ok
the code is as was the provided by me old mate coding badly, the led was another seprate to board but as i was lead to believe pin 13 has inbuilt resistor for this purpose ( maybe not ha).over night i left it running with only board led doing the work and it is still working this morning,looks like i either need to provide seperate power source via switching transistor to led  or increse the resistance via a couple of resistors on  bread board,lesson learnt !
and thanks for your reply.

hi guys
would a hardware issue be causing led to hang on high after say 5 min or less,i am using uno smd with led in pins 13 and ground,and have only been fooling with random off and on times now longer on than off ?
cheers

thanks so much
but please dont tell me it took you less than than a day . it worked as expected and i dont think i will be looking for a new wife now!

hi guy's
 have been stumped for days on this one,trying to create chopper for water stream,and light show, have done code with delays and works and now wanted to change out to millis type program the theory is turn on led (will be stepper motor in future) then wait random time ,then turn off after seperate random time the code included is only one i would like help with
 thanks in advance