First experiences with my 30m QRP transceiver

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Final shot of the rig, including labels, key and headphones.

This year I built a very nice 30m QRP transceiver, based on a design by Onno PA2OHH. Meanwhile I have used this rig a couple of times, and did some measurements too. This article tells some of my experiences with this great little box.

GM/PA3HCM/p

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QSL-card sent by Jan PA1JT

The main reason to build this transceiver was to enable radio contact with friends in Holland during my hike in Scotland, September 2014. I built a lightweight antenna, based on a aluminium tent pole (4 meters tall) and a wire dipole (2 x 7.5m). The result is an inverted-V antenna.

Due to bad weather conditions during the first day, we had some exhausting walks through a landscape that was turned into a large bog. Therefore I was not always able to setup the radio station, but I managed to make a range of QSO’s using this simple setup. It was nice to see walkers first laughing at me with my morse key, until I successfully contacted a friend; they asked me to send telegrams to their friends, which I refused due to regulations.

During most evenings I was able to contact Jan PA1JT, who made a 30m dipole just to contact me. Also, Adrian PA0RDA provided a weather forecast every night on a given frequency. This helped me to prepare the next walk. Unfortunately I was not able to contact him, he was not able to copy my signal due to local noise and sub-optimal antenna conditions.

I asked some friends to make recordings of my signal, since I was really interested in how my tone would sound. It appeared to be a very pleasant tone to listen to, and very stable too; the oscillator was rock solid. Just listen to this recording, made by Jan PA3EGH who built a 30m vertical especially for this occasion:

 

Measurements

The VERON organizes a ham radio fair each year, called (in dutch) “Dag van de Radio Amateur”. During this day there are lots of activities, including a flea market, talks, morse code challenges, home brew area, interest groups, etc. There is also a place filled with measurement equipment, allowing to bring your own stuff and see what it does. I took my homebrew 30m transceiver and tried to measure its sensitivity. I attached an RF signal generator, running at 10.125 MHz and turned down the output. I was able to hear the carrier until the signal dropped below -110dBm (less then 1 uV).

Using my HEDZ

A couple of years ago Adrian PA0RDA and I built a Half Extended Double Zepp antenna for 80 and 160m. On a rainy evening in November 2014 I grabbed my 30m transceiver from the shelf and attached it to this wire dipole, just to listen a bit. I heard stations from different countries, from Germany to Brazil! I then attached my morse key and tried to tune the antenna using my versa tuner. I succeeded and answered some calling stations. I made some nice QSO’s with stations throughout Europe. However, not every station was able to copy my signal due to my QRP power.

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