smps hv spike problem

[5282]

i make some research on smps before i make on for 220v .
so i powered my transistor with only 5v and reduce all component value

the problem is in two things
1- high voltage spike on transistor collector  it's 50v and some time 30v and all this high voltage come from 5v suplly
2- the high high frequency switching around 500khz
here is the oscilloscope screen shoot  from transistor collector in attachment file

[Miyuki]

"simple" 50 years ago  now with integrated power controller like TNY and similar is no reason to experiment with self oscilating flyback it is beast
waveform look ok for this type of circuit maybe snubber is not tuned right or use bad components

And how you probe it ? May be just ground lead induced noise

[5282]

thank you.
i found the problem . i must to put load in the transformer output. to reduce the reverse voltage from transformer .
.when i put the circuit in 220v the high reverse voltage kill the transistor. so i need load or feed back circuit

[5282]

here is my reverse voltage after i put load to transformer it's reduce from 50v to 12vpp. and i use good snubber circuit .
the oscilloscope screen in attachment