Weiter gibt es Ungereimtheiten beim seit einigen Jahren groß angekündigten Remote-Transceiver-Netz des DARC e.V., das seine Fördermitglieder schon mit jeder Menge Geld vorfinanziert haben. Offenbar wird es nur von zwei Personen getragen, wobei man für die komplette Software sogar auf ein Nicht-Mitglied des “Bundesverbandes für den Amateurfunkdienst” zurückgreifen musste – der somit einem Kreis entstammt, der das Netz nach dem Willen des Vorstandes nicht einmal wird nutzen dürfen …
Den Stand der Dinge habe ich nach öffentlich zugänglichen Informationen in der Juli-Ausgabe der Fachzeitschrift “Funktelegramm” zusammengefasst. DARC-Noch-Mitglied DL7AG hat diesen Text mit Erlaubnis von Joachim Kraft, Herausgeber und Chefredakteur des “Funktelegramm”, auf seine Website gestellt.
NEW: The Receivers’ Pane on top covers spectrum and spectrogram of up to six demodulators – look at different modes and bandwidths. Also new: “Signal History” at the bottom.
Simon Brown, G4ELI, has further developed his software SDR Console which has become THE platform for a real bunch of very different SDRs. The new public preview has two more exciting features:
- “Signal History” takes the signal strength of the given bandwidth each 50 milliseconds, which can be saved in a CSV file. It is also shown in three different speeds on a display.
- “Receivers’ Pane” shows up to six combos of spectrum/spectrogram of the complete up to 24 parallel demodulators (they additionally can be shown in the Matrix, as in former versions).
See screenshot on at the top.
“Signal History” offers many applications, to name just three:
- analyze fading and its structure with an unsurpassed time resolution of 50 ms
- document fade-in and fade out
- measure signal-to-noise ratio of signals
As an First Aid, I have written a PDF of 19 pages with 36 instructive Figures. There you find a step-by-step introduction plus numerous example on how to use this valuable tool in practice. Please download it here. (Another tab opens, where you have to double-click “SDR_COM_Marker” to start download.)
Surely, I will come back to these most welcomed features in more detail. For now only some screenshot examples regarding “Signal History”, which have been realized by analyzing the CSV files with QtiPlot:
With some statistics applied on the CSV file of Signal History, you’ll get a deep inisght into fading structures. Top: original data (black), averaged (yellow), median (read line). Bottom: box diagram, histogram, 3D-band. See following screenshots for some examples.
… and this is just the beginning! [Receiver: Elad FDM-S2 & AirSpy with SpyVerter]
Burkhard Reuter mit seinem “Pocket”: Eine Entwicklung, auf die er stolz sein kann
Wo eigentlich bleiben die Weltempfänger? Die Spitzenklasse kommt heute nicht aus Japan und schon gar nicht mehr aus den USA oder aus Fürth, sondern aus: Dessau. Dort hat Burkhard Reuter unter anderem seinen Pocket entwickelt. Das ist ein Taschenempfänger, den es auch mit Sendeteil gibt. Seine Leistung ist absolute Spitzenklasse. Sein Konzept folgt einem ab initio selbst entwickelten und “Spectrum Based Signal Processing” genannten Algorithmus. Alles an diesem Gerät ist schlichtweg außergewöhnlich: von der Leistung über die Wertigkeit bis zum Preis. Für die Titelgeschichte der Mai-Ausgabe 2017 der Fachzeitschrift FUNKAMATEUR habe ich Burkhard Reuter in seiner Werkstatt besucht, mir seinen Weg und sein Konzept erläutern lassen sowie seinen Receiver auf Herz und Nieren getestet.
Where have all the world band radios gone? The most recent one – and probably the best ever produced – emerged out of the workshop of Burkhard Reuter (pictured above) from Dessau/Germany, the city of Bauhaus fame. For the cover story (May, 2017) of the German FUNKAMATEUR magazine, I visited him and did an in-depth test of this smart receiver, following his unique “Spectrum Based Signal Processing” algorithm. His Pocket turned out to surpass reception quality of each and every world band radio before, scratching the performance of even professional table top receivers. Some versions of it also include a ham radio transmitter (QRP). Already another modern classics from the Bauhaus city …
24 broadcast channels demodulated in parallel on shortwave – and Airspy plus SpyVerter do need just a quarter of PC’s power!
