Receiving Radio Weather Fax

May 5, 2017
30
Catalina C36 mkII PA
I want to use my Sony SW7600GR as a receiver to get a weather fax to my iPad. I have HF Weather Fax decoder app for iPad already installed and all seems to be working. The only problem is receiving a clear transmission so I can get readable weather map. Just wondering if anybody is using a similar setup and how you get clear transmission.
External antenna maybe? If so, what kind? Just a long wire. Any ideas are greatly appreciated.
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
First off, if you haven't already done so, make sure you are receiving the signal using Upper Side Band (USB). If your radio has the ability to use filters you would want to set them for narrow, around 2.5 KHz I believe. An external antenna will definitely help. You can tie a bit of wire to a spare halyard and run it up the top of the mast. Make sure you tie another thin rope to the halyard in case you lose the antenna.

Some hints about HF radio. In the morning the frequencies to listen to would be in the lower band. 5-8 MHz. In the afternoon you can go up to 12-20 MHz. As the sun starts to set, you will go back down in frequency. To help determine how the bands are doing, check the signals from WWV/WWVH (note: male voice is Colorado, female voice is Hawaii) on 5, 10,15,20, and 25 MHz. These are all in the AM band.

This is an older document but might help you understand time vs frequency. http://www.nws.noaa.gov/os/marine/rfax.pdf

Try those and see if you can get better reception.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
I have the same radio. Bought it about 3 years ago in Annapolis for the same reason you did.
I was told it was the best radio, best quality. Paid the premium price vs others.
I could never get anything on it other than standard am/fm.
I looked on the Internet for frequencies and times, used the book that came with the radio, hit up chat sites. Nothing.
I heard one or two faint broadcasts of low budget programming once.
Had the same luck when moved back to CA, although I did momentarily pick up an SSB scheduled meet from Mexico once.
Never heard any weather faxes.
I even used the supplied plug-in external antenna, although I think it's not for shortwave. You have to buy a different and expensive one.

The radio is excellent quality, physically and the sound is very good when the station is clear, especially in FM.
Reception beats my onboard stereo, so I use the Sony in the cockpit for AM talk shows.
 
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May 5, 2017
30
Catalina C36 mkII PA
Yesterday I run some tests with long wire (~80ft) in my backyard and that is what I was able to get.
First is a cloud cover for Mexican Bay and Caribbean, second one is direction and wave height for the same area.
I think it is not too bad for getting this reception in Calgary residential area and receiving a signal from New Orlean. It was still a daylight and apparently at night is better reception at higher frequencies. Any comments or suggestions to improve this?
IMG_1856.JPGIMG_1857.JPG
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
You are limited to the receivers sensitivity. I don't think that radio was really designed to work with those types of signals. Usually those are for broadcast AM and FM. Making the antenna longer does help but only to a certain extent. The wire is not matched to the antenna input on the radio. Attaching the wire to the whip antenna will net the same results. If you are really serious about this project then you might want to invest in a communications receiver like an Alinco DX-R8.Yes they are expensive but the Sony does not compare to the larger receivers.

You might be able to add a shortwave antenna tuner. That will help match the antenna to the antenna input impedance.

Now, let's fix that antenna of yours. You want to get it to the length that the antenna is resonant. Some might say it is a waste of time but I think any antenna that is "tuned" is better than a length of wire. So look at the frequency you are using. If this is the primary then use the formula 234/F(MHz) for a 1/4 wave antenna, or 468/F(MHz) or a half wave antenna. As an example...
234/13.2 = an antenna length of 17-3/4 feet. For the half wave just double, or 468/13.2 = an antenna length of 35-1/2 feet. This will at least get your antenna vibrating on the resonant frequency.

Lastly, if you are on the boat and your radio has a ground lug somewhere (or even make one), take a length of wire and attach a bolt to the wire. Throw the thing overboard, er... the wire with the bolt, not the radio. The bolt and wire should be submerged about 6 inches. This should help to eliminate some of the noise and it will act as part of the antenna also.

Lots to do, I know. Good luck!
 
May 5, 2017
30
Catalina C36 mkII PA
Thank you for antenna info. I will playa with that over the weekend. For now I use a gas line for the ground. I will try the bolt thing when I get on the water.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
I have to laugh that Skipper "never heard any faxes". I'd ask what exactly does a fax sound like? to the untrained ear it just sounds like static till the identification tones come on (top of the hour I believe) and then they just sound like tones. If you listen to your land fax you will get an idea. After the phone stops ringing there are some "i'm a fax machine, are you a fax machine, why yes I'm a fax machine too, lets fax" handshaking and then "that modem noise" The actual fax is that modem noise and on a radio sound A LOT like static. Can even be below the squelch level so turn the squelch off/all the way down.
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
You are limited to the receivers sensitivity. I don't think that radio was really designed to work with those types of signals. Usually those are for broadcast AM and FM. Making the antenna longer does help but only to a certain extent. The wire is not matched to the antenna input on the radio. Attaching the wire to the whip antenna will net the same results. If you are really serious about this project then you might want to invest in a communications receiver like an Alinco DX-R8.Yes they are expensive but the Sony does not compare to the larger receivers.

You might be able to add a shortwave antenna tuner. That will help match the antenna to the antenna input impedance.

