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Old 27-07-2014, 00:55   #16
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Re: Weather Freqs

Uh, thank you...
Quote:
Originally Posted by socaldmax View Post
Once again, another well researched, amazingly helpful post!!
But, there was no "research" done!! (this all from my own personal experience / memory, from 40 years of doing this and keeping up with things....and a few "bookmarks" in my web browser...)

Also, neelie and socaldmax, these posts you guys are commenting on, are from March, 4 1/2 months ago...and, I suspect Ralph, the original poster, found that his radio did not receive any "Single Side Band" signals (no BFO), and never came back here....


Fair winds, my friends...

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Old 27-07-2014, 01:48   #17
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Re: Weather Freqs

Canibul,
I wanted to add these short but important pieces of info for you...but, now I cannot go back and edit my post....so here they are...


a) If you're thinking this is a difficult process you're going thru...please remember we all started somewhere at sometime....and learning about HF radio is like everything else in life, just before you "get it", it seems daunting, but it's not....it just requires learning. like everything else in life!!
(oh, and remember there is wide world out there beyond Cruiser's Forum...



b) If you think the signals are weak, understand that many of the stations that some of us are trying to talk with (other boats) and/or listen to, are quite low powered in relation to many other HF radio users/operators...

As examples...
--Most other pleasure craft / your fellow sailors (and "Cruiser's Nets") use 100 - 150 watts, and some have fair-poor antenna systems....

--Chris Parker is limited to 150 watts transmit power...and uses low-gain (or no-gain) antennas...and he is 100+ miles inland, not on the water...

--Most commercial ships use 250 - 1000 watts, with very good antenna systems....

--WLO uses 1000 - 5000 watts....using directional/gain antennas, covering the oceans...
--NMN (and the rest of the USCG HF stations) use 4000 watts....with some directional gain antennas, covering the oceans....

--Many ham operators use as much as 1500 watts, some with large directional gain antennas...(although there are many hams that use < 100 watts...)

--Most aircraft HF transmitters are from 100 - 400 watts...and are all in the clear at altitude...
--Most HF aviation ground stations are 1000 - 5000 watts...with excellent antenna systems....

--AM radio broadcast stations use from 1000 to 50,000 watts, with excellent antenna systems....(most of the larger stations are 50,000watts...)

--BBC, VOA, and other shortwave broadcasts stations typically use 250,000 to 500,000 watts...almost all using very high-gain antennas....(and some use as much as 2,000,000 watts)

So, in addition to the variables of the ionosphere / radio wave propagation, local man-made noise, etc. there are wide differences between the transmitter power and antennas used by the various users of HF radio....

(and you can see why/how small portable shortwave radios work great for BBC, VOA, etc. in remote parts of the world, but some have difficulty using them the first times they try on-board, trying to listen to low-powered signals!!)


I hope these little points help explain things...
Fair winds..

John
s/v Annie Laurie
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Old 27-07-2014, 05:58   #18
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Re: Weather Frequencies

thank you, John. Your suggestion to listen to NMN instead of NMO made a world of difference. They are both roughly 1000 miles from here, but the Chesapeake broadcast came in fine while, as you know, I was having zero luck tuning in anything from New Orleans on voice. The synthesized voice on WLO also comes in fine. It was a question of having the right freqs to look for.

FWIW, while following your suggestions (!) I found that moving the radio outside did help a little as far as signal-to-noise ratios, but it wasn't a deciding factor. The 7m wire antenna also helped, but the reception was still acceptable with just the little telescoping whip. I did find that using the attenuation control on the Sony helped, too. That seemed to knock down noise a bit, which helped in voice reception clarity in this case. In fact, once I had a voice signal to play with in the first place, the rest of it was easy. I had the radio set up right, and was tuning it right. This is keyboard tuning, not rocket surgery. BUT It's difficult to fine tune a radio when all you hear is static. Fine tuned static, to be sure, but static nonetheless.

