Geocaching is a popular hobby here in The Netherlands. Since my wife and I search for these caches from time to time, the idea came to me to build a cache myself, one that challenges geocachers to listen and decode morse code. This article describes how I built it.— more →
Almost every nerd is a fan of automation. So whenever we find a repetitive job, we think of a solution to automate it. Since I’m both into automation and amateur radio, I was thinking on automating one of my straight morse keys, in a bit unusual way, by building a mechanical hand that operates the key.— more →
AGCW is a german club of morse code enthousiasts, maybe the best CW club in the world, with lots of foreign members as well. They organize all kinds of small activities, related to CW off course, one of them being the “HandTasten Party” (HTP, straight key party). In this contest the only way to make a QSO is by using a straight key. So no bugs, no keyers, no computers, just the classic way. There are actually two HTP contests, one is on the 80m band every first Saturday of February, and the other on 40m every first Saturday of September. This year I participated in the 80m contest again, as a nice warming-up for the PACC contest. — more →The
After browsing the web for designs, I stumbled on the website of Onno PA2OHH. Besides lots of other interesting QRP projects, I found his NiceRig 40-30 QRP Transceiver. I immediately fell in love with this design and decided to build this thing.
Building this rig takes quite some time, so I publish this project in different posts, showing you the progress of this project. — more →
Last weekend was the yearly ARRL 160m contest. Adrian PA0RDA and I were still a bit in doubt about our HEDZ antenna for 80 and 160m: is it suitable to work American and Canadian stations at 160m? So far we never heard any station from that area on that band, so Adrian decided to bring his Drake TR-7 for the weekend and try to work these countries during the 160m contest, probably the best opportunity for this test. — more →
Since Adrian PA0RDA was ill during the contest weekend, and we were not able to setup all antennas due to poor condition of the field, we decided to skip the PACC contest. However, on Sunday morning I could not resist to give away some points, so I made a bunch of CW QSO’s on 15m. We hope for more luck in 2014.
Beacons and foxes have to identify themselves. Although I could sit along all day with my morse key, transmitting my call, I wanted to have some automatic keyer. Since I recently bought a PIC development kit (Velleman K8048), I thought that it would be a nice idea to create my first PIC application by building a CW keyer.
I never wrote PIC source code yet, but I have done some assembly for 68000 and x86 in the past. So it shouldn’t be to difficult to write a simple program, keying one of the outputs of a PIC. On the CD of my PIC development kit I found some sample programs, including one for a flashing LED (this appears to be the “Hello, World!” application for microcontrollers). I modified the source code and finally build the bunch of code which you can find on the bottom of this page. I’m sure that this code is not the best PIC program of the world, but it works and at least I understand how it actually works. If you have any suggestions, please feel free to send them to me! — more →
Fox hunting is one of the many aspects of ham radio. It’s some kind of game, where the “fox” is a little transmitter, and competitors have to locate it using a directional antenna and receiver. I already built a special receiver for fox hunting, and my wife (PD2W) built one too. So having 2 receivers it would be a nice idea to add a fox to these, to get a complete mini-fox-hunt-kit. One of the members at the club pointed me at the so-called “OXO transmitter”. I looked it up at the internet, and immediately liked its simplicity. So I started to build it.
The smallest QRP transceiver for 80 meters, called “Pixie 2”, is a very nice project to start building your own equipment. Minimum components, maximum fun. The spec’s are poor, but what else might you expect for just a few dollars?
In fact, it is only a simple Clapp Oscillator with the output directly driven into a few meters of wire. The transmitting frequency depends on the used crystal. This may be any crystal between 1 and 15 MHz, higher frequencies may perhaps work also, therefore you may lower the 2 capacitors a little bit.
The transmitting frequency is not only the one shown on the crystal, but also “harmonics”: If you have for example a crystal of 3.56 MHz, then it transmits (of course) on 3.56 MHz, but also a bit at 7.12 MHz (2 * 3.56), 10.68 MHz (3 * 3.56), 14.24 MHz (4 * 3.56), etc.
The operating voltage is not critical, a 9 volt battery will do the job.
- C1 – 100 picofarad
- C2 – 100 picofarad
- R1 – 10 kilo-ohm
- R2 – 1 kilo-ohm
- S1 – Morse key or switch
- T1 – BC547 or any other universal NPN transistor
- X1 – Any crystal you like between 1-15 MHz