Petroleumgas stove made in Czechoslovakia by Josef Zeman in the city Chocen. Burners : A.B.RADIUS - PATENT - STOCKHOLM
It is good to see that you have got the stove working, but the left side burner seems to have 'underburn'.
Hi Dusan, a quick way to see what part is to blame, you can try inner and outer caps from the "bad" burner on the "good" burner. First only outer cap, then only inner cap and then both caps. When and if the problem re-occurs it will be easy to determine which cap is faulty. Sometimes it helps to polish the caps (also inside). You can also try both caps from the "good" one on the "bad" one. Best regards, Wim
If the underburn still happens after swapping the caps, as Wim has suggested, the you must think of changing the jet on the left burner.