Re: USB Issue K3S


Art Greenberg
 

It might be a bad cable. I recently had an interesting experience with a USB connected machine that started exhibiting strange behavior. I never suspected the cable. But after trying a lot of other "fixes" to no avail, I finally gave in and changed the cable. And the machine started working normally.

--
Art Greenberg
WA2LLN
art@...



On Mon, Sep 21, 2020, at 08:23, Alan Baker wrote:
It's possible that it's not just cable length, it could just be movement of the cable and proximity to 'something' else.

I've had intermittent issues with USB disappearing and I know for sure that at least twice it happened just after I reached over the back of the K3S to check a different connector.
My 'cure' so far has been to unplug the USB connector on the back of the rig and re-plug it, whilst watching the Device Manager display on the PC it's connected to. I have an extension lead on the USB cable and unplugging it there and re-plugging has no effect. Re-booting the PC has no effect. Of course it could be that something is not quite 'seated' in the K3S, but as all other I/O works 100% reliably, I have my doubts. As I have a mess of cables behind the K3S, I suspect some form of mutual coupling, which gets disturbed when I reach over. I guess I should try some ferrites.

I'm taking chances by writing this, as it's not happened for some time, so I better watch out when I next switch on. :-D

73,

Alan. G4GNX


------ Original Message ------
Sent: 20/09/2020 22:50:20
Subject: Re: [Elecraft-K3] USB Issue K3S

I too had a problem when I reconnected a USB cable to my K3s. I found or so it seems the length of the USB cable is a problem. When I connected a 1.25 meter cable, the PC would see the K3s but would only RX with no TX, when fitting a 1.5 meter cable, it could not find the K3s at all. But when I tried a 600mm cable, BINGO, all’s well, PC found my K3s TX & RX. So I assume the shorter the cable the better, I am not a techy whizz kid so you tell me why 900mm of cable makes such a big difference? But it seems it does. Maybe my friend Andrew G8BYB might pick up on this thread as he may know more than me.

 

Ken G0HOF





Join Elecraft-K3@groups.io to automatically receive all group messages.