So, finally I did it - BITX40, diode D& blown (nice light and smoke)
It is "off the shelf" radio - I made it few months ago - and now I take it to upgrade software etc..
Power on - and smoke. but raduino still works.
so I disconnected power connectors from mainboard, rechceked polarity - all OK. Turn on - Raduino is OK.
I dedoldered diode, reconnected power to mainboard - all OK.
Just courious - what happened?