive antenna / HF-WeFax Receive antenna....and it works great!!
It turns out to be about 22' long, and I insulated the upper end (just to keep it electrically separate from the rest of the rig, and eliminated any potential RFI pick-up), and have it fed with coax directly from the chainplate....just the center-conductor of the coax attaches to the chainplate,....(while this simple set-up works great, you can do this in addition, as I have, about 8 turns of the coax around an F240 toroid as a cheap balun.....or you can simply use a cheap commercial-made balun...)

I have written about all of this, in some detail, in the past....have a look here...
See post #10 here...
http://www.cruisersforum.com/forums/f13/ssb-dsc-antenna-idea-175681.html#post2257738

And, see post #12 here....
http://www.cruisersforum.com/forums/f13/ssb-dsc-antenna-idea-175681.html#post2258484

And, see post #2 and especially post #12 here...
http://www.cruisersforum.com/forums/f13/wire-antenna-for-hf-dsc-147650.html


c) A plan "c", would be the same as "b", but without insulating the shroud...
Others have done as I have, but NOT insulated their shroud, and in effect have used their entire rig as their HF-DSC receive antenna....and they report good results....
(If you decide to try this, I advise doing a receive RFI check and signal strength check, to compare the overall signal-to-noise ratios between your "primary HF antenna" and your HF-DSC Receive antenna....thereby proof-of-performance testing this set-up...)


Now, as you know, I'm a radio nut....and as such what I do (and some of what I recommend) might be a bit over-the-top, and might be more than most others would consider "adequate"....
SO...
So, while my plan "b" works for me, and I get many "all-ships" HF-DSC calls, and a few Distress HF-DSC calls, and I would recommend this for someone doing a circumnav, etc....the 54" Metz whip (plan "a") should work fine for most sailors, as an HF-DSC-Receive antenna...




3) Virtually no difference between the AT-140 and AT-141....(I think the 141 is supposed to have a "back-up 2182 manual-matcher", built-in???)
But, whatever the case, it will not matter at all to you, so either one will be fine...
But, I will caution you to not place the remote tuner (AT-141) near the autopilot corepak/course computer, nor near the fluxgate, nor autopilot wiring!!
Understand that the antenna starts right at the remote tuner, the GTO-15 wire (or whatever antenna wire you use) IS your antenna!! And, you cannot place any ferrites on this!!!
So, placing the remote tuner (which is the start of your antenna) near the autopilot is not a good idea....as this can cause transmit RFI issues, meaning your autopilot might malfunction / disconnect / change course / etc. when you transmit...and this is of course not a good thing!!
(fortunately the good news is that most autopilot course computers don't generate much RFI of their own, but sometimes the drive motors do...)

If you can mount the AT-141 elsewhere, I would do that....
But, remember that other system can be cause of RFI as well....such as refrigeration compressors causing receive RFI, so try to keep the AT-141 away from them too...
There is no need to have the radio and tuner on the same side of the boat, so if there is another location for the AT-141, choose that other location....or make some on-air transmit tests, before permanently mounting/installing the AT-141, to verify that all is good there...


4) On a similar vein....RF ground / Antenna Ground (sometimes called a "counterpoise")
Wow, what a long, involved and usually controversial subject!!
But, it shouldn't be so...
Please know that we are talking about a matter of degree.... i.e. how well one system works versus another....
(even systems with NO rf ground / antenna ground work...it's just how poorly versus how well other systems work...)

a) First off, your best overall rf ground / antenna ground for HF radio on a small boat is the sea water (unless you have an aluminum or steel hull)...
Sea water is a great conductor of RF energy, and makes an excellent antenna ground...BUT...
But, you need a short, low-impedance connection to some decent underwater metal (like Dynaplate or bronze thru-hulls)....
This is typically done with a 3" wide copper strap, of 8' - 10' in length or less (shorter the better!!) to a Dynaplate (or two) or bronze thru-hull (or two)....
If you do not have bronze thru-hulls (mine are Marelon), or do not have any in close proximity to where the remote tuner is located (more than 8' away), then Dynaplates are a great underwater connection! (they are pricey!! but they do work well....but work no better than a solid bronze plate...

b) If you cannot make a decent low-imp connection to the sea water, your next best approach is use whatever you have on-board already...
-- Alum toerails make a good counterpoise (but, you will need to drill/tap, and attach to the raw alum, not try to make a connection thru the anodizing)...
-- SS stern rail, pushpits, pullpits, lifelines, etc. all make good counterpoises as well...
-- Some boats have "rubrails", and they make good counterpoises as well...
{although, I prefer to use copper strapping to attach to any/all of these, you can use copper wire to good results...}

-- tanks, especially large, flat tanks, make good counetrpoises too...

