I just received a QA403 and I am seeing a low voltage from USB power in the app (4.317V). I tried a couple of hubs as well as directly connecting to my laptop and all read 4.3V or lower. I am using a short USB cable with 22ga wire. While the unit is working this voltage looks too low for full and reliable functionality.
Any suggestions on a powered USB hub that will deliver appropriate current without loading down the voltage?
Hi, i use this USB hub it is a bit Expensive but it Has an External Power Connector as well.
Have no Problem so far with it.
When i remember me right 4 Ports can handle each 1,5A at once
My best Cable 1,8M
This Short one works also:
https://www.dinic-shop.de/edv-u-smartphone/usb/usb-2-0-kabel-und-zubehoer/usb-2-0-kabel-a-auf-b-st-links-abgewinkelt-1m-awg-28-24-schwarz.html
May be an Alternativ one, with 4 Ports up 1A each:
https://www.exsys-shop.de/shopware/de/kategorien/usb-hubs/usb-hubs/1343/4-ports-usb-3.2-gen-1-metall-hub-fuer-tisch-wand-und-din-rail-15kv-esd-schutz?c=13
Robert
I have been using this w/out any problems:
Thanks everyone for responding.
I ended up using the Ikuai hub off Amazon. It was cheap, arrived quickly, and worked.
It is also essential to us a USB cable with 20ga or larger power conductors. Just using any USB cable I had around caused voltage loss. I am now seeing 4.75V.
Glad it is working out for you. I also like having the on/off switches on the outlets 
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