Page 1 of 1

Is USB Powered Hub Really Required

Posted: Sun Mar 24, 2019 10:49 am
by Nick
Wondering if I can just use a short USB extension cable (male to female), cut the supply cores in it and supply the 5V to the Lime SDR this way, leaving the 5V supply from the Pi disconnected, or maybe just connect the 0V lead from Pi to Lime and leave just the 5V line cut.

Has anyone tried this ?

Regards,

Nick.

Re: Is USB Powered Hub Really Required

Posted: Sun Mar 24, 2019 11:14 am
by g4eml
I am using the latest version Pi and I have found that it works fine with no Hub. Just connected directly to the Pi USB port.
I am using a good quality power supply of 5.2V

If I do find any issues then I plan to do something like your suggestion. I have mounted the Lime in a diecast box with a short connection to a standard B type USB socket, making it much more rugged. It would be easy to add a separate power connector to this arrangement.

Re: Is USB Powered Hub Really Required

Posted: Fri Jun 14, 2019 9:16 am
by M0IVJ
For some reason the Raspberry Pi would not reliably see the Lime SDR via the USB hub I have, and there wasn’t room in the case for it without moving things about. So in the end I changed a USB patch lead by cutting the positive wire (Isolating the Pi) and powering the LimeSDR from the Portsdown 5volt power.
PD_USB Power.jpg
PD_USB Power.jpg (40.91 KiB) Viewed 1305 times