-- external lead keels are "okay"....but mostly only "okay" / "marginal", as they're usually quite a ways from the tuner and with such a long run, the connection to them does as much of the antenna ground current conducting as anything...so, while attaching some copper strap to a keel bolt is good, unless this is rather close to the tuner, it's only an "additional" counterpoise, and not your primary one...


c) Artificial counterpoise / radials...
These are quite easy to make, and install...
Basically, just a bundle of wires from the tuner's ground lug, strung out as best you can thru the bilges, and/or under the cabin sole, and/or under the cabin headliner, under-deck, etc...
You can makes these very cheaply (less than $5 USD, or for free), in less than 5 minutes...and they will work better than the KISS Ground!!
While cutting them to approximate 1/4-wavelength on some of the popular marine HF and ham HF frequencies is good, please understand that once placed in close proximity with each other, and close proximity to ground, and close proximity to other wires and metallic objects, their "tuned" resonance no longer exists....

The KISS Ground is just a few wires stuffed into a nice black hose....
It has no real tuned resonances (see my quite detailed test results)...
https://www.ssca.org/forum/viewtopic.php?f=5&t=13490&start=75&sid=8aabedb8416 016bb34a486e68809ff01
Re: KISS-SSB Counterpoise
You can build your own version for about $5 USD (or free) in less than 5 minutes!!



5) As for videos....
Please watch these playlists....they will help

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


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


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


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


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



I hope this helps...

Fair winds...

John

P.S.
Here are some other offshore sailing videos....just for fun...
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nbwAGh5DKgTCj15iyl6qoY
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Old 23-05-2017, 14:21   #63
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

During a recent discussion regarding a sailor not being able to make contact with a new and newly installed M-802, it was clear that except for the speech compressor being turned off, there was little chance of the radio being the cause of the troubles....

Although, the 12vdc wiring was less than optimal, most of the problem was the weaker talk power without the speech compressor On
IC-M802 Compression
And lack of understanding of how HF radio communications works...
Maritime HF Comms
https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y
HF-DSC Comm
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX
Icom M-802 Instruction Videos
https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr
Offshore Weather
https://www.youtube.com/playlist?lis...zdjTJjHlChruyY


A local Icom dealer had a tech come out to the boat, switched On the speech compressor for this sailor, and briefly showed him how to make contacts....
Problems solved...for the most part...

But, I got to thinking....what if everyone could benefit from this....like a "teachable moment"???
So, here is a link to that thread....and some of my final observations there...
New ICOM M802 SSB won't transmit - urgent advice needed


JR,
In just our messages back-n-forth you seem like a good guy, and shouldn't mind everyone using your experiences (and my observations, too) as a "teachable moment"??
Anyway, here goes...

1) As I've been saying for years (decades??) HF radio communications are actually quite easy and reliable, and fairly predictable, too....and while these words surprise many laypersons, once they learn about it, they usually see that these are truism's...

But, just like most things in life, we are not born with this knowledge / experience....we must learn it and do it....like sailing itself!
As I continue to preach, you needed to learn how to sail, navigate, trim sails, flush the head (and repair it), etc. etc....as well as so many other things in life, like learning to walk, talk, read, math, etc....
Why do many think learning about radiowave propagation and HF radio comms would be any different??
They simply need to learn the basics, and use the radio!
I am still amazed that so many of my fellow sailors think/say that since they can't just tap on an App icon, and get what they want instantly, that "this stuff just doesn't work", or "it must be broken"...

In addition to my words above (and for many years) and my continued observations, please read what JR wrote here:


Quote:
Originally Posted by jr_spyder View Post
Well I've got good news. I called my local marine electronics hop and they sent a technician over mid-day today. He enabled the compression feature very quickly and then checked everything out. He was a very skilled and dedicated HAM so he briefly opened the HAM channels and made a contact. He thought everything was working as it should. He disabled that HAM capability before he left. Maybe I'll get back to that someday.

Later I was able to reach WLO on 1212 with a reasonably good signal. I'm much happier now with the rig and feel more confident in it doing its job as I learn more.