Always being interested in SDRs with remarkable HF performance, Airspy and the matching up-converter, namely SpyVerter, attracted me. It is a 10-bit SDR, covering 24 MHz to 1.800 MHz (just Airspy) plus 1 kHz to 60 MHz by help of SpyVerter (+120 MHz). Both come in solid metal cases.
I did test this combo in detail on HF, i.e. under 30 MHz. It proofs to be a sensitive setup with a surprisingly dynamic range, ending up in clear recpetion of up to a nearly 10 MHz wide band. This may be recorded and eventually played “as live”.
The test has been published on 19 pages plus 25 instructive illustrations, and the PDF can be dowloaded here. It is a real hands-on test in real practice. This includes also weak signal reception of data, demodulating and decoding of 24 HFDL airband channels in parallel, DRM and FAX decoding (KVM70/Honolulu) and reception of Auckland VOLMET von 6.679 kHz via long path.
The result ist simply stunning: if you are in search for a “low cost, high perfomance SDR”, that’s exactly is it. Yes – Youssef and his team advertise it with this claim, but it is one of the rare cases where such a claim meets reality. Be surprised, become convinced!
French version: Bernard Malet was so kind to translate the paper into French, merci!
Téléchargez ici, s’il vous plait.
One hour in the 20 m ham radio band with LimeSDR and SpyVerter, zoomed out of a one hour’s recording of 30 MHz width. Antenna: quadloop of 20 m circumference.
LimeSDR is a Crowdsupply project – delivering an SDR which covers 100 kHz to 3.8 GHz with bandwdiths of up to 2 x 30 MHz. I was interested almost exclusively in the range 100 kHz to 30 MHz. The board arrived on March 17th, and I already have done some tests with it. From these very first results & a recommendation:
- Installing is easy (W10), if you follow the instructions.
- Without modification, LimeSDR is simply useless on HF. It’s deaf near to a dummy load.
- The producer recommends a “modification” by just removing one SMD. Then some life came into this range. But it was hard to sort the ghost stations from the real ones.
- Even a low-pass filter from Heros didn’t helped that much.
- Just before selling the board on ebay, I connected the antenna first with Spyverter – a state-of-the-art up-converter with an IIP3 of +35 dBm, transferring the band of 0 – 30 MHz to 120 – 150 MHz. This is a range, where LimeSDR sees some light.
So, if you are disappointed by the near-non HF performance of naked LimeSDR: an able up-converter will change the game. Recording and sonagrams had been made with SDR-Radio.com V3.
30 MHz live with LimeSDR and SpyVerter shows that it generally works. Same antenna as above.
“Ghost signals” make it sometimes difficult to distinguish them from real signals. This sonagram has been made with SpyVerter. Broadcast stations are easy to find out (in their majority). But it gets difficult to sort the ghost stations from the few real ones in the left part.
Alaskan station HAARP is re-activated for some scientific purposes in late February, 2017. I received them on 2.800 kHz as well as on 3.300 kHz with carriers showing their scheduled pattern. Alas, reception was too weak to make out any modulation. See screenshots below, containing all sufficient data like time, frequency, resolution etc. Reception has been done in Northern Germany with FDM-S2 by ELAD at a quadloop antenna of 20 m circumference.
A strong combination: State-of-the-Art SDR transceiver Zeus ZS-1 and digimode software FLDIGI. With a step-by-step instruction, the combination of both with audio in/out, keying and freqeuncy transfer is easy.
With software-defined radio or SDRs, also ham radio has made a considerable leap forward. SDR transceivers are around for many years but failed to have a major impact until now. Among these transceivers, Russian and German-made Zeus ZS-1 is an outstanding example, covering each amateur radio band from 160 m to 10 m with up to 15 watt output. It received enthusiastic reviews around the world, e.g. by RadCOM of RSGB and QST of ARRL with excellent ratings.
Recently, I again bought on ZS-1 to re-vitalize my amateur radio activity with also again a focus on QRP and digital modes. For this purpose, ZS-1 with its outstanding clean signal under transmit and Receiver plus tidy interface is almost ideal. BUt Ehen I needed a fool-proof instruction to set up the combination of ZS-1 and a multimode software like FLDIGI, I didn’t found what I need: a step-by-step approach.
This was the reason for writing such an instruction by myself. I concentrate on the combination of ZS-1 and FLDIGI which in a PDF is laid out in detail and with instructive screenshots. In an appendix, I go also through some other digimode software like FreeDV and EasyPal. To my own disappointment, I couldn’t get work WSJT/WSPR. So your help is very appreciated!
You can download the 20-paged PDF with its 24 screenshots right here.