As for the MMSI stuff, hey, just because I don't always agree with someone's opinions doesn't mean I don't value and consider them. Where US government is concerned, I tend to question everything. And I do mean everything. I know it's annoying. My sister is the same way, and she annoys me. I think it's my mother's fault. She raised us to question authority. Can I sue? Seems to be the rage these days. But in the meantime, I will likely continue to question everything, and continue to resist the increasing efforts of some facets of the US government to monitor our every breath just because they can. I suspect I have a little more experience with that end of things than most on this forum.

You'll be glad to know that one of the new VHF radios on board does have our MMSI number programmed in. The SH 2200 GX with AIS/GPS will now diligently report my location to the US Government. When it's on. The other two VHFs on board do not, as far as I know. I continue to consider my physical location none of their business until I need for them to have it. They're supposed to work FOR us, remember? When did we decide it was just fine for them to start giving us orders?

Thanks again for the help. This radio is meant to hopefully work as our weather backup when we're too far from Wi-Fi and cell tower reception. Until the day when I find myself somewhere with a radio tech who can fix my iCom SSB xcvr. Such an animal apparently doesn't exist here. Maybe we'll take the boat to Fajardo next winter and try to get it fixed there.

My next move with the little Sony is trying to get weather fax data from it to an iPad or PC.
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Old 27-07-2014, 10:53   #19
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Re: Weather Frequencies

Okay, after that education by John, I've just spent a big part of a lazy Sunday morning here trying to figure this out. I was able to pick up Chesapeake NMN fairly easily. One frequency early today, with better results by moving to a higher frequency as the day wore on.

We bought an app (HF Fax by Black Cat systems) and I got my new Sony ready, with a nice little amplified speaker setup standing by in case I needed it, and we tried to get a weather fax from New Orleans, NMO. There was a scheduled transmission at 15:30Z or 11:30 here. I tuned the Sony to 12788 kHz, and picked up faint voice. Not the fax tones I was expecting. For the next half an hour, I tried everything I could think of. I tried getting back to the WLO I had heard earlier, but it was very faint and unusable. Anyhow, I was looking for just the fax, m'am.

I changed to the NMN HF voice freq 13089 and got the same exact voice that I was hearing, supposedly from New Orleans at 12788. so 12788 and 13089 kHz were a simultaneous broadcast. Okay. Well, where did the weather fax broadcast go?

My puzzlement continued at the end of the broadcast, while I was still tuned to 12788, New Orleans, right? But the voice signed off identifying the station as NMN, which is Chesapeake. So I was listening to Chesapeake voice on a New Orleans assigned frequency, and neither one of them was weather fax.

So, would one of you experienced radio/SSB gurus please tell me what I did wrong....THIS time?
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Old 27-07-2014, 11:50   #20
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Re: Weather Frequencies

Canibul,
1) I think you may have an old schedule???
Quote:
Originally Posted by Canibul View Post
We bought an app (HF Fax by Black Cat systems) and I got my new Sony ready, with a nice little amplified speaker setup standing by in case I needed it, and we tried to get a weather fax from New Orleans, NMO. There was a scheduled transmission at 15:30Z or 11:30 here.
As there is NO wefax transmission scheduled at 1530z, from NMG....
New Orleans Radiofax Schedule with Links
You see there are no NMG wefax transmissions scheduled between 1445z and 1800z (which allows them to use these transmitters for their Voice broadcasts)...

{BTW, NMO is NOT in New Orleans and does NOT use these freqs to send wefax!!!
NMO is the VOICE transmitter callsign of the USCG station in Honolulu....and KVM70, is the WeFax transmitter callsign of the USCG station in Honolulu....perhaps you are looking at the wrong schedules and freqs???}



2) Once you get used to HF radiowave propagation, it is very easy to "know" what freqs to use over what path, at various times, conditions, etc...(hence my "disclaimer" in my videos that they are not a substitute for a working knowledge of how things work, but rather are just a guide to help..)
Quote:
Originally Posted by Canibul View Post
I tuned the Sony to 12788 kHz, and picked up faint voice. Not the fax tones I was expecting. For the next half an hour, I tried everything I could think of. I tried getting back to the WLO I had heard earlier, but it was very faint and unusable. Anyhow, I was looking for just the fax, m'am.
Schedules for USCG WeFax transmissions are here...
Marine Radiofax charts

Specifically...

