On this beautiful sunny day Alex informed me that the start of a new M20 sonde is planned and the landing site should be near my QTH. So, I immediately got ready by loding all my direction-finding equipment in addition to my radiosonde tools into my car because we had to catch this sonde for reverse engineering purposes before anyone else could get it. When the falling M20 reached 4000m it passed over me and I started following it. Luckily, I am very familiar with all dirt roads in my area so I could quickly follow the radiosonde which was heading north (to do this on conventional roads a long detour would have been necessary). Finally, we decided to shut down the public receivers to increase our chances for getting the sonde. Furthermore, only a view minutes later the touchdown position was received. The M20 landed behind a graveyard next to the village Kibliz. When approaching the landing site, it was very noticeable that the signal is weaker than the signal of a M10 sonde. The red parachute was visible from far away since the radiosonde landed on an open field next to some trees. I simply had to drive there and take the M20, but unfortunately, I took the wrong dirt road so I ended up on the wrong side of a small creek. Luckily, it was nearly empty and I just jump over it. After picking up the radiosonde I saw that ’73 was written on it which means someone at ZAMG thought of us during the launch 😁.
On the following days I was busy reverse engineering the hardware of the M20. The first results can be viewed here . Reprogramming should be easy but for transmitting on ham bands the PLL inductor must be changed.