As far as I know, your Strong receiver (like any other with a loop port) should not have any problems with getting +12 (or 13) Volts on the LNB loop port...
Did you mean that I shouldn't have any problem connecting the loop through port of my Strong receiver if my satbox has the power turn on? But ...

I'm connecting my Giniatech usb satbox to loop out of my Strong satelitte receiver (4653X) so I need to turn off the LNB power. I used the multimeter to measure the voltage of the RF IN and found out that it got same voltage (12V) regardless if the lnb power is on or off. I'm wonderring if it is a ...