[Elecraft] OT Hearing HRD Communicate w/K3

[Don Wilhelm]

  Eric,

Joe is correct.

The fact that the noise disappears when the antenna is disconnected AND 
when you shut down HRD indicates that your serial cable and/or the USB 
to serial adapter is radiating trash and that trash is being picked up 
by your antenna.

Jim's suggestions are valid for that sort of condition - kill the bad 
stuff at the source, don't try to fix the symptoms (which is harder to 
do anyway).

73,
Don W3FPR

On 3/18/2011 9:10 PM, Elecraft K3 wrote:
> Hi Joe;
>
> Thank you for the reply.  As I mentioned to Jim , the noise completely disappears on RX when the antenna is disconnected.  This leads me to suspect that the RFI is coming in on the antenna cable.  Does that sound right?  If it was coming in on the USB to serial I would expect to still hear it when the antenna was disconnected.
>
> 73 de Eric, KG6MZS
>
>
> On Mar 18, 2011, at 3:22 PM, Joe Subich, W4TV wrote:
>
>> Replace the cable on your USB to serial interface and make sure
>> your K3 has all of the "RFI" mods, particularly those involving
>> the KIO3.
>>
>> What you are hearing is common mode noise from the USB cable that
>> is being radiated into your antenna or being conducted via the
>> RS-232 cable.
>>
>> 73,
>>
>>    ... Joe, W4TV
>