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 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 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 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

Tough day at the office