Über dc7ia

Joshua interessiert sich neben Amateurfunk auch für nordische Sprachen. Er ist Volunteer Examiner für das ARRL/VEC und ein großer Freund von Skandinavien im Allgemeinen und Schweden im Besonderen (Heja Sverige!) und mag gerne Sprachen. Neben Englisch spricht er auch noch Schwedisch und lernt noch weitere Sprachen. Leider hat er viel zu wenig Zeit für den Amateurfunk und kommt nicht so häufig dazu wie er will.

Five Months Now: Denmark

(I had to edit the title twice, as I never found the time to finish this article. :D)

I have now been living in Denmark for five months. And everyone is so relaxed, I have never had a stressful day so far. Seriously, people in Denmark are far more relaxed than Germans become on their best days. Everything is digital here and good wifi is common. And the train system actually works!

When I came here, I was surprised by the possibility to pay contactless with my card. Paying is very different compared to Germany. Cash isn’t used a lot while card payments, or payments using an app called MobilePay, are common literally everywhere. Even if you are at Copenhagen Main Station and you need to go to the toilet. Of course you just take your card and wave it in front of the reader and you go in. But not only near the trains you can pay with cards, you can also buy drinks from vending machines on the faster Eurocity (EC) trains. You just insert your card and choose from one of three buttons. It does not get any more simple. Often you will find signs at the entrance of restaurants telling you that they take „CASH ONLY“. And it is in English, because not the Danes use cash, but the tourists. Sometimes you even see signs „No US-Dollar“. Danes seem to think „Why bother getting cash to the bank account by carrying it to the bank?“ and simply let you make card payments. The app MobilePay is often used for small purchases. Often you will see a basket filled with apples from someone with an apple tree standing along the road, but it could also be a box filled with books or anyting else. A slip of paper says MobilePay and a number with 8 digits. This is a Danish mobile phone number. You just take an apple and send some money to the seller using their number and then walk away with your apple.

But that is not the only thing that showed me how modern Denmark is. Being gay is perfectly normal in Denmark and people don’t really seem to hide. Even in the school where I’m currently volunteering, you can see gay couples holding hands and all that stuff. It is not like in Germany where they would bully their classmates for that. In fact, it seems to be a thing nearly everyone agrees upon: There is nothing wrong with LGBT* people, a lot more people think that than in Germany or the UK. I have talked to the teachers about that and apparently they don’t have bullying in Denmark. You are just the way you are and others just let you be like you are. That is jolly good!

It is also quite common to see a lot of people with rainbow bags and other things with rainbow on them. That I have never seen in Germany, there it is not common. Just like the good mobile networks here. I just happen to have connection all the time, everywhere and even on trains in tunnels. Most of the time I have a 4G connection, sometimes it drops to 3.5G. I pay around 13 € / month and get 10 hours to call 50 countries, 3000 texts and 60 GB of data. And I use it: Just last month I used all the data.

Some of the usage happens while being on the train to the next amateur radio clubstation. Located in Amager which is a part of Greater Copenhagen, OZ7A is a clubstation in a small shack and with an antenna tower. There I am often on Thursdays to chat and contact the world. Often I talk to friends and this is my way to stay in contact with Germany. Sometimes I reach someone in Sweden and then I practise my Swedish a little.

Speaking of train travel, that is really simple in Denmark. Comparable to the Oyster Card, the Rejsekort is a simple RFID-based system. Rejsekort literally means ‚travel card‘ and I could not have chosen a better name. You can use the card for all means of public transport. Be it trains, busses, ferries or even the metro: This is the way to travel. Since I have not yet used the card for anything else than trains, I can only report about that. Usage of the card is pretty straight forward. You wave it in front of a reader labelled ‚check in‘ on the platform. Then you get on a train and when you change trains, you simply check in again. At the end of you journey, you go to a reader labelled ‚check ud‘ to check out. The system knows which trains you have taken and automatically takes the lowest price for that journey from the card. I wonder if we will ever get anything similar in Germany. Best of all: The trains are not dalayed all the, like in Germany.

