HF antenna AA20 replace or something different for weather fax?

[stav]

Morning Fine Folks,

As part of project 'going further afield (but not this year now). I was hoping to get weather fax up and running. Minimal cost is the issue, wanting to get old tech to work and if away for only a month at a time I don't want expensive subscriptions.

So I have a Lowe HF225 radio and a Tecsun Pl-600 so should be able to receive something. But the results have been disappointing with a bit of wire in the rigging.

I have on board a AAX5 but the antenna at the top of the mizzen mast does not have the stainless steel wire. A new one can be purchased for £100 ish but I could buy a NASA HF active antenna for £35ish.

Is the AAX5 worth spending the money on?

I will continue experimenting with pieces of wire.

I also once saw a piece of advice just showing some wire wrapped around a stay?

Any thoughts and advice welcome?

Thanks in advance.

 

[GHA]

Where are you trying to receive from? Bit of wire up the rigging or even croc clip onto a chainplate should get a decent signal without spending any money, though if you're in a marina or boatyard with other masts around then doubtful you'll get much. In an empty anchorage or out at sea it's a different thing altogether.
Which frequencies are you listening for? 10.1MhzUSB is DWB rtty which is usually pretty strong.

 

[stav]

Where are you trying to receive from? Bit of wire up the rigging or even croc clip onto a chainplate should get a decent signal without spending any money, though if you're in a marina or boatyard with other masts around then doubtful you'll get much. In an empty anchorage or out at sea it's a different thing altogether.
Which frequencies are you listening for? 10.1MhzUSB is DWB rtty which is usually pretty strong.

Hi GHA, been trying on my drying berth in the harbour and at home. Have tried a range of frequencies. Will try some more and seems a good excuse to go out and find a bay to anchor in. If I am allowed to do that!

 

[William_H]

One of the problems of our time is digital devices. They can produce a lot of interference which might make you think the antenna is no good. Really any piece of wire should be as good as any other. In practice the longer the better. So firstly try turning off everything except the radio. You may find things work much better. Turn items on one at a time to find the culprit. I have a security video recorder here in my office which obliterates all radio reception. LED lights USB power converters and computers of course can give noise.
One solution is to use a shielded cable from the radio to the antenna. This means the antenna only picks up from that outside remote place. However there ar eproblems in using shielded (coax) cable because it shows quite a high capacitance in what is a very high impedance circuit. This will detune the input circuit of the radio and simply bypass to earth much of the signal. Old car radios used to use a very low capacitance shielded cable to avert these problems but then they were typically only 2 metres long.
An antenna made for job may contain an amplifier at the antenna (mast top or at least outside) so increasing signal strength before it comes inside to the noisy environment.
Don't know if all this helps at all. good luck ol'will

 

[GHA]

Hi GHA, been trying on my drying berth in the harbour and at home. Have tried a range of frequencies. Will try some more and seems a good excuse to go out and find a bay to anchor in. If I am allowed to do that!

Some useful receivers online as well to have a listen from a usually good installation >
websdr.org
The top one, university of twente is a good one.
Again, 10.1Mhz is usually a good benchmark to check signalk strength. Android do an rtty app which will decode it.
And the world wfax schedule if you don't have it already >
https://www.weather.gov/media/marine/rfax.pdf
Happy listening

 

[stav]

Thanks, william_H insight like that always helps and GHA, will have a look.

I have had a couple of very grainy weather fax come through and I was very excited!