A rare guest: Murmansk meteo fax.


Yesterday and today I recevied a inverted weather fax on hf. The frequency is about 8444 khz (my YAESU FRG-100 is tuned to 8442kHz/USB). Internet says that this station is located in Murmask.

fldigi/RPi² demodulatin wefax from Murmansk

Picture inverted

This fax should be decoded in LSB mode. Then the picture could be in B/W instead of W/B :).

NDB beacons roundup

Another colour of my life as SWL is to get some nice signals of NDB beacons. NDB stands for 'non directional beacons'. See also Wikipedia for it.

This is what I get so far:

Since yesterday there are a few more on the list. But I had no time to list them on the map... So update's coming soon...

Another issue of Kyodo News in ufb quality ;)

Kyodo News issue 27th march, 2016.

An even nicer one ;).


Kyodo News decoded with Raspberry Pi ²


Today I recognised there's a fax transmission on 8.467 kHz. I looked into hffax.pdf and saw that the station transmitting is Kyodo News, Japan.

So I tested if Rasperry Pi ² can decode/demodulate the fax transmission. I installed fldigi. And voilá: it works fine!!!

Kyodo News, Japan on 8.467 kHz


And here's the big picture:

Kyodo New paper. I had too less lines in fldigi wefax setup :/.
Whole paper next time ;).

Nice one :).


My old World Space antenna


Today I'll reassemble my World Space antenna again. I hope that this antenna will work after reassembling.


Wondering where my videos are?


A few days ago Google deleted my Youtube account that I owned lot of years without any warning.

The truth is that I autouploaded some videos instead of upload them manually. It seems that Google don't want this kind of uploading a video or videos with python scripts.

So sorry guys. No videos inmo.


DMR with DSD on Bananapi?


On RTL-SDR addicted blog RTL-SDR.com I read about how to build DSD (Digital Speech Decoder Toolchain) on Linux. Therefore I tried to deocode DMR with this toolchain on Bananapi. The question that has to be answered was: has Bananapi enough power to receive DMR broadcasts and decode data stream with DSD same time? The answer is: almost.

Even if Bananapi has two CPU cores with about 1GHz something seems to be not right. As you can see Bananapi takes "only" 70% CPU on both cores. But the result of the decoded datastream exported as wav file is, uhm, very choppy.

I don't think that problem is power of the signal itself. It's about 20dB above noise.

To be continued...

Very first picture of Meteor M N°2


A few days ago I could get a decent broadcat of Meteor M N°2 satellite. Here's the result.

My very first picture of Meteor M N°2 digital transmission
Great Britain on the left. Baltic sea, golf of Riga, golf of Finland on the right.
My setup was Bananpi and R820T RTLSDR with toolchain by DH1MLJ, DIY QFH, TV SAT PREAMP. Always remember: this was the first test of the setup.

Even if this picture isn't as good as the ones in Satellitenwelt forum it's obvious that the picture qaulity is far better then the quality of the NOAA APT pictures.

NOAA APT analogue transmission


Waiting for Meteor M N°2. Ready to go image.


After I read about a ready to go Bananapi operation system image with Meteor M N°2 recording tools (scripts) on Satellitenwelt forum I'm trying to get a fine record of the satellite signal:

Bananapi is ready to record signals of Meteor M N°2

The image was created by om DH1MLJ. You can read more about it in this threat:


Thank you very much to the fine guys of Satellitenwelt Forum for sharing such an interesting information!

Good luck!


Bananapi and GQRX - works with low samplerate


Yesterday I found this interesting website from OP Michael, DG0OPK. It describes howto use Cubieboard and Bananapi for ham radio stuff:


The section "update: 6.December 2014" refers to Igor's website. Igor created a Bananapi image without any x server or something else. As you can read on Michael's page he writes down howto install x server and ham radio stuff.

Then I decided to install GQRX to test how it works on a 1GHz/1GB dual core embeded system. SDR is the well known RTLSDR R820T.

Here's the result:

GQRX on Bananapi

As you can see GQRX takes about 60% to 70% of CPU. You have to set samplerate to 250kS. All values above 250kS causes the CPU to use 100% of both cores :(.

But it's a beginning.