But people of ask what I do all day. Since I’m doing a voluntary service at a school, I’m doing school related tasks. Some examples include checking rooms of the pupils, giving them everything they need to clean their rooms, being present in German lessons and supporting there (they somehow think I am competent in German, no idea where they got this idea from), helping the caretaker tidying up and throwing old stuff out and a lot more of similar tasks. I have even taken down an old antenna mast from the roof. A storm destroyed the unused antennas, so it was chopped of and the antennas landed in trash. I also replaced some lamps in rooms, some were old and fell apart.

I will continue to be here until June and I hope to find the time to write one or two more articles before I leave.

Cambridge or There and back again

I have been in Cambridge around two weeks ago, 2nd to 7th April, and I have spent a great week there.

I arrived on Monday at Stanstead airport, where Martin (G3ZAY) picked me up. We drove to Dom (M0BLF) who has been my host for the week. We had dinner and then it became late. I had some strong tea, which proved not to be the best idea I ever had. With a little bit less sleep than needed, my first day in Cambridge was about to begin.


Tuesday morning began with Martin (G3ZAY) taking me into Cambridge. Dan (M0WUT) showed me all the sights and I made same great photos.

Then, after lunch with Martin (G3ZAY) he had taken me to the Secret Nuclear Bunker in Kelvedon Hatch, which isn’t secret anymore, but „a large underground bunker maintained during the cold war as a potential regional government headquarters. Since being decommissioned in 1992, the bunker has been open to the public as a tourist attraction, with a museum focusing on its cold war history.“ (Wikipedia article). Unfortunately I do not have photos from there as it is forbidden to photograph in there. Some photos can be found on the internet, though.


In the evening I had the chance to make some contacts in the UKAC 144 MHz contest with the Camb-Hams. We drove on a small hill and had some fun there.


On Wednesday, I went to the Imperial War Museum in Duxford with Martin (G3ZAY) where I’ve seen a lot of planes.

Martin (G3ZAY) had then taken me to Ely where we looked at the Cathedral. Admission was too expensive, we decided.

After having looked at the cathedral, we walked back to the car park and then met Michael (G7VJR) at his company and had a chat accompanied by a cup of tea.






In the evening we then went to the Camb-Hams Pye & Pint. That’s basically around 30 radio amateurs meeting in a pub eating good food and chatting about their hobby. A great evening.



On Thursday, I was taken to the RSGB’s HQ in Bedford by Richard (G4AWP) where Steve (M1ACB) gave us a cup of tea and a tour of the HQ. Then we drove to Bletchley Park, where I met John (2E0XLX) and we walked around and visited all the huts. Bletchley Park is where the codebreakers in WWII broke ciphers of the Nazis and helped to end the war much quicker. Today it is estimated that it could have shortened the war by some years. Maybe you have heard of Alan Turing, the man who built the Alan-Turing-Bombe which made decoding the ciphers of the Enigma, the cipher machine used by the Germans, possible in the first place. You can even see the Teddy Bear of him.

GB3RS: I made a few QSOs at the clubstation in the National Radio Center.

In the evening, I watched some Torchwood episodes (season 2, episode 6 „Reset“ and episode 12 „Fragments“), as well as the Doctor Who special The Day Of The Doctor at Rob’s (M0VFC) with Dom (M0BLF) and Martin, (G3ZAY).


On Friday, Martin (G3ZAY) took me to the Ofcom listening station (PDF, link now dead), where Gavin (M1BXF) joined us. Jenny (G0VQH) gave us a tour of the antenna farm. Later that day, Martin (G3ZAY) took me to the Cambridge Centre for Computing History. It has been interesting to see all those old computers. But most of the exhibiton was about gaming over the last decades, which wasn’t really interesting to me. In the afternoon, I went to the Prana Indian Restaurant in Cambridge with Dom (M0BLF) and Lawrence (M0LCM). That was the first time I’ve been to an Indian restaurant. We then went to the Cambridge105 studio.


So long, and thanks for all the fish. – Douglas Adams

I then had to leave on Saturday. My plane was on time and I left the UK around midday. 🙁

I hope to come back to the UK.


