Apartment Ham Radio

… or how to enjoy the hobby when you are not able to put even a simple vertical on your rooftop.

Restrictive communities, regulations, living in a rented apartment, there are many different situations in which one cannot deploy a normal antenna installation. Many hams are in this situation, some of them have given up on the hobby because of it, and some of us started like that and prevail. Here is a short compilation of ideas that can help an antenna restricted ham to start or keep being in the radio world and, of course, enjoy it.

Antennas in unfriendly environments

First of all, you are not doomed. There are some antennas that can offer you some degree of performance. Just take it as a challenge and try to make the best out of the situation. Keep in mind that most likely you will end up with a compromise solution, but at least you will be in the air. What I have been doing until now has been focused on trying different indoor/window antennas and different placements:
  • Experiments with different indoor antennas: during my apartment ham radio career I have mostly experimented with wire antennas, whip antennas and loop antennas. This last type is clearly a winner and the one that I am using currently. Since every case is a different case you just have to experiment and find the kind of antenna that will work in your situation. However I can highly recommend loop antennas over the others (a blog post will follow on that). A simple loop antenna can be prototpyed without complex components (see example from YO3GGX). Other hams also use window-mounted whips with some degree of success.
  • Experiments with different locations in the house: different balconies, different windows, different rooms, different you name it! Benchmark different options by using reverse beacon network, WSPR or websdr. Once you have an option just make it as robust and efficient as you can. Keep safety in mind as well and make sure that nobody will touch a radiating element.


One of my first prototypes: a bike rim-based loop antenna. Note: does not work well close to metallic blinds ;)

One of my first prototypes: a bike rim-based loop antenna. Note: does not work well close to metallic blinds ;)

Modes in unfriendly environments

Not everything is SSB, there are many other modes that will perform much much better in a restricted environment:
  • Digital modes: PSK31 is the most common starting point. Get (or build) an interface for your radio, install the software and start making contacts. These kinds of modes tend to perform very well even in hostile and noisy environments like an apartment. PSK31 is not the only one; there are many more (RTTY, JT65, WSPR…). Just experiment with different ones and find your flavour.
  • Morse code? Yes, or at least that is what they say. Here I have to be honest; code is something that is still not part of my skillset. However the ones that master it tend to agree on one thing: it is among the best modulations in restricted, low power setups due to its efficiency, and also because not a perfect, solid, tone is needed on the other end to get the message across. Sadly I cannot say more about it (yet), but this list would be incomplete without it.
WSPR reception with an indoor magnetic loop antenna

WSPR reception with an indoor magnetic loop antenna

Go portable!

Put together a QRP station, get away from the city, throw a wire to a tree and make contacts. As simple as that. And this can be achieved with a expenditure of 100€ in equipment.

My personal experience: This is one of the things that I enjoy the most and that I do relatively often (living in Scandinavia implies not as often as I would like). I use a Yaesu FT-817 and an outback multiband antenna (whip antenna). This typically results in contacts at the European level. In good days I can also hear North American stations but I still have not managed to work them (note that this is not impossible). I operate normally SSB in 20, 17 and 15 meters and it is always good fun.

One can also operate digital modes while portable. A smartphone or a tablet with the proper software will do the trick.
If you are still not convinced go to youtube and see by yourself what people are doing with a radio and a battery pack. You will not be disappointed!

Other radio related activities in unfriendly environments

Ham radio is not only operating, there are tons of other activities that can be equally entertaining. Here is a short list of things that one can do when not poring RF into the ether:
  • Kit building: There are many and very affordable kits on the internet that can keep you entertained for a long time. One of the mistakes many kit builders make is to buy the kit and start soldering and putting pieces together. One should not jump into de building part but study the manuals, the schematics, and read and understand how the device works. Only after that one could jump into the building mode. I can recommend the kits from EA3GCY, he provides high quality material and good support in case you need it.
  • Homebrewing: Amateur radio can very easily turn into using a home appliance, a sophisticated one perhaps, but still a home appliance. When homebrewing you take your initial kit building experiences one step further and you design and create your own equipment. The number of possibilities here are endless but a short list could be: radio beacons, simple receivers, antenna analyzers, QRSS transmitters, RF generators, APRS trackers… At the current time I am reading “Experimental Methods in RF Design” and I can highly recommended (it is a “remastered” version of “Solid State Design for the Radio Amateur”).
A picture of my ILER40 during the kit building process. This is a 40m QRP transceiver from EA3GCY

