Hi Steve and forum
Thanks Steve!
For those specially who want to duplicate that easy set up.
That cicuitry enter imediately to resonnance and it is audible form the transformer whisteling.
In case no resonance, swap transformer sensing windings pin 10 and 1.
Then it is possible to play with potentiometer R4 and input voltge from 6V to 20V until good spot is obtained.
Watch always Ameter vs bubles.
Good luck
and again to evryone: DO NOT HANG GREAT EXPECTATION FROM THAT SET UP.
Best Regards
Yossi