Thanks to Dom (M0BLF) for hosting me for that week.
Thanks to Martin (G3ZAY) for driving me to all the places.
Thanks to Dan (M0WUT) for showing me all the sights.
Thanks to Michael (G7VJR) for the cup of tea.
Thanks to Richard (G4AWP) for taking me to Bletchley Park.
Thanks to Steve (M1ACB) for the tour of the HQ and the tea.
Thanks to John (2E0XLX) for being my companion at Bletchley Park.
Thanks to Rob (M0VFC) for the great evening on Thursday.
Thanks to Gavin (M1BXF) for showing me the exposure compensation on my camera.
Thanks to Jenny (G0VQH) for the tour of Baldock.
Thanks to Lawrence (M0LCM) for letting me see how a waffle is made.
Thanks to the Camb-Hams for letting me play on their radios and making this week possible.

You are all amazing!

How I learn(ed) Swedish

As you may have noticed, I really enjoy learning and using Swedish. But how do I learn Swedish? For quite some time now, I have been able to have normal conversations and I’d consider myself to be at level B1 or B2.

Most of my learning happened using babbel.com, but as I’ve completed all the lessions a while ago, I’m just using babbel to refresh all the vocabulary. I can really recommend learning Swedish with babbel. You can try the first lesson for free. With babbel, it didn’t really feel like learning and therefore it didn’t feel like work. Which is why I really enjoy learning with babbel. Plus you also learn very quickly compared to a language learning course.

Since I’ve completed everything babbel could offer me for learning Swedish, I began to look for podcasts to train my listening comprehension. These are the podcasts I found especially helpful:

Radio Sweden på lätt svenska is a podcast targeted at people who have learned enough to understand normal spoken swedish. It’s spoken slowly and with a clear pronounciation.

Klartext is a bit more difficult, but still a bit easier than normal spoken swedish. Listen to it when the above mentioned podcast becomes to slow and boring.

Stockholmsnytt is a normal news podcast. Search it in your podcast app.

All of the above mentioned podcasts give you around 5 minutes of spoken swedish every day. And these five minutes make a big difference.

Språket (RSS-feed) is a podcast by the broadcaster P1, where you can learn about the Swedish language. A great way to keep learning as an advanced learner. They talk about different topics like grammar or sayings.


Sometimes, I also read newspaper articles published on dn.se or the articles on the website of radio sweden (sverigesradio.se)


A very important thing to do: Talking to people. So try to find someone to practice with. I do that via amateur radio or by talking to a friend in Stockholm once in a while. You can also train your reading skills by following Swedish folk on twitter.


I will keep adding material to the list on my wiki: https://wiki.dc7ia.org/doku.php?id=languages:swedish

Reise: Prag, Budapest, OE3A Wien

Prag, 25.10.2017

Straßenschild mit Geschwindigkeiten an der tschechischen Grenze

Geschwindigkeitshinweis a der Grenze zu Teschechien

Es ist Abend. Ich bin müde, denn heute morgen ging es früh los mit dem gemieteten Wohnmobil. Aber nach der Ankunft habe ich natürlich erst einmal den Transceiver aufgebaut und weil ich mich nicht mehr viel konzentrieren konnte, habe ich ein bisschen FT8 mitlaufen lassen. Auf dem Weg nach Prag bin ich an der tschechischen Grenze noch auf ein paar Schweden an der Tankstelle getroffen und habe mich kurz mit ihnen unterhalten. Eine Sprache will geübt werden und jede Gelegenheit muss genutzt werden.

Prag, 26.10.2017

Am heutigen Tag schaue ich mir endlich Prag an. Zuerst geht es mit der U-Bahn vom Stadtrand in die Innenstadt von Prag. Dabei ist das U-Bahn zuerst ein wenig schwer zu durchschauen, denn alles ist auf tschechisch und es gibt keine Beschilderung auf Englisch. Mit ein bisschen durchfragen

Rolltreppe zu den U-Bahngleisen

Die Rolltreppe führt zu den U-Bahngleisen

kommt man dennoch zu seinem Ziel.

Endlich in der Innenstadt, ging es zuerst in der Nähe der Moldau in ein kleines Café am Rande des Flusses. Dort mit Baguette und Milchshake gestärkt, ging es weiter am Ufer des Flusses entlang.

