[Elecraft] Serial Connection for K2

[Tom]

That sounds like a better solution. UnfortunTely the eBay 8 port USB to serial does not have a case.
Thanks




-------- Original message --------
From: Matt Zilmer <mzilmer at verizon.net> 
Date: 06/11/2013  09:29  (GMT-05:00) 
To: Tom Blahovici <tomb18 at videotron.ca> 
Cc: don at w3fpr.com,elecraft at mailman.qth.net 
Subject: Re: [Elecraft] Serial Connection for K2 
 
Hi Tom,

I run a Win7Pro laptop with a ton of USB devices here in the shack.
There is a single 16-port USB hub to the laptop.  One of the
peripherals is a 4-port Edgeport.  I found that the only ferrite
needed is at the laptop end of the A to B cable for that hub.
Everything else is dead quiet.  The hub is quite sturdy, with a metal
chassis that I've connected to the shack ground.

The above replaced a number of hub "chains" and several USB to serial
adapters (plus the other peripherals chained onto inline hubs).  For
EMI issues, this was unmanageable and I replaced all this crazy USB
cabling with a single hub because I had quite a time diagnosing the
various RF noise sources (probably all were hub-based).

The ferrite also protects the laptop against RFI.   On certain MARS
bands, 11 MHz in particular, high output transmissions could cause the
laptop to reboot.  Not so any more.

Ferrite recommended is Laird Technologies, available from Digikey.  
240-2508-ND is the DK part number.  The largest core (19mm I.D.) can
accept 3-5 turns of a USB cable with a Type A connector on the host
end.

Hope this helps your situation.

73,
matt W6NIA

On Wed, 06 Nov 2013 01:27:59 -0500, you wrote:

>Hi,
>I see ebay has some 8 port Edgeports for $50.
>I’m looking to cut down on computer generate noise in my shack.  Currently I have 6 or 7 usb to serial adapters.  I reduced noise quite a bit as shown on the P3 using some ferrite cores but the whole mess is now quite a sore sight.  Not only that you need longer cables to wrap through those cores.
>So here’s a few questions: is it better to run one high quality USB cable to a  device such as an edge port and then run serial cables from there or have many usb to serial converters and extensions?
>Anyone have a source for properly shielded USB cables?
>Thanks
>
>On Nov 5, 2013, at 8:54 PM, Don Wilhelm <w3fpr at embarqmail.com> wrote:
>
>> Tom,
>> 
>> Use a USB to serial adapter with an FTDI chipset - the Prolific c