For the N. Atl....(NMF, Boston)
Boston Radiofax Schedule with Links

For Gulf of Mex, Caribbean, Trop N. Atl, and SE Pac...
New Orleans Radiofax Schedule with Links








3) As you can see on the NWS marine weather websites (and USCG sites as well), the USCG has two "Area Master Stations" (one on the Atlantic and one on the Pacific), and their other stations are "remotely keyed" from these Area Master Stations...
Quote:
Originally Posted by Canibul View Post
I changed to the NMN HF voice freq 13089 and got the same exact voice that I was hearing, supposedly from New Orleans at 12788. so 12788 and 13089 kHz were a simultaneous broadcast.

My puzzlement continued at the end of the broadcast, while I was still tuned to 12788, New Orleans, right? But the voice signed off identifying the station as NMN, which is Chesapeake. So I was listening to Chesapeake voice on a New Orleans assigned frequency, and neither one of them was weather fax.
They are supposed to be identical/simultaneous voice broadcasts, coming from two different transmission sites, with different antennas, pointing in different directions (hence one of the reason you hear one better than the other)...
There is NOT any scheduled wefax broadcast at that time from NMG....

(BTW, if you listen closely on some of the USCG freqs, you can also here NMC, Pt. Reyes Calif....transmitting out across the Pacific, using the SAME freqs as NMN....starting an hour after the NMN transmissions....
USCG HF Voice
Sometimes the NMN Offshore weather broadcasts run long enough that NMC transmissions start while NMN is still transmitting....and they will typically NOT interfere, as both their geographic separation AND antennas' directivity reduce/eliminate most of any cross-interference...)





4) Canibul, as you see there is NO wefax broadcast scheduled from NMG at that time....and if you watch the videos and read thru the links, etc. you'll soon be getting all the weather info/forecasts you need...
Quote:
Originally Posted by Canibul View Post
Okay. Well, where did the weather fax broadcast go?

So, would one of you experienced radio/SSB gurus please tell me what I did wrong....THIS time?



BTW, as you are starting to see, there are few things that prepare you for HF radio....no matter how many years in SOSUS you have, HF radiowave are different...
(For years, one of my brothers did SOSUS work in the Navy....Cape Hatteras and Grand Turk...at least that's what I've pieced together over the years, as he had a "Top Secret" clearance and has never confirmed anything at all...and although later worked as senior engineer at Motorola w/ their Iridium project, etc. he has NO knowledge at all of HF radio....so, don't worry, it'll come!!)



Fair winds...

John
s/v Annie Laurie
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Old 27-07-2014, 12:36   #21
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Re: Weather Frequencies

Captain John (ka4wja),

May I ask you to contact me off line at address below for some separate radio information?

Thank you.
Michael Barrett

michaelbarrett12@att.net
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Old 27-07-2014, 12:54   #22
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Re: Weather Frequencies

Canibul, I've been having pretty good luck with receiving HF wefaxes from local stations (Pt Reyes, CA; Honolulu, HI; AK, even as far as New Zealand) by using JVcomm32 and a 3.5mm male to 3.5mm male cable. I connect the line out of the radio (E1) to the mic in of the laptop and let it decode.

That particular software does a great job of keeping the image straight and auto detecting start/stop as well as page alignment.

Anything you can do to increase S/N ratio will make a big difference in image quality. I'm still in the goofing around phase (don't really need wefax) so I have all of the west coast/Pacific rim frequencies programmed into the radio. I don't have the broadcast schedule memorized or programmed in, so I just fire up the radio and scan through the memory to see if any of them are broadcasting. Remember, different frequencies work better/worse at different times of day/night.