Prag, am Rande der Moldau

Prag, am Rande der Moldau. Blick über eine Brücke

Am Rand des Flusses verkaufen viele Künstler und Handwerker ihre kleinen Kunstwerke. Ich habe zwei sehr schöne Bilder gekauft. Erst wollte ich kein Bild kaufen, da ich befürchtete, dass das Bild anschließend im Rucksack zerknittern würde und anschließend nicht mehr schön wäre. Aber der Händler hatte eine kleine Papprolle, um das Bild zu schützen. Ein Bild sollte erst 600 Kč kosten, aber der Händler hatte gerade kein Wechselgeld und so verhandelte ich weiter und kaufte ihm zwei Bilder für 1000 Kč ab, was etwa 40 € entspricht. Der Händler, der schon befürchtet haben musste, kein Bild zu verkaufen, angesichts des Mangels an Wechselgeld, freute sich sichtlich das Bild noch verkaufen zu können.

Händler am Rande der Moldau

Ein Händler verkauft Bilder am Rande der Moldau.

Ein paar Straßen weiter entdeckte ich dann zwischen schönen alten Häusern die Figur eines Mannes, welche an einer durch eine Fensterscheibe geschobenen Stange hängt. Ganz schön kurios!

Figur an Stange

An einer durch ein Fenster ragenden Stange hängt die Figur eines Mannes

Beim weiteren erkunden der Stadt stieß ich auf das „Apple Museum“, welches allerdings nicht von Apple betrieben wird. Dort lassen sich viele alte Computer und anderes Zeugs bestaunen.

Ich bin zwar kein Fan von Apple, aber Apple ist eine große Firma, welche viele Entwicklungen bei Computern und anderen Geräten beeinflusst hat und so war es ganz interessant.

Blumenladen in Prag

Blumenladen in Prag

Nach diesem Museumsbesuch ging es weiter durch die Stadt und ich stieß in einer kleinen Seitengasse, unweit von der Moldau, auf einen schönen kleinen Blumenladen.

kongelig dansk ambassade

Die königlich dänische Botschaft in Prag

Etwas später lief ich zufällg durch eine Gegend, in der viele Botschaften sind. Hier sah ich die dänische, norwegische, finnische und japanische Botschaft im vorbeigehen.




Auf dem Weg Richtung Budapest, 27.10.2017

An diesem Tag war ich nur mit dem Reisen nach Budapest beschäftigt. Es ist nicht gerade viel passiert, aber mir viel auf, dass auf dem Weg die Slowakei das beste Handynetz hatte.

Budapest bei Nacht

Budapest bei Nacht


Budapest, 28.10.2017

An diesem Tag geht es endlich in die Innenstadt von Budapest zum gucken. 🙂


Unterwegs habe ich etwa 20 Wörter gelernt, die ich dann auch gleich bei jeder Gelegenheit angwandt habe. Ich hoffe bald mal wieder Ungarn besuchen zu können.

Wien, 29.10.2017


Die Clubstation OE3A

Auf dem Rückweg von Budapest nach Deutschland habe ich noch kurz bei OE3A vorbeigeschaut. Die Clubstation der ÖVSV Headquarters liegt im Wiener Neudorf. Ich habe spontan am CQ WW SSB teilgenommen. Danke OE3FTA und OE3MZC, dass ich mal ein paar Verbindungen machen durfte. 🙂

Anschließend ging es endgültig nach Hause, mit einem kurzen Zwischenstopp in Bayern.

Ich muss OE3A mal wieder besuchen. 🙂


Whoa. What a week. More than 80 Youngsters from 26 countries gathered in Gilwell Park. All have the same hobby: Amateur Radio. So that’s what we did for a whole week. Amateur Radio stuff.

Saturday was the day it all begun. Ryanair had some delay, so I came a bit late compared to all the others. I watched the end of the opening of YOTA, where we received our YOTA T-Shirts and some other stuff. We were then divided into five streams: Turing, Morse, Hertz, Tesla, Marconi.

Every stream had the same programme, but on different days. We had a programme in the morning, lunch from 1 p.m. to 2 p.m. and then our afternoon programme.

