Portable setup without using any notebook power supply

  • Two days ago I found this nice piece of hardware on Ebay.

    Out of that I build a solution how to power-up the lnb for a portable setup using a notebook with battery only.

    You see the bias-t connected to the 5V-usb to 12V cable, the F-cable from the bias-t using a F to SMA adapter to connect this to the rtl dongle.

    With this setup it is very easy doing portable operation on QO-100 without the need of an additional power supply..

  • You have to be a bit careful about the max. current which USB is capable. With enumeration, this is 5V/500mA (which at 12V is only 200mA) and this is ok. Without enumeration USB will only deliver 100mA and after conversion to 12V, there is not enough power for an LNB. If depends on how the USB device is recognized.

  • @DD0KP

    How clean is actually the 12V output?

    There is not much space in the USB connector housing.

    Should one rather add a filter and think about at least one ferrite core?

    Not that the short wave is disturbed in the surrounding area...