Good luck!
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Old 28-07-2014, 07:19   #23
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Re: Weather Frequencies

Thanks, John. I was out again this morning, outside of the house, with the external antenna extended to 7 meters, trying to use the little tuning program that came with the HF Fax software. I used the schedule you listed,for New Orleans (NMO was a typo on my part, I was tuned to NMG and the same frequencies) and I tried at all the scheduled listings for 1200 through 1305Z. They're listed as re-transmissions, but in any case it was hopeless. I couldn't tune any of the three frequencies (4316, 8502, or 12788) that this radio accepts. They list another one, 17146.4 but my radio won't accept that many digits so I couldn't try 17146.4-1.9= 17144.5 kHz. I'm not even going to ask why they don't just list the frequencies one would tune a radio to. I'm sure there was a reason.

In any case, I listened to examples of what I should hear. It's pretty standard modem sounding stuff we've all heard before. But damned if I can get any of that out of this setup, after three mornings of trying everything suggested.

This is the kind of stuff someone shipwrecked or stuck in a marina for weeks could continue to mess around with, but I cannot imagine doing this at sea. So far, my $ 300+ Sony 7600 experiment is a bit disappointing. My thinking is now that the money would have been better spent on a sat phone, where I could call someone who had access to a weather forecast.

Thanks for all the help.
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Old 28-07-2014, 09:45   #24
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Re: Weather Frequencies

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Originally Posted by Canibul View Post
., but I cannot imagine doing this at sea.
At sea it's actually quite simple, with nothing near but flat water reception is normally excellent, hardest thing is to remember to turn the refrigerator back on afterwards (nasty things for RF interference.)
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Old 28-07-2014, 10:05   #25
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Re: Weather Freqs

Quote:
Originally Posted by Canibul View Post
I just yesterday received a new Sony ICF-sW7600GR. I tried for a couple hours to find something useful on SW or SSB yesterday, but the only things I could hear was when I punched in the numbers for the local FM disc jockey. Received that okay.

I bought the World Radio TV Handbook with the Sony, but so far I haven't figured out what all that stuff is. So I got on the internet and found a listing of Caribbean Weather net channels this morning. I figured out I am an hour behind AST, and I tried the listed frequencies at 06:30, 07:00, and 08:00 AST etc. I tried to find Chris Parker, and I tried to tune in to the Coconut Telegraph net. But So far, I have yet to hear a human voice on SW or SSB. same static, which I can run up and down in freq with the USB/LSB switch and fine tuning pot.

After reading this thread, I tried imputting 10000 and 15000 to see if I got some kind of time signal, but all I heard was the same static.
I've read the brief manual, and messed around with all the buttons and switches and their descriptions all make perfect sense to me. yet....so far nothing a five dollar transistor radio wouldn't have done.

So far, I've been using the telescoping antenna and have not strung out the wire one. I'm on a bluff sixty feet above the Caicos Bank in a house surrounded by glass sliders and no nearby buildings. Shouldn't I pick up something?

I must be doing something wrong. These freqs are in kilohertz, right?
I find the SW receivers to be next to useless. Our onboard SSB and Ham sets have auto tuners, a good ground plane and backstay antennas. There is lots of voice, weatherfax and Morse traffic.

Even our ham unit with the antenna disconnected picks up Morse.

The DSP internals of the dedicated transceivers are significantly more sensitive and have much better SN capabilities than cheap receivers. You get what you pay for with comms.

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Old 28-07-2014, 10:49   #26
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Re: Weather Frequencies

Well, that's making sense. It is a cheap radio, at $130 from Amazon. To try out that Sony cost me about $335, with transportation, customs duty, clearance fees.
As mentioned, we do have an iCom 700 or 701 ( I forget) professionally installed on the boat, but I suspect it was damaged by a lightning strike. It's presently disconnected from power. It has a backstay antenna, and an iCom antenna tuner. I've been trying to decide whether to leave it on the boat or get rid of it. I'm trying to declutter this boat from the detrius that three previous owners thought should be on board over the previous three decades. We have never gotten anything useful from the SSB, and I tried with it quite a bit for the first few weeks we had the boat, as we came down the ICW from Jax to Lake Worth. I tried again in the Bahamas.

