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Old 31-10-2016, 23:38   #16
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Re: SSB Watch keeping while at sea

Quote:
Originally Posted by ka4wja View Post
Well, even after contacting Cruiser's Forum admin, I was prevented from correcting a typo above, and was unable to get them to correct it either...
Since this could be a serious problem, putting life and safety at risk, I thought corrective editing would be appropriate, but CF admin thinks otherwise...so...

So, please note my typo and correction!
The correct freq is 8291.0khz....

Sorry about the typo!

Fair winds...

John
John -- any time someone posts an ssb question I always wait for your reply as you are the master of the ssb and always very enlightening and I always learn something new -- thanks -
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Old 01-11-2016, 01:03   #17
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Re: SSB Watch keeping while at sea

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Originally Posted by chuckr View Post
John -- any time someone posts an ssb question I always wait for your reply as you are the master of the ssb and always very enlightening and I always learn something new -- thanks -
What he said...

Thanks so much for your informative posts. I have benefitted greatly from your technical knowledge and willingness to share.

Steve
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Old 01-11-2016, 10:39   #18
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Re: SSB Watch keeping while at sea

Gordon West wrote an interesting SSB booklet back in the 90's. It was geared toward ICOM users and owners, but still has plenty of great information. There is a section that talks about take off angle, frequency, and range with different ionospheric conditions. Propagation changes constantly and the easiest way to find out where the MUF (Maximum Usable Frequency) is would be to just scan around and listen.

Hams use beacons to find out where the propagation is going and can easily find out where the MUF will be. That's the best place to operate on HF as it will give you the greatest distance. However, SSB in marine applications is different since you might not be looking for the greatest distance. You may be trying to reach a specific distance. That's where Gordon's short booklet shines. It gives a realistic idea of distances based on time of day and position. The information seems to be compiled using measurements taken over a very long time. It also talks about using the marine operators to get real time measurements.

Here is the link

I found it informative and although slightly dated packed with useful SSB marine information.
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Old 01-11-2016, 12:05   #19
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Re: SSB Watch keeping while at sea

John, give us a chance please. Anyway now updated.

Pete

Quote:
Originally Posted by ka4wja View Post
Well, even after contacting Cruiser's Forum admin, I was prevented from correcting a typo above, and was unable to get them to correct it either...
Since this could be a serious problem, putting life and safety at risk, I thought corrective editing would be appropriate, but CF admin thinks otherwise...so...

So, please note my typo and correction!
The correct freq is 8291.0khz....

Sorry about the typo!

Fair winds...

John
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Old 01-11-2016, 15:06   #20
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Re: SSB Watch keeping while at sea

1) Chuck and Steve,
Thanks for the compliments!
You're all very welcome!
And, I know I have a tendency to ramble on and give too much detail...so it's nice to know that sometimes the detail is appreciated...
Quote:
Originally Posted by chuckr View Post
John -- any time someone posts an ssb question I always wait for your reply as you are the master of the ssb and always very enlightening and I always learn something new -- thanks -
Quote:
Originally Posted by steve77 View Post
What he said...
Thanks so much for your informative posts. I have benefitted greatly from your technical knowledge and willingness to share.
Steve






EDIT:
As I read this posting....I'm struck that it might come off as negative or antagonistic??
I hope not!!
This is not my intent, not at all!!




2) Now, I don't want to drift the thread around...nor come off like a know-it-all jerk...
And, yes Gordo has done a wonderful service to sailors, regarding radio comms....as has Icom themselves (except for their manuals!), as well as SGC...
The booklet you reference was (according to Icom reps, back in 2003) written mostly by Icom engineering staff, the intro was from Gordo...
And, yes....it is a good reference...BUT...

But, Seeking Solace, there are some things you write that might confuse some....not the least of which is to reference an old booklet, rather than more up-to-date info...
NOT saying the booklet is bad, just saying there are more up-to-date references...

Yes, radio waves still travel the same way they have for 100 years, but since the booklet was put out by about Icom 20 years ago (before they had an MF/HF-DSC radio...and before the full implementation of the GMDSS and HF-DSC services and equipment), there are things that are different now!
(and, this also applies to the wonderful CCA radio comms papers, and unfortunately many of these older references are still being used by the "sailing press / media", rally organizers, and even the ISAF!)
The one "non-government" / "non-official" reference that is the exception is Sailmail!!
Sailmail is a very good tech reference, and they keep things up-to-date!!