You see....knowing just a little of what the radio does, somewhat how the radiowaves propagate, and some basic instructions on operating / talking on the radio...JR successfully made contact with a station about 1200 miles away, and feels confident that radio is doing its job (which it is doing well, now that the speech compressor is turned On)!!


Now, I would have insisted that this guy proof-of-performance-test the whole system, and provide JR with a chart showing power output, reflected power, VSWR, DC voltage/power to radio, etc. on each and every marine MF/HF band (as well as the ham bands), and an observation of how these exact power output measurements correlate to the radio's own power output display....and a list of various stations contacted on-the-air live, the times/freqs and their locations, as well as their signal strengths and the signal reports they gave your vessel...
Also this should include any observations of on-board RFI (both transmit and receive RFI), as well as any anomalous behaviors of the radio system, or any other system on-board while transmitting...
But....

But, hey at least he has confirmed that it is working!!

Yes, he got professional help...but how many of you learned advanced mathematics without a teacher?? or even never watched a sailing video??
So, we ALL get help....we all learn stuff everyday, from everyone...
{As a teenager at a Mensa meeting, I was reminded that "Everyman is my teacher, in that I may learn from him."....but, as I got older I realized that not only does this go both ways, but also requires BOTH parties to be willing to learn and teach....
I know, I know....way WAY off topic! Sorry! }

My point here, to everyone, is:
Don't think everything in life is now done for you by some electronic microprocessor....don't forget to use your own "microprocessor" (your brain) and learn!
AND...

And, use the radio!!!
The more you use it, the better you be at using it!!
Yes, read the threads and watch the videos....they are good tools to help, but using the radio is where you will actually be putting this knowledge to work AND learning at the same time...
So, use the radio!!
[As I wrote earlier, the IMO (international Maritime Organization) and the GMDSS recommendations, clearly say that mariners should regularly use their HF/MF-DSC-SSB Radiotelephones, for routine signaling / messages, so that they will be familiar with the system in times of Distress and easily recognize radio system issues, before they fail at critical moments!!
And, these are for professional mariners, with specialized training....so, pleasure-boat sailors with little to no professional maritime / communications training should take these recommendations as "requirements"....
Use the radio!! ]


2) As for the technical stuff...
I caught some flack for a recent comment "that anyone should be able to walk on-board, turn the HF radio on, spin the dial, and make contact with someone within 30 - 60 seconds"....
Some have called bullshit on that....so, allow me to clarify..

I stand behind my words, but need to add some qualifiers...
a) this assumes you're within a couple thousand miles of civilization
b) using ham and/or maritime freqs (especially ham for HF Voice comms and have Maritime HF-DSC capability)
c) have a working radio system on-board
d) have more than a basic understanding of radiowave propagation
e) have more than a basic understanding of who is listening where, what band/freq. what time-of-day, etc. etc.



3) As an example....how about I eat some of my own words from a couple years ago...
Using my experience from yesterday afternoon (22 May 2017)...
{a couple sentences of background....for 25 years Herb Hilgenberg ran his weather net, primarily on 12.359mhz...and during his last few seasons, I was there on-the-air monitoring from my boat at the dock, and assisting with radio relays / radio issues....part of my routine was to check propagation (and sometimes I got bored, even during the Net, so would spin the dial to see what else was on-the-air)...and sometimes, some boats would be "off-frequency" a bit, and I'd tune around to see....and one afternoon I bumped into Australian Maritime Voice Weather Broadcasts on adjacent channels, 12D (12.362mhz) and 12E (12.365mhz), form 11,000 miles and 9600 miles away...sometimes I'd check 16.528mhz as well...
(Oh, and I also heard them at nighttime on 8.176mhz!!)}

So, I've occasionally commented that if you know about radiowave propagation, and have little (or no) RFI, (and a decent antenna system), you can communicate with stations a long ways away, without much trouble....
Schedules and Frequencies for HF Marine Radio Voice Services
Australia Marine Radio Broadcast Areas

Now, nobody would recommend trying to contact AMSA from Florida, especially on 12mhz...but, just the fact that I would hear and understand their weather broadcasts from 1000 watt transmitters 9000 - 11,000 miles away, is telling of my comments that you can make HF communications work, if you know the "when" / "where" / "how", etc...

So, here is where I must confess my own forgetfulness...