I bought this Sony 7600 to see, for sure, if SSB would be useful to me on the boat. If so, then I would start looking for a way to get ours repaired. But so far, 100% of my experience with SSB has indicated that it's kind of like a mechanical wristwatch from the 1950's. It worked then, and it work's now, and it's useful and has a world of fans and hobbyists but meanwhile there are other options that didn't exist back when it was the only game in town.

Now I'm thinking more that for someone like me, who is obviously too stupid to work a transistor radio after a 40 year technical offshore career and two pilots licenses, that a sat phone makes a lot more sense. . I'm just looking for the most bang for the buck as I continue to rehab and rebuild this old boat. I'm asking similar questions about wind generators, solar panel types, etc. It's part of a massive self education program.

I did pick up USCG HF voice yesterday on the Sony, so that's the results I have to go by. I could barely make out what the voice was saying, sitting on a very quiet patio sixty feet above the ocean. Add the noise of a storm at sea and two diesels blaring, and even that would have been hopeless. A weatherfax would be good, but that doesn't seem to be in the cards for me to see how good it could be.
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Old 28-07-2014, 10:55   #27
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Re: Weather Frequencies

Canibul,
Sorry you're having troubles...
(I wasn't near the radio this morning to check, but I assume NMG was transmitting okay....they usually are booming in here on 8mhz and 12mhz daytime...)

I think I see what some of your problem is....and will attempt to briefly clarify things...

First off, I think you're "over thinking" / "over complicating" things....
Slow down, and follow the steps / links, and things will easily work...


Quote:
Originally Posted by Canibul View Post
Thanks, John. I was out again this morning, outside of the house, with the external antenna extended to 7 meters, trying to use the little tuning program that came with the HF Fax software. I used the schedule you listed,for New Orleans (NMO was a typo on my part, I was tuned to NMG and the same frequencies) and I tried at all the scheduled listings for 1200 through 1305Z. They're listed as re-transmissions, but in any case it was hopeless. I couldn't tune any of the three frequencies (4316, 8502, or 12788) that this radio accepts. They list another one, 17146.4 but my radio won't accept that many digits so I couldn't try 17146.4-1.9= 17144.5 kHz. I'm not even going to ask why they don't just list the frequencies one would tune a radio to. I'm sure there was a reason.
This looks like your main problem....as they are listing the frequencies correctly, but you seem to be mistuning them...
Do NOT subtract 1.9khz from the 8502, or from 12788....
USE 8502khz...(that's 8503.9 - 1.9), and USE 12788 (that's 12789.9 - 1.9)....
{understand that 1200z thru 1300z is usually going to be too early for 17mhz, and certainly for the relatively short range of 1200 miles....you're more likely to use 12mhz...)

Instead of me posting a link for you to read, perhaps it's better if I just write the procedure here, or even better I'll quote directly from the NWS Marine Weather USCG WEFAX Page???

Quote:
See tables below for abbreviated versions of radiofax broadcast schedules. Assigned frequencies shown, for carrier frequency subtract 1.9 kHz. Typically dedicated radiofax receivers use assigned frequencies, while receivers or transceivers, connected to external recorders or PC's, are operated in the upper sideband (USB) mode using carrier frequencies.
New Orleans (NMG) 4317.9, 8503.9, 12789.9, 17146.4(1200-2045z) kHz Radiofax Broadcast
Start Broadcast0000Z0600Z1200Z1800ZBroadcast Schedule2025Z


Quote:
NEW ORLEANS, LOUISIANA, U.S.A.

CALL SIGN FREQUENCIES TIMES (UTC) EMISSION POWER
NMG 4317.9 kHz ALL BROADCAST TIMES F3C 4 KW
8503.9 kHz ALL BROADCAST TIMES F3C 4 KW
12789.9 kHz ALL BROADCAST TIMES F3C 4 KW
17146.4 kHz 1200-2045 F3C 4KW





In any case, I listened to examples of what I should hear. It's pretty standard modem sounding stuff we've all heard before.
I'm not sure what examples you've listened to, but HF WeFax does NOT sound like "standard modem sounding stuff"....
I suspect that this, combined with your tuning being off by almost 2khz (1.9khz), are the two proximate causes (after listening at the wrong times the previous two days) to why you haven't gotten WeFax reception...


