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23 June, 2022

Reversing the inductor in the Chinese QRP antenna tuner makes all the difference

Like many I was disappointed with the Chinese antenna tuner kit "QRP manual days" back in 2014 and I never really got it to work. 

That was even after I had replaced the two polyvaricon capacitors. The two screws for mounting each of the variable capacitors were too long. The result was that they interfered with the moving plates of the capacitor and I ruined both of them. There was no warning of this in the manual, so beware anyone who buys this kit.

Despite fixing this, it didn't really tune anything. I later learned that it probably works for low bands like 80 m as it is, but I didn't notice that. I thought maybe the toroid core of the inductor was of inferior quality, but never really investigated it, so it sat unused on the shelf for 7-8 years.

14 June, 2022

SV8/LA3ZA part 2

Below is a map showing contacts made from Pythagorio, Samos, early June 2022 using FT8. I tried to contact as many entities (~countries) as possible and got to a total of 55. The main band was 30 m, secondarily 20 m. 40 m and 17 m were also used. 

My quarter-wave antenna @ 30m, shown to the left in the image, performed well, despite the high noise level from the adjacent high-voltage line. The image is in the direction of Turkey (South-East), which is not visible at the time of the image.

03 June, 2022

SV8/LA3ZA

The polymath Pythagoras was born on
Samos and his birthplace village is now
called Pythagorio.
For a short while I’m operating from Samos, Greece with my old K2 at 10 W output. Noise level here next to a high voltage line is S9+ on all bands except 6m, so only digital modes work. The K2's noise blanker does a good job of removing some of the noise.

The antenna is a quarter-wave vertical for 30 m which also tunes several other bands. It’s on the balcony with a 7 m Sotabeam glass fiber mast, on the left-hand side of the street in the image below.