We had different activities, this is what stream Turing did:



In the morning we operated the special event station GB17YOTA, a really great station provided by the Camb-Hams ( www.camb-hams.com ). We used some Elecraft Transceivers with a lot of good antennas and we had quite often pile-ups. We were rotating at the stations for the different bands, so that everyone would use all of the sations during the timeframe for the activity. A cool thing is that you could hear a lot languages, because many operators answered to the distant station in their language, when they knew it.

In the afternoon we built a groundplane antenna for 17m. The wires in my team were all cut the same length, but the first wire was too short. So we ended up with an antenna for another band. We had some help from Lauren, M6HLR, who activated all 214 Wainwrights at an age of 12, and from her father (G0PEK). We antennas are leightweight antennas from SOTABEAMS that are made for SOTA.


We prepared for the Foundation licence exam. In the preparation have we learned how to tune a dipole, send and reiceive some Morse code (really slow), use the prefixes for British call signs in other parts of the UK and some other stuff. There hasn’t been a lot new for most of the participants, who already were licensed, except for the call signs.

After lunch have we begun to build a QRP transceiver for telegraphy on 17m, but the time was a bit short and I don’t think anyone finished in the short time. The transceiver kit was donated from QRP labs. It really has a lot of functions…


This is the day most happened. In the morning have we operated GB17YOTA again. See Sunday.

Our afternoon activity has been ARDF. This was completely new for me and has been a lot of fun. It really took me a long time to find all the hidden transmitters, but eventually I found them all.

After our afternoon programme happened something special, something unique. An experience you don’t have that often: We spoke to Paolo Nespoli, IZ0JPA onboard the ISS. But this contact was even more special than most ISS contacts, because it didn’t work at first. We could see Paolo using HamTV (2.4 GHz) and he heard us, but we couldn’t hear us. After some time we told him to raise the thumb. We then knew that the problem had to be aboard the ISS. Mission Control in Houston had been called and asked for a seond try. We had to wait some time. Then they called back. And we got a second try! Paolo has been floating to the Soyuz module. There he could use a working radio, 25 W instead of 5 W. But there we couldn’t see him, because the camera for HamTV is in the other module. That didn’t matter that much. We could ask out questions and then had some time to applaud, to let Nick, G3RWF, President of the Radio Society of Great Britain thank Paolo for the contact and to let Paolo say goodbye. It really was a moving experience. Thank you, Paolo.


RSGB call book from 1951 in the Science Museum in London

RSGB call book from 1951 in the Science Museum in London

We visited London on Wednesday, where we have seen the Big Ben in Westminster, 10 Downing Street, the Trafalgar Square and the Buckingham Palace, where we took the Underground to the Science Museum.

The group then went back to Gilwell Park, while I took the underground with DK3CW to 221b Baker Street, where I bought a Sherlock Holmes book.


For thursday, we could choose from different activities. Some went to the OFCOM receiving

early QSL cards

Some early QSL cards in the Science Museum in London

station in Baldock, where I haven’t been because the number of participants was limited to 40. Some have been operating GB17YOTA, completed their transceivers or

An early coil

An early coil in the Science Museum in London

did other stuff.


In the morning, we visited Blechtley Park, where we learned about the Enigma and Alan Turing’s work on decrypting the messages encrypted with it. Experts now believe that Alan Turing’s work shortened the great war by two years. We also visited the National Radio Center in Blechtley Park, where we could operate GB3RS, but I

Early RF technology

Early RF technology in the Science Museum in London

decided to visit the shop of the museum, instead of waiting for the transceiver to be free for me, where I bought two books about Alan Turing.

From the museum, we drove around half an hour to a SOTA summit, where we made some contacts, before we drove back to Gilwell Park. This was the last day, so had a party and some goodbyes. We received the results of the foundation licence exam and every participant received a books about DXpeditions.

Conclusion: I’d visit YOTA again, but the number of participants is limited and participants who have not attended a YOTA camp before are preferred.

An early Telegraph station

This is how early Telegraph stations looked like

Thanks to the RSGB, the IARU and all the organisers of YOTA 2017!

A telegram

A telegram in the Science Museum in London







More about YOTA 2017 from the Radio Society of Great Britain: http://rsgb.org/main/about-us/yota-2017/
There you can also find the Daily Diaries, some great videos about YOTA.

