Page I.5: USB 5 volt external power
In my tests it have shown that use a USB without external power supply provides much trouble.
In order to overcome it I have built myself a power supply for the USB hub.
Started from a USB cigarette converter. Normally, you can usually take up to 2 Amp at 5 volts,
the one I found in the drawer looks however very weak so have probably a much smaller maximum current, but enough for my needs.
In connection with this, I also disconnected the Focus driver so it does not
take power from 5 volt USB. 5 volts gives
to low torque of the motor.
You can configure the controller as it takes power from the outside and can handle up to 8 Volts.
It's the same voltage that I feed to the camera, i will modify the setup so that camera and motor focus share the same 8 voltage.
A bit risky it is, step motors can provide some spikes on the voltage that in the worst case could destroy the camera.
But I trust it enough to make an attempt.