17m band mobile QSO with local stations

Saturday, while I was waiting on the road near Sinaia, I was surprised to hear a YO station in QSO with another one.
The surprise was the fact that I was in a valley and the frequency was too high to have a "local" QSO (18.144 MHz).
Of course, the real life often "beats" the theory, so I give a try and made the call for YO2MHJ...
Surprise! He answer back and we made QSY to 18.150 MHz where we had a beautiful QSO from mobile to fixed radio!
The approximative distance between the two stations was a little over 200 km and the path was over a 2k m mountain chain!!! (Sinaia to Deva)
The signal on my mobile setup was 59+20 in the clear with a very little QSB!
My mobile setup is a ICOM IC-7000 radio, followed by a LDG Z11 PRO antenna tuner and a Sirio Titan 4000 mobile CB antenna.
The interesting fact is that this antenna is a base load one with no ground connection wich made this antenna suitable for broadband HF operation.
In fact, I was able to work from 80m to 6m while mobile!

Here is a small movie about my mobile QSO:

I believe that two factors was involved:
-A high F0F2 and
-A high angle of radiation at both stations!

To be further investigated...

73!