This is one reason why I'm hesitant to recommend "booklets", "pamphlets", etc....but rather reference the IMO / ITU, GMDSS Master Plan, USCG, AMSA, NZMA, etc...
Not that the "rules-of-thumb" provided in the booklets are all bad, but rather that some/many of them are out-dated, and it's hard to tell someone to "read this, but don't worry about this part, or that section, etc."

But, a specific reason....and a VERY important reason....is the old booklets / old information is VERY out-of-date in regards to Distress signaling and specifically the use of "2182"....
NOBODY (with exception of New Zealand and possibly Bermuda Radio) monitors 2182khz any more!! And, with the exception of the USCG, nobody has been doing a Voice SSB radio watch monitoring 2182 for a LONG time!!!
Since the full implementation of the GMDSS in Jan 1999, nobody has been required to maintain a watch on 2182....
And, please understand that even for a decade or more before that (since the 1980's), almost all ships (SOLAS-grade) and most shore stations, used "2182 Watch Receivers", which were silent and listened only for the "two-tone alarm" from another ship's radio....and the shore stations and bridge crews/radio officers were only required to listen to 2182khz during the two 3-minute long "quiet periods" each hour, at the top and bottom of the hour...
So, for all practical purposes, for most "cruiser's" and "recreational sailors" (unless equipped with a "GMDSS version" of a marine HF-SSB radio), and until an affordable MF/HF-DSC-SSB Radiotelephone (such as the Icom M-802) was released, VHF radio was the only way to raise another vessel at sea, since the 1980's!
And, except for USCG, AMSA, NZMA....as well as AT&T Hi-Seas, Shipcom, Portishead Radio, etc. and the other "Public Coast Stations" around the world, whose channel/freq you would need to know, there wasn't a clear and concise, and RELIABLE way to raise a coast station either!!
(Which is one of the reasons why the GMDSS was put together, in the early 1990's, by the IMO/ITU, thru the SOLAS conventions!!!)

{Fyi, while the USCG still did try to monitor 2182, up until 2013, they were discouraging its use for about 20 years....and when the cost to improve/repair their 2mhz equipment was beyond being cost effective, they commissioned an involved study in 2008-2010, and found no real use of their 2mhz/MF systems, and the decision was made to forgo any repair/upgrade to their 2mhz/MF systems and they announced a phase-out plan.....they ceased 2mhz/HF operations (in 2013)....and the US, just like Australia and a few other nations, ceased to have a Sea Area A2...Only Sea Area A1, A3, and A4....}

This is just one example why I'm very hesitant to recommend any of the older references....and understand that unlike others, I'm NOT selling anything!
I have no books to sell you, no services to tell you about, no equipment to peddle, etc....all of the info I provide is FREE and is all easily tracked back to official sources (SOLAS, GMDSS, USCG, AMSA, NZMA, etc. even Sailmail is not only an excellent tech reference, but they do keep things up-to-date!!! and sometimes even Icom gets it right! )
The internet is a great source and resource, but since there is SO much, it can be a bit overwhelming, as well as lead many to old / out-date info, and/or even worse, to blatantly false and erroneous info....not to mention the marketing hype for certain products/services!!


3) Now, as for communications ranges on various frequency bands...well, this is not only something I've studied extensively for over 40 years now, but have taught classes / seminars on...
And, the real issue here is:
How to explain a complicated subject both, in layperson's terms, and in enough detail to understand, but not too much to confuse!
(which I hope I did above, and in the above referenced threads and videos)
And, depending on who is writing it, and their audience (and their mood ), the exact numbers and guidance can vary...heck, mother nature varies things even more, so no worries...

The main gist of what I've tried to stress about freq/channel choice is:
a) Use the highest freq that will sustain the communications, for the distance to be covered and time-of-day...
b) Choose your freq based on YOUR need / desire (as described in "a"), and NOT based on "what everyone else done for years...(doesn't mean that "everyone else" is wrong, just that they may not be right, and you should learn/know that...)
c) Understand that will the plethora of consumer electronics and their chargers, as well as all the "digital" devices and microprocessors on our boats these days, and all the crap on everyone else's boats, etc....the receive noise levels can be quite high, if you don't do something to reduce / eliminate this RFI....(and this can be worse on the lower bands)
This increase in RFI was something not even anticipated 20 years ago, and has become a rather intrusive problem in the last 5 years!




