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Messages - MHZ

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Utility / Re: HF ACARS (ARINC)
« on: August 08, 2019, 2238 UTC »
I may have named this topic wrong, not sure. Is HFDL and HF-ACARS the same animal? This freq is for HFDL ARINC.

Utility / Re: HF ACARS (ARINC)
« on: August 06, 2019, 0603 UTC »
No, I was on the listed freq of 8927, I was just asking if you would do the same 1.9k shift as with WeFax.

Utility / Re: HF ACARS (ARINC)
« on: August 05, 2019, 2238 UTC »
Ok thanks.
With HF Acars is it the same as Weather Fax, 1.9 below carrier freq? Or are the listed freqs the correct ones to use?

Utility / Re: HF ACARS (ARINC)
« on: August 05, 2019, 2152 UTC »
Just listening now at 0747 Eastern Aust Time (2147z) and it is still there, a lot weaker than earlier on, now between S6 and S7.
In respect to decimation (which I must admit I am not fully aware of how it functions), up to 8 I can still hear it, above that it is gone.

I have uploaded a audio file below of what I am receiving. You can see that the data changes and towards the end there is a definite burst of data.


Utility / Re: HF ACARS (ARINC)
« on: August 05, 2019, 2137 UTC »
HFDL is very susceptible to a undesired tone on frequency, to the point of no decodes even for strong sigs.
Ok thanks for that tip, never done HFDL before yet.

It looks like you have a fairly strong signal that is not HFDL in the passband, but I could be wrong.
If you mean the signals up on 9350 and thereabouts, they were AM shortwave stations.

The sig in the pic you posted does not look like HFDL.
Possible! Although I have never heard anything before on 8927 here. As this was around 3/4AM here, there was nothing running that would have been causing the noise.
I keep a pretty close ear on 8-9 MHz as that is were most of the LDOC freqs lay for this area, which I listen to quite a lot. I will take a listen at different times through out today and see if it is present.

You don't need 10MHz of spectrum displayed to copy HFDL.
Not sure if this is a tip or a comment, I was only running 2 MHz at the time, which is typically what I run it at. Only deviate from that in the VHF aviation band, or when I am hunting stuff on VHF/UHF.

My RSP is set to use low IF and decimation 32 with a resultant spectrum width of 300KHz.

Yes, same here Low IF, although as you can see from the pic my dec was at 1, which is default, I will try your suggestion and see how it works, thanks. As for noise, I am fortunate enough to live in the country in a farming area, as such I have very little man-made noise to contend with. Only noise here is the TV inside when the old man watches it of a night-time and now and then the water pump - but both only effect certain freqs. I am confident once I relocate my long-wire the tv will no longer be a problem. I did have a dipole running off the house near where the tv is located and the noise was horrendous across all HF bands, rendered HF totally useless while it was on.

Oh and I forgot to mention the electric fence, it only effects MW and LW bands though, and is rather band on certain freqs in LW band, it favours 77.5 KHz unfortunately :(

WEFAX and SSTV / Re: WEFAX software?
« on: August 05, 2019, 1825 UTC »
Fldigi here myself.
I may take a look at Multi-PSK as well one day soon. But for now Fldigi works just fine, running Win7 here at the moment and SDRPlay RSP2/SDRUno.

Utility / HF ACARS (ARINC)
« on: August 05, 2019, 1822 UTC »
May not be in the right forum here, but it was the closest I could find.
I am taking a fair stab that this is out of Guam. Just seems to be to strong for San Francisco which is the only other TX location for 8927 in the lists I have found.

The question is:
Why is there nothing being decoded in the PC-HFDL software? The tone of the digital signal changes often, yet can see nothing being decoded at all on the screen. Completely blank as you can see below.
What am I doing wrong? I tried moving off the center freq +/- 2k with no success either.

WEFAX and SSTV / Re: VMW Wiluna
« on: August 01, 2019, 2326 UTC »
Those are very nice. Where's your QTH?

North of Warrnambool, Victoria. Australia.
In a very (electrically) quiet country location, all power lines are underground.

In all of these I still had not set the slant as you can see. But I have found even with the slant correction it doesn't always work super well.
The signals from both VMC/VMW vary a lot here, when they are good, they are good usually consistently S9 on the SDRUno meter. Being winter here there is a lot of noise and fading. There is a transmission at 0600z (from memory) which is beamed to Tasmania, it must be incredibly directional as I have never been able to hear it.

I am hoping over the summer months that I will be able to receive some of the Kyodo News faxes, can't read a scrap of Japanese, but it would be cool to receive/decode it.
Also being trying for faxes from Kodiak and the famous Berring Sea - but the low power and time of year is against me right now :)

WEFAX and SSTV / VMW Wiluna
« on: July 28, 2019, 0812 UTC »
All on 7533.1 KHz.
SDRPlay RSP2/SDRUno and Fdigi.

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