[Elecraft] Background Noise with Mike Plugged in to Rear, Mike Jack

[Bob McGraw]

Running my K3S, KPA500 and working 160M - 6M at 500 watts, using either 
a mike into the front of the radio, or my headset into the back, I 
experience NO RFI issues.  I don't have any toroids on any cables 
either.   I also run digital modes with a single USB cable between the 
computer and the radio.  All of these inputs/output stay connected all 
of the time.

As to using toroids, refer to the work that Jim, K9YC has written and 
published.   If you experience RFI and use toroids to resolve the issue, 
you have only put a band-aid on the wound.   I suggest looking at the 
antenna system, feed line system, and bonding of equipment cabinets to 
reduce RF at the operating position.

I don't see this as a need for Elecraft to look at the radio for RFI 
issues.  To many hams use the K3 series successfully without RFI issues.

73

Bob, K4TAX


On 11/23/2021 9:28 PM, elecraft-request at mailman.qth.net wrote:
> I also had RF problems with the CM-500 plugged into the rear mic jack.  The solution I?ve implemented so far was to wrap about 13 turns of the CM-500?s cord around a #31 toroid. It both shortened the cord which was way too long for my shack and eliminated the RF problem. A two-for-one solution.;-)
>
> On rare occasions I like to use my D-104 mic in the front panel jack.  It too is adversely affected with RF issues.  As soon as I get a moment I?m going to try wrapping it?s cord around a #31 toroid and hope it works as well there as with the CM-500.
>
> I hope Elecraft is looking at the front panel mic jack as well as the rear when looking at solving the RF issue.