Paddle from DK3CW / old Morse key

Jakob, DK3CW compares a modern morse code paddle to an old Morse key in the Science Museum in London



#hamradio2017: See you again next year in Friedrichshafen

Also this year it has been nice to meet so many great people from all around the world. This year I stayed in the HamCamp again, this year organized by Gerrit, DH8GHH (thank you!) where meeting great people started.

Mr. T-Rex has been at the information desk of the HamCamp most of the time.

Friday, 9 a.m. I went to the opening of the Ham Radio. The mayor of Friedrichshafen talked a bit

The mayor of Friedrichshafen at the opening of the Ham Radio.

about the impact the fair has to the city every year and IARU president Don Beattie, G3BJ, covered the spectrum challenges of today, and IARU’s role in working for the future of amateur radio A bit later DARC president Steffen Schöppe, DL7ATE hands over the Horkheimer award to Fritz Markert, DM2BLE. Fritz has done a lot do make calculations needed for german amateur radio stations a lot easier.

After the Ham Radio had officially opened I went to the stand of the federal network agency and asked them if they could use some help in the amateur radio examinition and then they told me to come. Before I helped at the examination, I went to the RSGB stand and drank some really good tea there. Steve, M1ACB, told me tea had to be drunken with milk so I decided to give it a try. Thanks for enlightening me, Steve!

IARU president Don Beattie, G3BJ talked about the importance of the work of the IARU.

Then I went to the examination and helped a bit there. I then asked the organizer of the american amateur radio examination if he could use my help, but he told me he had 40 examiners, so I didn’t help there this year as a Volunteer Examiner.

The stand of the swedish amateur radio society SSA.

Most of the time I’ve been at the stand of the swedish amateur radio society, where I told people about the longwave transmitter SAQ and why this UNESCO world heritage is something special that should be kept in a the good state it is so future generations can learn things from it. Of course you could also find a moose at the stand. 🙂

It has been a really great experience to participate as an exhibitor and if my help is wanted in the future I’ll gladly join again. It has been very cool to have many conversations in Swedish and English. Especially in Swedish it has been cool to get some practice. Thank you Anders, SM6CNN och Hans-Christian, SM6ZEM that you have invited me. 🙂

DARC president hands over the Horkheimer award to Fritz Markert, DM2BLE

Where else do you have the possibility to talk to people from that many countries and learn new things?

At the stand of the swedish amateur radio society: A map with destinations in sweden

The stand of the SSA








See you next year in Friedrichshafen!

Bald ist es wieder soweit: Ham Radio 2017

– English version below –

Nicht mehr lange. Dann beginnt wieder das große Treffen von Funkamateuren aus aller Welt in Friedrichshafen. Funkamateure und Funkinteressierte treffen sich, um sich auszutauschen, neue Leute kennen zu lernen, Freundschaften zu vertiefen oder Freundschaften zu schließen. Nebenbei werden auch wieder Funkgeräte bestaunt und gekauft oder es wird über den Trödelmarkt geschlendert.

Ich freue mich persönlich wieder darauf, mit Leuten aus den unterschiedlichsten Ländern wieder mit mehreren Sprachen wieder sprechen zu können. Einige tolle Menschen treffe ich nur einmal im Jahr bei der Ham Radio. Ich freue mich euch dort wieder alle zu treffen und wundere mich, was euch jedes Jahr nach Süd-Deutschland zieht, denn es gibt viele Gründe, zur Messe zu fahren.


Bis demnächst, wenn es wieder heißt: Wir treffen uns am Bodensee



Not for long. Then the great meeting of radio amateurs from all over the world begins again in Friedrichshafen. Radio amateurs and radio interested folk meet to exchange, meet new people, deepen friendships or make friends. In addition, radio equipment is also admired and bought, or it is strolled over the flea market.

I personally look forward to being able to speak with people from different countries again with several languages. Some great people I meet only once a year at the Ham Radio. I am looking forward to seeing you all again and I’m wondering what attracts you to South Germany every year, because there are many reasons to go to the fair.

