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flyback + uc3842 + ripple output

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tictac

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Hi, I have made one smps with this specification.
Vout=100v to 1300v (variable), Iout=40 mA , Vin=22v - 30v (DC-2 Battery)
Controller IC=UC3842 , Transformer=EE50-42 , gap=1mm , Lp=14 uH , Ls=85 mH , Ip=14A, Np=9 Ns=600 , Bmax=100 mT

1-I have a ripple on output voltage!! its about 50 volt at 1300 volt
2-I have a sin wave on drain of mosfet when the mosfet turns off !!!
3-I have a loud audio from transformer!!

first I put 22 nF at output and it has some audio noise , after I put 220 nF at output and audio noise had gone but voltage ripple get larger!! I put the schematic of this circuit here. please help me to improve this.

https://www.4shared.com/file/222263306/14b17eeb/Schematic_Prints.html[/url]

its the picture of sin wave at drain of mosfet in dcm operation.

https://www.4shared.com/file/222275789/53d537c2/snubber.html
 

Is there any body to help me,please?

I add one resistor from feedback to pin 2 of 3842 and it was better.

please help me.
 

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