i have a rf transmitter circuit beside my computer and this circuit needs power, so i thought why buying a battery as long as i have a usb port
i did read somwhere that the USB port can provide up to 500 mAmps ,,right?
well the problem is that i dunno how much current the rf transmitter needs,,,anyone??
does the usb port provide 5volts always ? or do i need to do anythin in windows or do program somthin?
thanks already for answers