A picture of my ILER40 during the kit building process. This is a 40m QRP transceiver from EA3GCY

  • Arduino, electronics and programming: The Arduino platform has made the world of microcontrollers accessible to many audiences, being one of them the amateur radio community. Having a microcontroller in mind the number of projects you can do is several orders of magnitude higher than without it. A possible starting point can be Ham radio for Arduino and PICAXE and for somebody totally new the Starter kit from Arduino.CC
  • Stepping further into de software world: In case you are more in the software domain there are many radio related projects with a heavy software component (both in the system/server configuration side as well as in the development side). Just a RaspberryPi, an internet connection and a VHF handheld can keep you entertained for a while! There are more advanced projects such as the IRLP and infrastructure like DSTAR or Echolink which can also be an interesting aspect to explore or to build/prototype services for. Finally, one should not forget the Software Defined Radios (SDR), which are gaining more and more popularity due to their low cost.
  • Radio restoration: This is something that I have seen since I was a kid. My grandfather used to restore old vacuum-tube radio receivers. He was a carpenter by profession and an electronics amateur in his free time. The results of this combination were beautifully restored and working radio receivers in their original high-quality wooden boxes. Really eye catching results and a rewarding job. I am lucky enough to have some of this receivers in my shelves.
  • Keep reading and keep learning: self-explanatory. The RSGB and the ARRL have excellent publications and there are also blogs and podcasts discussing several aspects of the hobby (for example: the soldersmoke podcast). Reading and learning will not only enrich you, but it will also allow you to continue expanding the list that I have started in here with new ideas and projects.
Raspberry Pi based WSPR transmitter by Gerolf Ziegenhain

Raspberry Pi based WSPR transmitter by Gerolf Ziegenhain

Final words

Just remember: you are not the only one without a three elements Yagi on the rooftop, yet you can enjoy the hobby equally well (if not more!).

73s de OZ/EA2ECV

PS: This is not a closed list, if you have a suggestion please write a comment and share it with the rest!

Restoring a HP-23 for my Heathkit HW-100

Few months ago I got what some hams call a “boat anchor”: a Heathkit HW-100. What a beauty! It was the first time I was getting my hands on one of these old amateur radio transceivers and I was not expecting to need a special power supply for it. But it turned out that I needed to provide a range of different AC and DC voltages (including a terminal at 800 Volts DC)… So I started yet another project during my free time: to manage to power this thing. After doing some reading, buying a second hand old power supply, looking for the correct components and putting the soldering iron to work I had a power supply giving all the correct voltages to all the pins and I was able to turn on my boat anchor: I couldn´t be happier!

PS-23 after restoration

PS-23 after restoration

After completing this mini project I decided to write up a small technical note and make it available in this website. In this note I cover some of the important points of the process and compile some of the different bits and pieces of information I have used to restore an old second hand PS-23 unit. This PS that can be configured for several Heathkit radios so, if you are aiming at powering a member of the SB family some of the information that I present in there still could be useful for you.

For hams that started in the hobby +40 years ago this is certainly not interesting/surprising. However, for hams like me that have always lived in the solid-state world (get 13.8 Volts and you are free to go) the info I am recapping in here might be useful. As stated in the note I made: be very careful and double triple check your work before turning anything on!

Here you can see the power supply doing its magic and powering the radio, which in this case is receiving on the 20m band:

Book review: “SolderSmoke – Adventures in Wireless Electronics “

After finishing the Soldersmoke book I cannot do anything else than recommend it to fellow radio amateurs. Soldersmoke is written by Bill Meara (N2CQR), who also runs the Soldersmoke podcast on amateur radio, which already has thousands of fans around the world (being me one of them). Keep reading for a short overview of what you can enjoy if you decide to buy it.


A career in amateur radio

When it comes to amateur radio books I am used to read only technical material: electronics, antennas, equipment construction… the typical things that one would find in the ARRL handbook. This book is something else. Bill Meara presents his progress in amateur radio starting from his teenage years until present days. Bill starts explaining how were his early days in amateur radio and the difficulties that he had to go through. It certainly gives you a perspective on how was the world before the internet… After some years Bill eventually started working for the diplomatic service, a career that made him travel extensively around the world and hence having a QTH on the move until present days. There are many good stories about antenna setups in his different locations through the years, construction projects and interaction with the local ham communities.

A perspective of the hobby

One of the strongest points in this book is that it truly gives an overview of the hobby: amateur radio goes beyond operating ready-made radio equipment; it is also about studying, understanding experimenting and building your own gear. This is something that is made clear in the book and Bill made his case showing how amateurs can enjoy this process.