A few years have passed and the solar cycle has been declining steadily during that time, and we are headed further down for the next 2 years and another 2 years (maybe even 3 years) after that of the doldrums, before things start to improve....so, propagation has changed since I was hearing those Australian BoM / AMSA weather broadcasts so clearly...
And, with higher A-indices this month, etc., things have changed...
And, yesterday, when I tuned in to listen to them (as I was hoping to talk to JR on 12.359mhz, I tuned around to hear my Australian weather broadcasts), I found them weak and barely readable...(I forgot to check 16.528mhz, but suspect that I would've heard 'em there, too)

Now to be clear, VMC, in Charleville, AUS, is 9600mi (8350nm) from me, and VMW, in Wiluna, is 11,170mi (9700nm) from me....and I'm using just my 60' backstay antenna....so, nobody would expect "perfect copy"....
But, things on the higher bands are getting tougher these days!

AND...

And, then...


4) And then, I was on 40m (7mhz) ham band just tuning around, waiting for the Doo Dah Net on 8.152mhz, and heard some stations quite a ways away....remember this was afternoon, about 3.5 - 4 hours before sunset, where D-layer absorption is still pretty high, and I made contact with stations in west Texas (1000nm away) and Connecticut (900nm away), on 7mhz, during the afternoon....now to certain these guys had great stations and their signals were stronger than everyone else's, but still these distances, at this time of day, on this band, was unheard of just 2 - 3 years ago...
So...

So, here again, I'm reminded that things have changed...yes, they will change back...but for now and the coming 2 to 4 years, we can expect 12mhz to be useful less (and mostly for longer ranges) and 8mhz to be useful more....
Although NY Radio Volmet (13.270mhz) is still booming in here, as well as NMF WeFax on 12.750mhz, just be aware that one band lower is also working now for daytime use, well beyond NVIS range...

So, when watching my videos....any comments about "exactly" what freq/channel should be understood to be based on the solar cycle at that time, and know things do change a bit....
Still use the highest freq/channel possible...it's just that it might be one band lower than is shown in the videos, and in the coming 2 - 4 years, I will try to remind everyone!



5) One final caveat, reminded by my own observation yesterday...
Anything can happen!!
Yesterday afternoon, as usual I found USCG WeFax transmissions loud and clear from NMF (Boston) on both 12mhz and 9mhz (12 was stronger, of course), and from NMG (New Orleans) on both 12mhz and 8mhz (about the same, but slight edge to 8mhz, less fading...)
But, when tuning around, I found USCG WeFax transmissions on 13.089mhz (the coast station transmit freq of ITU channel 1205, assigned as an SSB Voice working channel to the USCG)!!

With all US Mainland USCG HF transmitters now being remotely controlled from CAMSLANT / NMN in Virginia....I assumed they accidently patched the WeFax input into the wrong transmitter (cuz NMF, NMG, and NMC were all on-the-air transmitting at the time....and I surmised that they simply / accidently switched the WeFax input to their NMN 13.089mhz transmitter...
I made a phone call to them (CAMSLANT / NMN) in Virginia and told 'em what was going on....after a few "hmm's" and "oh's", they said, "sorry, we must've gotten something switched wrong"...
After a few minutes of them discussing what to do, I said I had to go and said my goodbye....I assume they fixed the problem, but I really did need to go, so I didn't stick around on-the-air to see...

My point here is:
Anything can happen!!
Even the USCG screws-up communications sometimes....
Now, to be clear this was NOT their GMDSS transmitters, so nobody's safety was effected....and as soon as they needed to use that particular transmitter for something (they had a SSB Voice Offshore Waters Weather Broadcast coming up in an hour), they would've seen this error and I assume fixed it without incident....just saying...



Okay, enough of my ramblings....


To sum-up...
Most problems with HF systems on-board, if the sailors are new to HF comms, can be traced to lack of education regarding HF comms and not to equipment failures...
Secondarily, it is the installation / wiring / programming / commissioning / etc that makes the stuff work...



Fair winds to all...