But damned if I can get any of that out of this setup, after three mornings of trying everything suggested.
The other 2 mornings you were listening at the wrong times for wefax and this morning on the wrong frequency....

(Please excuse me for being blunt, but all this in is in the links provided...)




This is the kind of stuff someone shipwrecked or stuck in a marina for weeks could continue to mess around with, but I cannot imagine doing this at sea.
If you read the links, have the correct time, use/follow the correct schedule, use the right frequency at the right time-of-day, etc. IT DOES WORK....and most find no issues with this set-up/procedure....
(unfortunately you started with bad info, wrong schedules, wrong freqs, etc...)


So far, my $ 300+ Sony 7600 experiment is a bit disappointing.
Not sure how much the shipping to T & C is, but you can buy the 7600 on-line for just a bit more than $100....and my Sangean 909 cost me $120 all-in shipped to me...and the "antenna" is just a scrap piece of wire (free)....
And JVcomm was a free download (still need to get around to putting it on my new laptop, though)
So, this can be done for far less than $300...


My thinking is now that the money would have been better spent on a sat phone, where I could call someone who had access to a weather forecast.
While all the above info I wrote was factual....here I'm going to give you an opinion....(please forgive my bluntness)

In my opinion, you went into this without actually educating yourself on exactly what to do nor how-to do it....and found it frustrating....
You further exasperated the situation by not reading / following the correct freqs/times/schedules, and by not precisely following the information/instructions provided (mainly in the links provided)...

So, while you may think (your opinion) that "this crap doesn't work", etc....looking at it from my side, I think (my opinion) that you simply jumped into something without bothering to learn about it, assuming that you could figure it out, and didn't follow the procedures/instructions, and now just want the easy way out....

And I DO understand your point of view....and I don't blame you at all for feeling that way....(unfortunately many folks feel the same way when frustrated by some "new-to-them" technology)

But, if you would indulge me one last comment/suggestion:
READ everything here, FOLLOW the procedures / schedules / times / freqs, and learn how HF signals and radiowave propagation, and you'll be better off than 90% of the cruisers out there....

And, understand that "sat phones" are NOT as reliable as you may think....and in crarppy weather, you'd find yourself trying to make a call hanging on for dear life in the cockpit, drenched in sea water and wondering why in the hell you didn't follow John's advice (you do realize that a handheld sat phone will NOT work below decks...and trying to balance a laptop in the cockpit at the same time...well good luck with that!!)



Thanks for all the help.

You're VERY welcome....and while I know that my opinion might be taken as rude or insensitive, understand that I DID answer your questions politely and completely, before bothering you with my opinion...


Fair winds...

John
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Old 28-07-2014, 11:15   #28
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Re: Weather Freqs

This is an unfortunate occurrence.....
Quote:
Originally Posted by leftbrainstuff View Post
I find the SW receivers to be next to useless.

The DSP internals of the dedicated transceivers are significantly more sensitive and have much better SN capabilities than cheap receivers. You get what you pay for with comms.
I'm sorry but the "sensitivity" of these receivers is NOT any worse than most ham / marine HF radios...
This is just completely UNTRUE!!
(there may be some very slight differences, but these are FAR outweighed by the atmospheric noise!!)
This is a topic that I have significant experience/expertise on (40 years), both professionally in my electronics/communications business and as a ham/marine radio operator....

Yes, the S/N might be better with your full-featured commercial marine and ham radios installed, but this is NOT the small SW radio's fault...
It is the added noise that they are subjected to, and typically a lower signal level due to some folks trying to use (compare) their built-in telescopic antennas (compared to their backstays)...

Yes, you do get what you pay for...
But, a small portable radio CAN work very well for the purpose of receiving offshore weather forecasts (Voice or WeFax)....
Although most users, will use them almost exclusively for Voice weather forecasts, as the added complexity of trying to use the small portable unit, with an ext. antenna wired some how where there is little noise pick-up, and then trying to couple that to a laptop/tablet, etc. for wefax reception, etc. becomes VERY cumbersome and complicated to use...(and most will use this as just a "back-up" means of weather info, NOT their primary means...)

