SW HF and SSB Radio

scruff said:
Following - we got caught out in arsceid mor this summer. No phone reception nor vhf weather info in anchorage. "Supposed" to round Rubna Hunish heading sound down the minch in 15kts. Got 40kts.

Was wondering if weather fax to laptop would provide better overview and prevent being caught out again. In fact I recently missed a cheap nasa SSB receiver on ebay
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Blatant plug but I am about to sell 2 nasa ssb receivers. Pm me on here and I'll reply with my contact details.
 
OK. I remember there being two but had forgotten what the second was.

W.

Roberto said:
There are two Navtex frequencies (theoretically three but the third in HF is not used), 518 and 490kHz, the first is "international" in English, the second in local languages, though in the UK it is used for Inshore Waters.
FWIW, I would not waste time trying to decode Navtex with a portable general receiver, apart from wishing to experiment: the transmissions are very short, one has barely the time to adjust settings and it's already over, all the radio/pc stuff should be left "ON" the whole day... imho one of those situations where a dedicated receiver is way way better.
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dolabriform said:
I've been playing around with a RTL-SDR Dongle, Cubic SDR and FLDGI on my mac to try and get weatherfax with pretty much no success

Although I'm in East London, I would have thought I would pickup northwood ok? I suspect it's down to the ariel supplied with the dongle, although it pickups up FM radio ok.

Has anyone had any success with this?
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Northwood is not currently transmitting. Hamburg should be good and strong though
 
Bilgediver said:
Have you tried tuning to 4608 USB . If nothing is heard then leave it there for at least 20 minutes. This is the frequency for Northwood weather fax. I can pick it up most of the daytime here but maybe if you are down in the home counties it could be difficult. This can be resolved on a computer using the Seatty Software in as mentioned and linked in the first of my mails here in page 1 of the thread. For further information on weather fax stations then the USA published frequency list for ships is as below.

If you load Seatty into your computer you may need help to get started however a PM to myself or post here should bring help.
The UK fax station times are on the last page of the publication but many more to try for.

Don't give up if all you get is a black page.. Well soon have you receiving something. I have run Seatty on everything from Win 3.1 to windows 10

Noaa Fax Directory.

https://www.weather.gov/media/marine/rfax.pdf
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Interesting, I had no idea Northwood was back on. Apologies for the misleading reply I made earlier on this thread.
 
simonafloat said:
Interesting, I had no idea Northwood was back on. Apologies for the misleading reply I made earlier on this thread.
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Northwood transmitting this morning but it isn't reliable, might be there but sometimes disappears for a while.
http://websdr.ewi.utwente.nl:8901/
TmRQ5km.jpg
 
Ship'sCat said:
During this lockdown away from my boat I have bought a secondhand Roberts FM MW LW SW radio with SSB. This was just to fiddle around and ponder whether this - or something like it - might be a useful thing to have in a boat. Perhaps for obtaining weather faxes using black cat software on a mobile adjacent perhaps, or just for listening in while in distant places. I find the radio works but rarely can I pick up anything at all on any of the SW options. At the same time I notice that threads on this subject are a few years old and I wonder if SW is going extinct as I understand stations have been closing? Does anyone have any frequency for a weather fax station I can try to pick up through SSB from here in the north of England, just out of curiosity?
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Hamburg should be the best signal, it broadcasts on 3 different frequencies. Have a look online for the schedule and frequencies. Ssb, usb mode. If you've got it tuned correctly it will sound like an old fashioned fax line. I use hf fax, an ipad app. Just place the ipad mic near the radio speaker. It's completely automatic and starts to listen as soon as you launch it. As the map starts to appear on screen, tweak the fine tuning until the contrast of the map is acceptable. The biggest issue is household interference - if you can, run the radio off batteries, same if you have a laptop or tablet. Even better, turn your leccy off at the mains. Best of all, take all your gear and drive somewhere as far from buildings as possible. Ssb basically works terribly onshore but the further offshore you go the better it gets.
 
