If your psp is a phat you can put 1.50 kernel, if it is a slim you can't
that said
download the 3.80 1.50 kernel addon here
http://www.dark-alex.org/index_psp.php
get the 1.50 Firmware update here
http://www.psp-hacks.com/category/43
rename it as 150.PBP and put it on the root of your memory stick
run the app, and you're good to go
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