I have never touted this as a primary means, and never will...
And, I have scrupulously mentioned how necessary it is to LEARN how HF radio works, before attempting to use HF radio systems, and this is especially true when trying to use a small portable radio, etc. (certainly a compromise system)!!!


The main issue/problem is that most do not understand the issues of:
a) How to use the radio (most marine HF radios are significantly easier to use, hence increased frustration from those attempting to use a small, portable radio....already HF radio is an unfamiliar neighborhood, and few bother to learn their way around!)

b) radiowave propagation...

c) the negative contribution of on-board RFI, where most that install full-featured commercial marine radios or ham radios actually take the time to reduce on-board RFI, and/or take the time to understand what RFI is and howto deal with it.... (and to a minor case, SOME of the commercial marine radios and SOME of better ham radios handle these noises better....but this is a small part of the solution...)

"Post Hoc, Ergo Propter Hoc"....does NOT work here in this situation...
There are variables that come up and are solved (not the least of which is operator education), with full-featured marine radio installs that are NOT even known about, let alone solved by many of those trying to use portable radios...
Think of the saying that "all poodles are dogs, but all dogs are not poodles"....


To be clear my $1800 M-802, along with it's $500 tuner, copper strap/Dynaplate ground system, long backstay antenna, etc. DOES work much better than my $120 Sangean 909....
But the difference is mainly in HOW you use/operate the radio (and in what you're using it for), NOT in the actual raw receiver sensitivity and performance...
Yes, the M-802 is MUCH easier to use and sounds much nicer....but as long as I know what freqs to tune to at what time-of-day, and have a decent wire antenna strung up for the Sangean, it DOES work, and it DOES receive both HF Voice weather and HF WeFax just fine....(both at the dock in Florida, throughout the Bahamas and Caribbean, and YES across the Atlantic to EU...), but the Sangean is a pain in the ass to use....so, it is of course my back-up, just as it is for many offshore sailors....


Sorry, gotta' go...
More later, if needed...

John
s/v Annie Laurie
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Old 28-07-2014, 11:51   #29
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Re: Weather Frequencies

I haven't given up. Obviously you're reading something that I have yet to learn.

Frequencies.
The instructions seem to say that USB receivers connected to PCs for Weather fax use the upper side band USB using carrier frequencies.

And right above that it says that "for carrier frequency, subtract 1.9 kilohertz"

So, I took that publlished frequency of, for example, 12789.9 and, as instructed, subtracted 1.9 kilohertz to get the carrier frequency. That leaves me with 12788 kilohertz. This is what I was listening to. While listening at 12788, I tweaked it up and down 1 kHz in each direction and went through a very very slow fine tuning process, stop to stop. Today I was watching the freq. analysis tuner with HF Fax software. I was trying to find some way of matching up two peaks at those two freqs corresponding to ones and zeros for black and white printing purposes. I understand this.
So, how can you say I was off two kHz? I couldn't use the published freq as is, anyhow. Is 12788 not the carrier it's talking about for the published freq of 12789.9?

This seems to be what I am completely getting wrong, correct?
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Old 28-07-2014, 13:03   #30
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Re: Weather Frequencies

Okay, we're doing good!!
But, I cannot speak intelligently about any of your software configs / issues....as I am not familiar with it....
(I use a separate, stand-alone, dedicated wefax receiver, a Furuno FAX-408, as my primary wefax system......and my M-802 as secondary feeding a laptop with JvComm software....and my Sangean as a back-up receiver...)

How you get you software to work???
Well that's up to tech support / instruction manual from the software supplier....

If you can hear the screeching of a wefax signal, but cannot get the chart on the computer, then the issue is either computer or software related, NOT radio or antenna related!!!
(remember you DID receive the NWS/NOAA Offshore Voice Weather from the USCG's NMN, just the other day....so the radio and antenna DOES work!!!)




As for the Radio / Antenna (RF) end....that's my bailiwick!!!
And, this is where I CAN help!!!