Until soon, when: We meet at Lake Constance


Using Android – but without Google or other proprietary Apps

I didn’t like the fact that Google and maybe some other companies could spy on the activities on my phone, so I decided to remove everything that comes from Google. After some time I also thought it was great to only use open source software where many people usually read the code, making it more secure. If just the company producing it has the code, how can I be sure the App does what is says it does?

I found some great alternatives for every App I use and I want to share what I found good. All apps have been installed via f-droid store.

Amaze – A great file manager. Nothing more to say. Just works.

AntennaPod – Podcatcher. Listen to your favourite podcasts. Supports different podcast directories: Popular iTunes directory, fyyd and gpodder.net. Lets you change the speed to listen faster, import/export subscriptions via OPML, automated downloads and a lot more.

DAVx⁵ – Lets you sync contacts and calender, formerly known as DAVdroid. „DAVdroid is a CalDAV/CardDAV synchronisation adapter for Android 4+ devices. Use it with your own server (like Nextcloud, Baïkal, DAViCal or radiCALe) or with a trusted hoster to keep your contacts and events under your control.“

Dimmer – Maybe you know Twilight? It dimms your screen at night and changes the colour of the screen, making it easier to read the screen in a dark environment or simply while in bed.

Easy xkcd – A simple, but also feature rich viewer for the xkcd online comic. Lets you save your favorites. Can also show you ‚what if?‘.

Etar – A calender in material design, fork of the AOSP calender.

F-droid – App store for open source apps. Lets you add alternative app sources.

Firefox – A browser for the phone, features: tabs, sync, private mode, addons, …

FFUpdater – A simple app to download and update Firefox, which isn’t in the F-droid repos.

FoodRestrictions – “ When traveling abroad, are you having a hard time getting your food restrictions across? This app is here to help you ordering food when you are traveling to a country where language barriers can make it difficult to make yourself understood.“

Gallery – View your photos.

K-9 Mail – In my humble opinion the best mail client available. Also supports encrypted emails, multiple accounts and more.

LibreSignal – The great Signal messenger. Only that it is completely open source and doesn’t contain binary blobs as Signal  Update: Now longer developed, as you can now download Signal directly from the developers. https://signal.org/android/apk/

MemeTastic – Lets you create memes. Contains some popular pictures to which you can add text.

Mitzuli – Offline Translator. Great alternative to Google translate.

MuPDF – View PDFs.

Nextcloud Notes – Write notes and sync them to your nextcloud.

NewPipe – Youtube player app which lets you play the video in background.

Notepad – Just a simple notes app.

ObscuraCam – Helps you to obscure people from photos. (Just add the package source to f-droid, if you want it: https://guardianproject.info/fdroid/repo )

OCReader – A great alternative to feedly. Uses the nextcloud app ‚News‘ to sync rss feeds and always have the same news list – including read and saved – across devices.

Offi Directions / Öffis – Navigation using public transport

OpenCamera – Lets you take photos.

OpenVPN for Android – Connect to OpenVPN servers.

OsmAnd+ – Map and navigation based on Open Street Map

Plumble – Connect to mumble servers. Speak with people via internet.

Calculator – Calculator which lets you also use pi, log, sin, cos, tan and ().

Slide – App for Reddit. Many features, easy to use.

Sound Recorder – Record audio.

StreetComplete – „Help to improve the OpenStreetMap with StreetComplete! This app finds incomplete and extendable data in your vicinity and displays it on a map as markers. Each of those is solvable by answering a simple question to complete the info on site. The info you enter is then directly added to the OpenStreetMap in your name, without the need to use another editor.“

Suntimes – Useful if you want to when the sun rises or sets. Also has the nautical times.

Survival Manual – Survival Manual based on the US Army Field Manual 21-76, works offline.

Transistor – Save URLs and listen to radio stations. Very simple, does not do more than that.

Telegram (f-droid version) – It is just like the Play store version, but competely open source. Does not include Google stuff.

Twidere – A client for twitter, Mastodon, Fanfou and StatusNet.

VLC – The well known video and audio player with many features. UPDATE: App hasn’t been updated in f-droid for some time. Maybe get it here: https://www.videolan.org/vlc/download-android.html

WiFiAnalyzer – „Optimize your WiFi network by examining surrounding WiFi networks, measuring their signal strength as well as identifying crowded channels.“

Yalp Store – Download apps from play store, but without any code from Google running on your phone. Be aware that many apps still connect to Google.