John


~~~~~~~~~~


Hope this helps...
Fair winds to all...

John
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Old 08-08-2017, 11:46   #64
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Re: Marine SSB Stuff (including some Sailmail info / setting drive levels, etc.)

I got a nice e-mail saying thanks for all this info here, and also asking me for any updates. I smiled at that request, as radiowaves still travel the same as they always have...

And, since the initial implementation of the GMDSS in 1992, and its Jan 1999 international compliance requirement for all signatory nations and all SOLAS vessels....
And, with the USCG finally changing their Voice SSB Radio watchstanding freqs/schedule in 2005 (note that they are NOT required to actually have a "Voice" radio-watch, at all, only DSC)....
And, with the USCG finally giving up on all MF / 2mhz comms, ceasing their 2087.5khzDSC watch and their 2182khz Voice watch, in 2013....

https://www.navcen.uscg.gov/?pageName=cgcommsCall
(be sure to read and print-out this USCG page)


I thought there really hasn't been much to update here.


But, I also thought, oh yeah...Yep, there ARE things that can be updated!
So, here are a few important things to note:



1) While using the highest frequency / channel that supports your communications, is still a good rule....fact is, that with dwindling sunspot numbers the higher bands are already being used less, and with lower D-layer absorption, 8mhz is getting to be a daytime longer-range band, like 12mhz is (and 16mhz was/is)....so, while use of 8mhz for daytime long-range comms can still be limited, it is getting better and should continue to improve in the coming 2 - 3 years (and 12mhz and higher bands will become daytime-only and perhaps even unusable)



2) Secondly, there has been an ironic occurrence of sorts....

a) With the increase in inexpensive (and poorly-manufactured) electronic devices populating so many folks lives these days, where these devices add to the Receive RFI issues for users of HF Radio...
{Heck, even COSPAS-SARSAT has found increases in terrestrial 406mhz "background noise", especially in Asia and Europe....so the increase in HF / SW RFI in populated areas (like marinas, and even residential areas, etc.), is not surprising! }


b) Mother nature has cursed HF radio users with the lowest (worst) "11 year solar cycle", since 1906!! Our current Cycle 24 actually "peaked" in early 2014, after it's first peak in 2012.
And, it looks like the nominal "11 year" cycle, this time around might be more like 12 - 13 years, or so...meaning we might have another 2 to 3 years of a down-slope, and levels not getting back to "average" until a couple years after that!


https://solarscience.msfc.nasa.gov/images/Cycle22Cycle23Cycle24big.gif

https://solarscience.msfc.nasa.gov/predict.shtml

Combining these two occurrences means that HF radio users need to be extra vigilant in routing out RFI....of course when at sea or in remote areas, this is fairly easy, as the RFI is generated on-board our own boats! Note that RFI on the lower freqs is sometimes harder to eliminate, but is doable...but many HF installs suffer from this unknowingly, as the natural band noise of these lower freqs masked the RFI, but with quitter bands and many using the lower freqs in the coming years, AND with the plethora of RFI generating crap on-board these days, on-board RFI will be more of an issue for some!!

Please be sure to have a look at all the previous info (especially the links in post #1) regarding RFI, as well as some more here.





3) And, with new websites and new servers....some links might not be completely useful...and some info has been moved/lost...

But, here is a good URL for the Sailmail Primer
https://sailmail.com/wp-content/uploads/2016/02/smprimer.htm

And, here is some Sailmail App Notes, etc., that are no longer linked-to, from the "Primer"...
http://saildocs.com/sailmail


For those with RFI issues, in addition to the links to RFI cures / references in post #1, have a look at this excellent paper by Jim Corenman, you know the guy that wrote the "AirMail" program and helped start Sailmail....(this mostly deals with transmit RFI and RF / Antenna Grounds):

http://siriuscyber.net/airmail//rfi.htm


Also, for those looking for "drive level settings" for radios other than those listed in Airlamil, etc...or troubleshooting of low-transmit speeds / poor connectivity...have a look here:
https://sailmail.com/troubleshooting-slow-transmit-speeds/

Quote:
If your sending speeds are consistently slow then there is something wrong on the transmit-side of your equipment– an incorrect setting, a problem with the radio itself, or perhaps a problem with the tuner or antenna. Check your equipment carefully, or find a qualified radio technician to help (and have him read this also). In order to send at optimum speed your needs to be transmitting full power (or some reasonable fraction) and the antenna must be working efficiently.
Start with the radio power-settings and make sure that your radio is set to hi-power mode, power-level “3” for an Icom-M710. (Note that these comments are general but include some specific details for the Icom M710, other radios will vary). One of the myths is that low-power works just as well, this is only true when the station is relatively close- and definitely NOT the case from the middle of the South Pacific.
Next check the tuner connections- make sure that the ground and antenna connections are clean and tight. It is a good practice to remove, clean, and reconnect these connections every year or so, and make sure they are protected from the weather. Also make sure that the wire from tuner to antenna is as short as possible and spaced away from other wiring and metal by at least 2-3″, do not strap this wire into a harness bundle or to the lower backstay for example.
