Noobie question re: Switching USB devices

[medical-nerd]

Hiya

I have 4 rtl-sdr v3 dongles that I am going to connect to an industrial 4 port hub that takes a separate power supply, all of which will be enclosed in a 1u rackmount case - with low noise power supply,cooling, ferrite loaded USB cables etc, etc.

Now for the newbie question - I want to be able to turn each dongle on/off as required.  As I understand it - the USB A male connector has the power pins longer than data pins so that power is connected first, and data pins will not be overloaded by trying to supply power.

Is this always true? Does this mean that I can't leave the dongle connected and just switch the vcc line? Do I have to use a 4PST switch for each dongle? 

Cheers

[Bear207]

Hiya

I have 4 rtl-sdr v3 dongles that I am going to connect to an industrial 4 port hub that takes a separate power supply, all of which will be enclosed in a 1u rackmount case - with low noise power supply,cooling, ferrite loaded USB cables etc, etc.

Now for the newbie question - I want to be able to turn each dongle on/off as required.  As I understand it - the USB A male connector has the power pins longer than data pins so that power is connected first, and data pins will not be overloaded by trying to supply power.

Is this always true? Does this mean that I can't leave the dongle connected and just switch the vcc line? Do I have to use a 4PST switch for each dongle? 

Cheers

Greetings,
This question about USB power handling is going impact a project I'm going to be working on in the near future. 
Sure hope someone here is able to provide some info or direction where we might find some insight.

Regards

[ez24]

I want to see what the experts say, but I bet a SPST will work.

[ovnr]

OP re-posted this in a different sub-forum which did get replies.

[Bear207]

OP re-posted this in a different sub-forum which did get replies.

Thanks for the redirect ovnr.


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