ZANavi – Navigation app. Mainly for cars.


Syncing data without Google:

For that task I use my own nextcloud server. Contacts and Calender are synced using DAVdroid. Notes are synced with nextcloud app ’notes‘ using android apps ‚Notes‘.


How to use every bluetooth CAT dongle with RepeaterBook – now without root!

Last time I showed you how you can use any bluetooth CAT dongle with RepeaterBook. This time I show you how to do the same but without the need to get root access. Everything is the same except how we get to that file and get it back to the device.


  • You have ADB (Android Debug Bridge) installed
  • You have a USB cable for your phone
  • You have enabled ADB debugging for your phone (if not: just google it)
  • You have Android Backup Extractor on you Computer, get it HERE.

Extracting the file

First of all we need to get the file com.zbm2.repeaterbook_preferences.xml from the device.
To do that we just type in a command line: adb backup -noapk com.zbm2.repeaterbook

Confirm to backup on your device. You mustn’t use a password in order to follow my tutorial.

You will find a file called backup.ab in your current folder. We need to get a backup.tar file out of it.
Now we type: java -jar abe.jar unpack ~/backup.ab backup.tar

After that you will find a file called backup.tar. You will find the file we are looking for under the subfolder apps. Open the file and edit it as I explained in an earlier post. Save it and update the .tar archive. The exact way depends on the software you use. Try googling it if you have no idea.

Getting the changed file to the device

First we need to make a new .ab file from the .tar file. To accomplish that, we type: java -jar abe.jar pack backup.tar backup-new.ab 

Restore the file to your device: adb restore backup-new.ab

Just confirm that you want to restore. That’s it.

Just the usual note: I take NO responsibility if you are a not capable of using your brain and/or your computer correctly and then damage something. Following this tutorial could kill cats if used wrong and without caution.


Immer wieder habe ich mich schon für Satellitenfunk interessiert, bekam allerdings von anderen Funkamateuren nur Aussagen zu hören wie: „Das ist sehr kompliziert“ oder „Das ist riesiger Aufwand“. Also habe ich mir die vom DARC Verlag angebotene „LP145435SA, 2-m-/70-cm-Duoband-Antenne“ gekauft und an meinen FT-817ND angeschlossen. Ich habe mir die Frequenzen für die Satelliten schon vorher einprogrammiert. So habe ich es nicht so schwer beim korrigieren des Doppler-Shifts. Je Satellit kommen so fünf Kanäle zusammen.

Kanäle für Satellitenfunk

So macht man sich es auch ohne CAT-Steuerung unterwegs sehr einfach.


Die Benutzung ist dabei sehr einfach: Zuerst schalte ich auf den Kanal mit „AOS“. Sobald ich den Satelliten schlechter höre, schalte ich einen Kanal weiter, bis ich als letztes den Kanal mit „LOS“ eingestellt habe.

AOS steht für Acquisition of Signal
LOS steht für Loss of Signal

Ich hielt die Antenne einfach mal bei einem Überflug von SO-50 nach oben oben. Sofort hörte ich eine deutsche Station und rief. Und sofort bekam ich „59“.  Mein erstes QSO mit SO-50 war schnell gemacht und deutlich einfacher, als erwartet.

Natürlich lässt sich so nur mit den FM-Satelliten und nicht mit den SSB-Satelliten arbeiten. Dafür möchte man die Doppler-Korrektur per CAT-Steuerung nutzen. Es wäre nicht sehr praktikabel so viele Kanäle für SSB einzuprogrammieren und weiter zu schalten.


Falls du das auch einmal ausprobieren möchtest: Die Kanalliste gibt es hier als universelles CSV file.

Kanäle für FM-Satelliteauf n als CSV

Für 2m muss keine Doppler-Korrektur stattfinden, für 70cm ist diese allerdings notwendig.


UPDATE: 08. Dezember 2016: Die Kanäle korrigiert. Bei einigen passte der Doppler-Shift nicht.
UPDATE: 29. September 2020: Formatierung, Struktur, AOS und LOS erklärt