Next check the tuner function: Most marine radio’s have a “TUNE” indicator which indicates when the tuner is active, and when it has properly tuned. For an M710 and M802 radios the “TUNE” indicator on the display will flash for a few seconds when first transmitting as the radio completes its auto-tune cycle, then “TUNE” will remain ON steady. If “TUNE” flashes and goes off then the tune-cycle failed, and the radio will be transmitting very inefficiently and only with a few watts. This is either a tuner problem, or a problem with the control-cable, or a corroded antenna or ground connection.
Next check the transmit power-output. Most radios have a power-output indicator, the M710 has a “bar-graph” of 8 segments. For a M710 the power-out indicator should indicate 7 bars on steadily when calling the station, with the 8th bar (above the “SQL” label) flickering). (You can initiate FSK-transmission with Airmail’s “Set-PTC Aplitude” control, under the Control menu on Terminal window).
If you have a battery monitor which shows DC amps used from the battery, then another good way to check transmit-power is to check the INCREASE in DC amps while transmitting (with battery-charger OFF). For an M710 or M802 this should be 8-14 amps, 100W radios will be a bit lower. For example, if the battery-monitor shows 5 amps when listening, then it should show about 15 amps (a 10-amp increase) when the radio is transmitting.
If the transmit power is low, then this likely indicates that the “FSK” and “PSK” amplitude settings in Airmail are not correct for your radio. (These settings control the modem’s audio “volume” control for the signal sent to the radio, and this in turn controls the transmit-power. The FSK setting is used for calling, PSK once connected. PSK should always be about 30% higher than FSK).Open Airmail’s Tools/Options menu, connection tab, and check these settings in the lower-right. (You can also access these settings when Terminal-window is open, via Control/Set PTC amplitude menu). Older Icom M710’s are usually 140/170 for FSK/PSK, newer M710’s and M802’s are usually 250/330, systems which Marc Robinson set up usually have special cables and are set to 600/1000, Furuno radios are usually 1500/2000.
If increasing the FSK/PSK levels does not increase transmit power then the radio may be set to low-power mode (see above), or there may be a failure in the radio’s power-output transistors. You can verify the transmit function independently of the modem by finding an unused voice-frequency (e.g. 12,359.0) and whistling into the mic while watching the power-out indicator and/or battery-monitor. You should be able to reach full-power output no problem.



4) I also thought I'd post some direct links to relevant Video Playlists, that allow the viewer to watch videos in a logical order (skipping any duplicate or non-applicable videos, if needed).

{Please remember that these videos are not done in a lab or studio, nor by some "talking head" ....
Nope, these videos are done in the real-world, for real sailors....done on-board a real offshore cruising boat, LIVE, as it happens....no script, no BS...
Yes, these are LIVE, real-world, demonstrations of how/why all this stuff works....not some boring engineer talking "tech speak", nor some "spokesman" following a script...just me, my ~ 45 years of experience, and my M-802...
So, please understand that you're not getting high production values here, just the display and buttons of the M-802, and some of the Nav Station, WeFax machine, WeFax Charts, etc., along with real-world, live, unscripted narration (and some noises / voices from the radio, too), please be kind. }



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






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






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





"Offshore Weather" (sources and methods of obtaining good weather info, when offshore)
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2mPZAx2vWzdjTJjHlChruyY






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






"Offshore Sailing" (a couple of my Atlantic crossings) Just for fun!
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nbwAGh5DKgTCj15iyl6qoY







Now, I'm sure there is more that I could add, but please remember my intent here is use this thread as a reference / source, for those looking for info.....not to debate any specific issue (start a new thread for that)


If anyone else has some more reference info to share, please do so!

Fair winds.

John
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Old 08-08-2017, 15:54   #65
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

FYI, for those who don't have good internet access on-board, don't forget that you can download the videos from YouTube, store 'em on your computer, and play them whenever you need.

I'm usually not one to recommend software, but I've found "savefrom" to work great...
The fastest free YouTube Downloader

Fair winds.

John
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Old 08-08-2017, 18:15   #66
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Thank you, John!

(formerly N6VFJ - which I didn't know had expired. argh)
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Old 07-12-2017, 10:13   #67
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Re: Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, e

Thanks, your threads and posts are excellent kc1bkm
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