4) I could ramble on and on....but, don't want to over-whelm....
But, I'd like to leave you with one important fact of life, it is "physics" / "mother nature" that controls how HF radiowaves travel...not us, not our antennas, not our grounding systems, not our radios, not our modems, etc. etc. etc...
The "take-off-angle" of our signals thru the ionosphere / the angle that our signals are reflected at, is set by the ionosphere....not by us!!!
While we have vertical antennas over sea water, giving us a extremely low pseudo-Brewster angle, and assuming we have some sort of RF ground / Antenna ground, we will have a fairly low angle of peak radiation (aka "take-off angle"), but understand that it is the ionosphere that determines what angle the signals will be reflected at, NOT us!!
So, quibbling over antennas / ground systems / etc., is all about efficiency and effectiveness.....and it is all a matter-of-degree!!!
(heck, a wire coat-hanger stuck in the back of the radio could have a low take-off angle.....but doesn't mean it's a good antenna choice!




5) Seeking Solace, some specific comments here, in red....
Quote:
Originally Posted by Seeking Solace View Post
Gordon West wrote an interesting SSB booklet back in the 90's. It was geared toward ICOM users and owners, but still has plenty of great information. There is a section that talks about take off angle, frequency, and range with different ionospheric conditions. Propagation changes constantly and the easiest way to find out where the MUF (Maximum Usable Frequency) is would be to just scan around and listen.
For the casual HF radio user, and/or the typical ham, "scanning around, and listening" is okay....not optimal, mind you....as the band might be "open", but few (or nobody) on-the-air....

But, for those looking for a specific freq/band to use for a certain range of distances, to either monitor / stand-watch on, and/or run a net on, knowing about radiowave propagation is an almost necessity!!!

And, for those with little, to no, knowledge of radiowave propagation, there is maritime HF-DSC (a quasi-ALE system) that will allow you to message another vessel and/or lots of other vessels, either anywhere or in a specific region (NAVAREA), without worrying much about propagation as the radio will try to establish contact and alert you when you've received an acknowledgement....and if not, you can try a different band...

I do not wish to seem rude, in any way....but, I think assuming that some layperson sailor would be "scanning around" trying to find their buddies / fellow cruisers on-the-air, on some band/freq, at some unknown time, etc. is misunderstanding the situation here...



Hams use beacons to find out where the propagation is going and can easily find out where the MUF will be.
Some hams may use beacons, but most seasoned hams use current solar indices and their expertise to determine daily radiowave propagation probabilities....
It is the understanding of radiowave propagation and the experience and expertise here that I try to relate to others in a concise way....it's difficult to do, due to both the many variables and to rapid changes, both of which can make predictions sporadic at times...

But, if you understand the theory and cultivate the experience, you CAN know what is happening and what will happen on-the-air ahead of time, to a fair certainty....and all the beacon network can tell you is what is available now...



That's the best place to operate on HF as it will give you the greatest distance.
Actually, it's not....
There are many, many variables here.....but for optimal use over low-angle, single or multi-hop paths, the best place to operate is as close to the "OTF" (Optimal Traffic Frequency), which is typically about 90% of the MUF....

And, for regional communications distances, of 50/100 out-to 300/400/500 miles, this is where high-angle paths work....Near Vertical Incidence Skywave (NVIS), where you will be operating significantly below the MUF....typically at 33% of the MUF....
But, the deciding factor here is the "Critical Frequency", the freq above which no signals will be reflected back from a zenith angle....meaning this is the maximum freq for NVIS paths....and of course this varies from hour-to-hour, as well as variations due to time-of-year and position of the 11-yr solar cycle...


However, SSB in marine applications is different since you might not be looking for the greatest distance. You may be trying to reach a specific distance.
Yes, this is correct....


That's where Gordon's short booklet shines. It gives a realistic idea of distances based on time of day and position.
The ranges he gives for "ground wave" over sea water are a bit over-estimated! (yes, to powerful shore stations, this is possible, but not for cruising boat to cruising boat!!)
And, "groundwave" range above 8mhz is significantly less!!!!!
And, to the contrary "skywave" is used on the lower bands, all the time....even daylight hours....this is how all comms on the lower bands take place when beyond 50-100 miles!!
(this is a widely misunderstood fact...heck, even many seasoned hams think their antenna and/or antenna height sets the angle that their signals are reflected at!!! And, many still do not understand the use of Near Vertical Incidence Skywave...)
Yes, over sea water (using vertical antennas) "groudwave" is very usable....just not at the distances stated...

And, getting cruising boat-to-cruising boat range as the tables show is impossible on some of the bands, but on others it is significantly UNDER-estimated!!
Except for early morning and/or near sunset, you're not going to reliably get these long of range on 6mhz and 8mhz....but, conversely, you can reliably get significantly longer ranges on 12mhz and 16mhz daytime!!

And, every contact that is beyond 2000 miles, day or night, low-band or higher-band, is a multi-hop path.....(as example US East Coast to Europe is a two-hop or three-hop path....and from my boat in Florida to Australia, where I regularly receive their 12mhz weather broadcasts, and late a night even their 8mhz/8176khz weather, is a long 5-hop or 6-hop path...)