For clarity, don't worry too much about the whys/how this afternoon, let's just get 'er done....

You will use 12788 (and 8502 and 17144.5)....



I'm on-board, sitting at my Nav Station, right now as I type this....and my Furuno FAX-408 is printing out perfectly clear wefax'es from NMG's 12mhz transmitter....and I'm tied to the dock with one of my neighbor's marine refrigeration units causing me some received RFI, but still have perfectly clear wefax'es!!!
{My Furuno FAX-408 uses my aft lower shroud as its antenna, fed with a short length of RG-8x coax....it's about 22' of slightly sloping vertical...and works great, nothing special about it....just like a 20' -25' long piece of wire, no tuners, no nothing....(and this is also my HF-DSC receive antenna for my M-802, just using a coaxial "T" to split the coaxial antenna feedline to both the FAX-408 and the DSC receive antenna jack on my M-802...}

See these photos, to see what my Nav Station looks like...(they are all different photos, ven though the links show up here as the same...)
Nav Station
Nav Station
Nav Station

Nav Station


(From my location in S. Florida, right now at 1815z thru 1900z (2:15pm - 3:00pm EDT/AST), both 8mhz and 12mhz signals from NMG are strong....and 17mhz is weak but usable, as I'm closer to New Orleans than you are.....and I suspect that you will have 12mhz and 17mhz strong and 8mhz very weak / non-existent, at this time of day...)

The RFI / Noises that I'm getting from my neighbor's boat, on 8mhz are enough to place some static / slight grey noise on top of the weather chart, but it is still clear and useable, but I've switched back to 12mhz and everything is crystal clear, just like I picked up the chart off the table at the National Weather Service Office!!!




{If you care to know, my M-802 is also receiving NMG's wefax signals on 12, 8, and 17mhz (12 is best, followed by 8, and 17mhz is a bit weak, but usable...)
But the tuning is different than the FAX-408...the M-802 is tuned to 12788.0 (just like your receiver should be), the FAX-408 is on 12789.9....
They are both 'tuned" correctly, and both receive the SAME signals....it's just the variations in how a "dedicated wefax receiver" (what the wefax transmitters are designed to transmit to) tunes/displays the frequency and how other radios tune/display the freq!!!
It is really a bit to-do, over nothing....a distinction without a difference!!}


As for my Sangean....
Batteries are dead and corroded, and my good batteries at up at the house (350' of dock and 39 stairs away..)
But, I'm gonna' try some old ones out of a dim flashlight...
No go....Sangean is dead....sorry....(probably my neglect, letting it sit with corroded batteries!! But, in my own defense, I've been stuck at the dock for a while now....if heading offshore, I'd buy anew radio....actually think I'll look on-line tonight...

But, last time I tried it (a year and a half ago), it DID work okay....
(and besides I don't have getfax or jvcomm on this new laptop yet. so I couldn't download a chart to the computer anyway..



So, to sum:
You will use 12788 (and 8502 and 17144.5)....

And, you should have excellent signals today!!


EDIT:::
It's now just 1905z, and I've just printed out the last hour of wefax charts from NMG....the west and east halves of the Topical Surface Analysis, 48 hr wave period forecast, current sea state analysis (wave height and direction), 24 hr surface forecast....
And, all are perfectly clear....and 48 hr surface is currently printing out....
All is good...
And, I expect this to continue for the next hour, or so...


Second EDIT:::
And, now at 1912z - 1914z, I just checked into the MMSN on 14300khz (ham radio net), while still receiving / printing out the 48 hr surface forecast...and no major issues, just a bit of "noise/static" on the weather chart, from when I was transmitting on the M-802, which is understandable, being their antennas are just a few feet away from each other, and there is only about 1.5mhz separation....
The reason I mention this is, because the chart is still VERY useable....perfectly clear, except for some noise/greying on top in s few small lines, when I was transmitting on 14mhz....so, the HF wefax transmissions are very robust....just a real-world FYI (sometimes the anecdotal info is actually believed more than my "factual info"...


fair winds..

John
s/v Annie Laurie
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