Roberto said:
There are two Navtex frequencies (theoretically three but the third in HF is not used), 518 and 490kHz, the first is "international" in English, the second in local languages, though in the UK it is used for Inshore Waters.
FWIW, I would not waste time trying to decode Navtex with a portable general receiver, apart from wishing to experiment: the transmissions are very short, one has barely the time to adjust settings and it's already over, all the radio/pc stuff should be left "ON" the whole day... imho one of those situations where a dedicated receiver is way way better.
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One advantage of the Sony SSB receivers is that they are stable so I have memory buttons marked for Navtex A and B and the times of the broadcasts are published. I decode it with either software or a Ham TNC PK 232 which works well so just switch on when a transmission is due and the file can be saved or printed. Fine at home but not convenient on a small yacht.
 
I've just bought a Nasa SSB unit and have been playing around. Firstly why did no one mention the sound? Blimey it's ear splitting and horrendous!

Secondly, the weatherfax's I'm getting are reasonable from home (1970's suburb on outskirts of Small / Medium city) but still quite a lot of noise (isobars 75% show but characters illegible). This is in standard house with wifi / central heating / fridges etc running.

How far from electrical appliances do we have to go to get a clear reception? I have a 12v battery at home. I could simulate a powercut at the main fuse board and run off battery power. The nearest house is circa 10m away. Is this enough distance to make a discernible difference?

Or do I load the stuff into the car and drive to a lay by 20miles away and set everything up there?

This is all quite interesting and fun though!
 
scruff said:
I've just bought a Nasa SSB unit and have been playing around. Firstly why did no one mention the sound? Blimey it's ear splitting and horrendous!

Secondly, the weatherfax's I'm getting are reasonable from home (1970's suburb on outskirts of Small / Medium city) but still quite a lot of noise (isobars 75% show but characters illegible). This is in standard house with wifi / central heating / fridges etc running.

How far from electrical appliances do we have to go to get a clear reception? I have a 12v battery at home. I could simulate a powercut at the main fuse board and run off battery power. The nearest house is circa 10m away. Is this enough distance to make a discernible difference?

Or do I load the stuff into the car and drive to a lay by 20miles away and set everything up there?

This is all quite interesting and fun though!
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You'll notice an improvement if you kill all electric in the house but external sources like streetlights and neighbours devices will still cause issues. Yep, drive somewhere remote and chuck the antenna wire up a tree and earth to the ground with a copper pipe. Basically shortwave is better the further offshore you are! Once you've got the hang of it then consider a line out cable from the radio to an input on your tablet /pc. If any of you have a nasa unit without a line out I can advise on adding one.
 
Ship'sCat said:
During this lockdown away from my boat I have bought a secondhand Roberts FM MW LW SW radio with SSB. This was just to fiddle around and ponder whether this - or something like it - might be a useful thing to have in a boat. Perhaps for obtaining weather faxes using black cat software on a mobile adjacent perhaps, or just for listening in while in distant places. I find the radio works but rarely can I pick up anything at all on any of the SW options. At the same time I notice that threads on this subject are a few years old and I wonder if SW is going extinct as I understand stations have been closing? Does anyone have any frequency for a weather fax station I can try to pick up through SSB from here in the north of England, just out of curiosity?
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I found (it was a while ago I used mine) that reception at home or even in marinas was pretty sketchy, mostly I believe due to interference from other sources like street lighting, flourescent tubes, car's, motor's such as fridges but once you were 5 or 10 miles away from these sources it cleaned up alot. I used a nasa and laptop on atlantic trips and also listened in to nets where we knew their times and frequencies. I found it a very good tool, we didn't have sat phones or smart phones.
 
scruff said:
I've just bought a Nasa SSB unit and have been playing around. Firstly why did no one mention the sound? Blimey it's ear splitting and horrendous!

Secondly, the weatherfax's I'm getting are reasonable from home (1970's suburb on outskirts of Small / Medium city) but still quite a lot of noise (isobars 75% show but characters illegible). This is in standard house with wifi / central heating / fridges etc running.