Verdict: Go for it!

While reading the book I was able to see myself in some of the chapters and I am sure the same will happen to many other readers. This is quite nice since it gives you a “you are not alone” feeling in your radio career. I am not too fond about the technical parts of the book (there are a few explaining key concepts) and an advanced reader will find them basic. On the other hand the explanations are good and very readable for an audience without a technical background.
To sum up, this book is an enjoyable reading for any radio amateur, no matter how many years you have been in the hobby. You can find it in amazon for kindle as well as in lulu.com as a hardcopy.


Voyager Spacecraft by RIA Novosti

The Voyager program launched successfully the probes Voyager 1 and 2 in 1977, and they have been traveling through space until present days. The probes are technically impressive and well know in the techie circles because of the golden records. The Russian news agency RIA Novosti captured some interesting aspects of these missions in the infrographic presented below. Click over the image for full details.


Original source RIA Novosti.

Approach to La Palma GCLA in an Airbus A320

I have just finished re-watching an amazing 1080p video of a Condor Berlin Airbus A320 landing at La Palma Airport (Canary Islands, Spain). The video was shot from multiple angles including cockpit and runway views. Cockpit conversations are in German but subtitled in English, conversations with ATC are in English. Reserve 6 min of your time, go full screen and turn audio on.

This video is part of the PilotsEye DVD, which might be in my next order to Amazon :)

Hope you´ll enjoy it!

Radio station up and running

After struggling with my schedule almost fully occupied by my PhD, projects and Danish lectures I managed to get some free hours to get my radio station up and running. Here it goes a brief description of my first steps in amateur radio.

After not very successful attempts with an Outback mobile antenna for HF I decided to use a long wire antenna (around 17 meters) connected to my FT-857 transceiver  through a Yaesu FC-700 antenna tuner.  My QTH is Aarhus, central Denmark and so far I have been transmitting full power (100W). The long wire was not specially high above ground, barely 1.5 – 2 meters. The results after some hours operating the station are quite nice!

16th of September, late afternoon. A few minutes after powering up and tuning the antenna for 14MHz I replied a CQ call from PA3GEG operating from the Netherlands, 490 Km away so not too impressive but still my first DX :) Following that I called CQ and reached further, this time the contact was with YT1AA operating in central Serbia (1500 Km away). Final CQ call was replied by RX3DF, operating 100 Km away from Moscow making a total distance of 1700Km. I tried to get into a couple of pile-ups, but stations from the eastern part of Europe were transmitting at 1Kw, so it was hard to get there with a tenth of that power. At that point I decided that I was done in 20 meters, and move up to the 18MHz band, where I replied a CQ call from EA2GJ operating from Bilbao, Spain. It was surprising to have my first QSO with a Spanish operator me being in Denmark (I am Spanish myself). That was the end of the radio session for that Sunday with a nice feeling of success!

22nd of September, starting at 19:00 UTC+1 summer time. Chilly outside, reading good propagation predictions, and getting ready to go back to 40 and 20 meters. I hanged out the same antenna as the previous day but this time my neighbor saw me and asked me if I was gonna fly a Kite :) I spent some time in 40 meters trying to make some contacts there, it was hard: many stations and the band almost crowded! I decided to go back to 20 meters and see how it was going there. Again nice results! This time I registered the contacts in QRZ.com and you can see below the logbook for that day: Ukraine, France, Bulgaria, UK and Russia again. The contact with Russia was quite nice: RA6ABO, Misha, replied my CQ call and he was 59, loud and clear. I got a 58 signal report from him and I was quite satisfied since this time I reached a station 2192 Km away with my limited setup.

My logbook in qrz.com at this point

Thanks to all the operators that were at the other end for the QSOs!


sudo apt-cache search LOL!



soon operating as

OZ / EA2ECV / Portable

Late forties computer bugs

Moth found trapped between points at Relay # 70, Panel F, of the Mark II Aiken Relay Calculator while it was being tested at Harvard University, 9 September 1945. The operators affixed the moth to the computer log, with the entry: “First actual case of bug being found”. They put out the word that they had “debugged” the machine, thus introducing the term “debugging a computer program”. In 1988, the log, with the moth still taped by the entry, was in the Naval Surface Warfare Center Computer Museum at Dahlgren, Virginia.

Source: US Naval History and Heritage Command.

Prometheus, Mild Spoilers