Just saying there are some things there that are better left out of a discussion like this!
And, I haven't even touched on "the counterpoise"...

The information seems to be compiled using measurements taken over a very long time.
Actually it's a retread of the same tables and charts that have been around since 1970/71....when Maritime HF SSB was coming into its own, with many hundreds of powerful SSB Voice coast stations....I first saw these figures in 1973....
Nothing wrong with taking in the basic info and theory, just be aware that some of the specific info is generous and a bit dated!!


It also talks about using the marine operators to get real time measurements.
And, while here in the US this is still a possibility...using Shipcom WLO/KLB (and the NWS/NOAA Weather broadcasts from the USCG), the rest of the world isn't so lucky anymore....
Here is the link

I found it informative and although slightly dated packed with useful SSB marine information.
There's lots more (like erroneously calling 2187.5khz an SSB Distress freq!)....but, I gotta' go...

I wish to reiterate that I don't think the booklet is bad, just that some of the info is very out-of-date and some info is a bit misleading....there are more up-to-date references and more practical info available...so, why recommend something inferior??

Fair winds...

John
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Old 01-11-2016, 15:38   #21
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Re: SSB Watch keeping while at sea

John,

Thanks for adding in lots of the many technical things I left out, mostly because it wasn't relevant to the discussion. I'd have to agree with the vast majority of what you said. It's radio theory, certainly not fact after all.

It's great that you had a lot of other references to add that were much more current. I read that booklet back when it was produced and really only meant to reference some of the charts. I'll try to be more specific in the future. I'll be checking out some of the new information you listed even for my own personal knowledge.

I guess I'm spoiled being a ham and would be far more likely to be rag chewing with distant stations than to be calling other vessels. That's a lot more fun, but far less utilitarian given the application.

I'm sure the OP and others who visit this thread will be able to discern what is the latest information by reading it all. There is a wealth of knowledge that can be found out there and sadly a lot of it is out of date.

Hope your TR7 is still doing great. I know I miss my TR4C and remote VFO, but after working with my FT-847 I can't say I miss all those extra steps before pounding some brass. Maybe I'll catch you on a short path HF someday. My call is KG4KGW.
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Old 01-11-2016, 15:51   #22
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Re: SSB Watch keeping while at sea

I might add that whenever possible we maintain a watch on 14.300USB. There are well run nets including the Maritime Mobile Service Network operating on that frequency around the clock. We have adequate battery and charging capacity to permit a 24hr watch on both VHF and HF. For those who wish to maintain an HF watch I can recommend the Yaesu 817; a wonderful QRP transceiver that uses less than 500mw on receive and can be powered by AA batteries. It has a GREAT receiver and is small enough to be a great back up radio.
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Old 01-11-2016, 16:23   #23
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Re: SSB Watch keeping while at sea

Brian,
No worries!
I've been in a bit of a frustrated mood the last few days and afraid that is coming out thru the keyboard in a unpredicted way!
Quote:
Originally Posted by Seeking Solace View Post
I'll try to be more specific in the future. I'll be checking out some of the new information you listed even for my own personal knowledge.
No need to be "more specific", that's why there's fanatics like me....to spend hours writing out mundane details that few care about...
(this week it takes my mind off family medical issues!)





I'm with 'ya 100% here!
Quote:
Originally Posted by Seeking Solace View Post
I guess I'm spoiled being a ham and would be far more likely to be rag chewing with distant stations than to be calling other vessels. That's a lot more fun, but far less utilitarian given the application.




Yep, they're working FB...
Love the TR-7!
I've actually got two of 'em! (one I bought new, almost 39 years ago....the other was a "no receive" $300 bargain, that I bought about 15 - 20 years ago...and repaired in 30 seconds!)
Quote:
Originally Posted by Seeking Solace View Post
Hope your TR7 is still doing great. I know I miss my TR4C and remote VFO, but after working with my FT-847 I can't say I miss all those extra steps before pounding some brass. Maybe I'll catch you on a short path HF someday. My call is KG4KGW.




And, Scott....I like the Intercon / MMSN / Pac SF nets as well!
Usually leave the M-802 in 14.300 when on-board, doing boat chores, etc...
Quote:
Originally Posted by Scott Berg View Post
I might add that whenever possible we maintain a watch on 14.300USB. There are well run nets including the Maritime Mobile Service Network operating on that frequency around the clock. We have adequate battery and charging capacity to permit a 24hr watch on both VHF and HF.



73,
John
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