Now, let's fix that antenna of yours. You want to get it to the length that the antenna is resonant. Some might say it is a waste of time but I think any antenna that is "tuned" is better than a length of wire. So look at the frequency you are using. If this is the primary then use the formula 234/F(MHz) for a 1/4 wave antenna, or 468/F(MHz) or a half wave antenna. As an example...
234/13.2 = an antenna length of 17-3/4 feet. For the half wave just double, or 468/13.2 = an antenna length of 35-1/2 feet. This will at least get your antenna vibrating on the resonant frequency.

Lastly, if you are on the boat and your radio has a ground lug somewhere (or even make one), take a length of wire and attach a bolt to the wire. Throw the thing overboard, er... the wire with the bolt, not the radio. The bolt and wire should be submerged about 6 inches. This should help to eliminate some of the noise and it will act as part of the antenna also.

Lots to do, I know. Good luck!
Brian, with all due respect, you hams are so particular with your quarter wave lengths and half wave lengths for antennas, not to mention loading coils and antenna tuners. Back in the day when people still listened to AM radio, a friend set up an "off shore" AM radio station. The antenna was an abandoned power line outside of his parent's house. He connected to the antenna with a treble hook attached to a wire that he tossed up to the abandoned line. The FCC boys were quite impressed with the operation, the clarity of the signal and the signal strength, not to mention the programming brought to you by Peyote Pete's Pot House.

Seriously, thank you and PZ for the info on receiving weather faxes on an iPad. Good information and something I've been meaning to pursue.

Dave, son of K2ROG (aka KH6DYX for a while)
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
I have to laugh that Skipper "never heard any faxes". I'd ask what exactly does a fax sound like? to the untrained ear it just sounds like static till the identification tones come on (top of the hour I believe) and then they just sound like tones. If you listen to your land fax you will get an idea. After the phone stops ringing there are some "i'm a fax machine, are you a fax machine, why yes I'm a fax machine too, lets fax" handshaking and then "that modem noise" The actual fax is that modem noise and on a radio sound A LOT like static. Can even be below the squelch level so turn the squelch off/all the way down.
You ask what a fax sounds like, then you describe what a fax sounds like.
Now that's funny.

I know what a fax sounds like.

As I said, I never heard any faxes.
Even though I was listening for them, on published frequencies, at scheduled times.
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
@pzmaria, I was just listening and printing the WEFAX broadcast from Pt. Reyes, California on 12786KHz assigned (12784.1 KHz dial) and even though the signal was loud, I still took hits. Even a few out of sync page hits. So unless you are right next to the transmitter, you will probably take hits.

I am sure you know this, but make sure you are on the correct frequency. There is the assigned frequency (the one printed in the WEFAX schedule from NOAA) and there is the dial frequency with is 1.9KHz lower that the assigned. It will make a difference.

This from the PDF...
"Unless otherwise stated, assigned frequencies are 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."
 
Apr 22, 2011
865
Hunter 27 Pecan Grove, Oriental, NC
Yesterday I run some tests with long wire (~80ft) in my backyard and that is what I was able to get.
First is a cloud cover for Mexican Bay and Caribbean, second one is direction and wave height for the same area.
I think it is not too bad for getting this reception in Calgary residential area and receiving a signal from New Orlean. It was still a daylight and apparently at night is better reception at higher frequencies. Any comments or suggestions to improve this?
View attachment 139338View attachment 139339
I have a similar but older model of your Sony receiver. Took it to the Bahamas a few years ago to catch ssb weather reports and load hf noaa weather faxes to my laptop. My faxes looked much like yours and I found it easy to read through some of the static driven lines. I used the long line roll-up antenna that came with the Sony. As it turned out, I found that Chris Parkers ssb weather net reports were far more useful than what I got from the weather faxes.
 
May 5, 2017
30
Catalina C36 mkII PA
I knew about this -1.9 kHz rule but appreciate reminding thou.
For now I'm working how to get directly with a hardwire to my iPad microphone to eliminate any extra sounds from outside.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Hey Skipper, did not mean my post as a dig. Lots of folks that get into digital HF get very frustrated because "it all sounds like static" the first time you hear it. After you mess around with it for a while you certainly can tell the different modulations (including fax) by ear.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
Hey Skipper, did not mean my post as a dig. Lots of folks that get into digital HF get very frustrated because "it all sounds like static" the first time you hear it. After you mess around with it for a while you certainly can tell the different modulations (including fax) by ear.
Yup.
 
May 5, 2017
30
Catalina C36 mkII PA
I found a way to go directly with a hardwire from the radio to my iPad microphone. Connecting thru 3.5mm male to 2x female stereo 4 pole splitter and regular 3 pole sound cable I was able to go directly to iPad microphone. That eliminates any outside sounds from the boat. For fine tuning I used nice feature that came with HF Weather Fax app. It's a visual tuning. You just have to tune to get strongest fax signal on two red lines. I found it is better and more precise than listenning to fax chirping.
s-l1600.jpg
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
@pzmaria, thanks for the update. Which station do you get your fax from? LA, MA, CA, AK, HI, or overseas/Canada?
 
May 8, 2011
189
ODay 25 Cambridge
Used the Sony SW7600GR with a Sangean ANT-60 portable shortwave reel antenna to receive weather fax (and broadcasts) in the Bahamas in the spring of 2016. Worked very well.
 
May 5, 2017
30
Catalina C36 mkII PA
Brian, at this time I'm in Calgary AB and was receiving faxes from New Orlean.