How far from electrical appliances do we have to go to get a clear reception? I have a 12v battery at home. I could simulate a powercut at the main fuse board and run off battery power. The nearest house is circa 10m away. Is this enough distance to make a discernible difference?

Or do I load the stuff into the car and drive to a lay by 20miles away and set everything up there?

This is all quite interesting and fun though!
Click to expand...


Yes it is a bit noisy so normally turn it down to a whisper. Sometimes you can clean up the image by fine tuning and some radios are better than others in being able to do this.

You could have a problem with local interference which is problem I have. I deal with this by clipping ferrite sleeves on the audio leads to the laptop. The received signal can be improved by the use of a long wire antenna.

I don't have a problem with radio interference on the fax signals here in Edinburgh but fading is a problem at certain times of the day but usually the 4610 khz signal is good for much of the day with 8040 khz at a better signal at certain times.

Note that the frequency shown in publications is slightly higher than the indication on your dial.
 
Skylark said:
Would a band pass filter help scruff with domestic reception of his NASA receiver?

Just picked this at random, first hit on Google

1.5-30MHz 100w Band Pass filter BPF for Reduce shortwave interference Ham Radio | eBay

I have one somewhere in my loft that I used many years ago to stop me from causing transmission interference to my neighbours.
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One version of the nasa unit (hf3/w) had a built in bypass filter that outputted via a dedicated serial output to a sound card. It worked very well, unfortunately only with one software package that was DOS only!

Newer ones have a normal line out for your sound card. Tbh the modern software packages will be listening to and filtering the scruffy signal as part of their processing.
 
So I've been playing about...

Earlier I had the ssb radio (12v) hooked up to the mains via a transformer for an old 12v modem. The line out ssb / into laptop wasn't picking up anything, despite the cable working fine in the car so it was being listened to by the tablet's microphone. Fairly poor results.

Swapped out the aux cable for a brand new one and fiddled about with sound card settings - this one works and much clearer picture.

Then powered the ssb from a 12v leisure battery, destined for the skip. Much, much better.

Powered off the house via main fuse board, little appreciable benefit.

I'm now picking up faxes from Hamburg which are perfectly usable and 'cos its via a aux cable its not ear spliting. Its practically magic!
 
As with Scruff I too have picked up some weatherfaxes today from Hamburg. This was on my Robert's R-9914 portable with my android phone with Wolphi software placed nearby. I can just about pick out some numerals on the isobars. The location was upstairs in a terraced house in a city location.
I really appreciate this thread, everybody. There has been no end of useful and interesting posts.
 
When I had a ham station in the UK I used to pick up ‘numbers stations’ - just groups of four numbers.

At the time no one seems to know what they were for. I wonder if now they’re still there or if anyone knows their purpose?

W
 
PilotWolf said:
When I had a ham station in the UK I used to pick up ‘numbers stations’ - just groups of four numbers.

At the time no one seems to know what they were for. I wonder if now they’re still there or if anyone knows their purpose?
W
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I meant to click "quote".

Number stations are widely believed to be used to communicate coded messages giving instructions or other information to embassies and spies.
They still exist, as do spooks, and some people still listen to them. It must be a bit like train spotting, a complete wast of life time.
 
That was the belief then too. So nothings changed!

W

Lucy52 said:
I meant to click "quote".

Number stations are widely believed to be used to communicate coded messages giving instructions or other information to embassies and spies.
They still exist, as do spooks, and some people still listen to them. It must be a bit like train spotting, a complete wast of life time.
Click to expand...
 
PilotWolf said:
When I had a ham station in the UK I used to pick up ‘numbers stations’ - just groups of four numbers.

At the time no one seems to know what they were for. I wonder if now they’re still there or if anyone knows their purpose?

W
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I also understood that many we for propagation tests as well as time references prior to GPS. Not always as sinister as always thought.
 
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