[RFI] USB port closing

[Martin Sole]

Thanks to everyone who responded to my question. I also researched 
answers to this problem on IC7610 at groups.io.

So we have tried most things, the recommended Tripp-Lite shielded USB 
cable, added #31 clamp ons with 4-5 turns at each end of the cable, a 
small wire wrapped around the USB connector metal shell at the radio end 
and tied to the radio GND stud. So far nothing has worked and the 
station is still plagued with Win4Icom disconnecting after a few 
transmit periods. It's become even worse now in that on some occasions 
it is not only closing the port but the port can no longer be found in 
Device Manager requiring a complete disconnection of the USB cable to 
get it to be found again. This is happening with the IC-7610 but more 
worryingly it is also happening with an IC-7300 that was previously 
trouble free.

As I understand it the station is located inside the house and the 
connection to the outside ground is approximately 20 feet. Right now I 
can only assume there is a lot of RF inside the station though before 
moving things around in the same shack the IC-7300 was working perfectly 
for very long periods of time.

Thanks
Martin, HS0ZED






> -----Original Message-----
> From: RFI [mailto:rfi-bounces+w7rkn.7=gmail.com at contesting.com] On Behalf Of
> Martin Sole
> Subject: [RFI] USB port closing
>
> Hi,
>
> I'm writing this for a friend. He has an Icom IC-7610 connected to a
> laptop running Win4Icom. At anything over about40 watts it doesn't take
> many FT8 transmit cycles before Win4Icom will report a connection
> error,the error log shows port closed and the author's statement in the
> alert box that appears is that this is most likely caused by RFI.
> Accordingly, we want to deploy suitable ferrite on the USB cables. My
> thinking is that 3 to 4 turns around one of the medium or large type 31
> snap on's that DX engineering sells, at each end of the USB cable, would
> be a good start.
>
> Is my thinking here sound or are there other things we should try first?
>
> Thanks
> Martin HS0ZED
>