[Elecraft] K3S Microphone Cable

Jim Brown jim at audiosystemsgroup.com
Tue Jan 16 23:47:58 EST 2018


Hi Garry,

As a genuine OF (born 1941) who still keeps trying to learn something 
new every day, I strongly suggest that you study the material on my 
website about The Pin One Problem. I own thousands of feet of high 
quality pro mic cables and about 40 pro mics. Yes, physics doesn't 
change, but some of what we have learned about it over the years is 
simply wrong.

If all of the gear in a station is properly bonded, everything in your 
home is properly bonded, including power, and all of that is properly 
bonded to your station, and if the input gains and output levels are 
reasonably well set, and if all cable shields are bonded to the chassis 
at the point of entry, and if all power for station equipment comes from 
outlets that either share the same green wire back to the panel or from 
outlets that have their green wires bonded together, there is no need 
for anything fancy in the way of cable, nor is there any need for 
balanced wiring.

There are two tutorials on power, grounding, and bonding on my website. 
One, written for installers and contractors for large and small  audio 
and video systems, was commissioned. You'll find it listed as a "white 
paper for the real world." The other is in the form of slides for a talk 
that I've been invited to give at ham events and to ham clubs on power, 
grounding, bonding, and audio interfacing for hams. k9yc.com/publish.htm

If I were in the position of defining standards for consumer audio and 
ham radio back in the '60s and '70s when the transformation began 
between hollow state and solid state gear, I would certainly have gone 
for balanced interfaces (i.e., shielded twisted pair). But that didn't 
happen, and we're stuck with unbalanced interfaces. The simple, solid 
engineering outlined in those slides is an inexpensive and dependable 
solution.

73, Jim K9YC

On 1/16/2018 8:09 PM, Garry VE7PNQ wrote:
> As good as the noise rejection of new pre-amplifiers are, I still find separation of shield grounding and the minus side of a mic input important with modern radios.




More information about the Elecraft mailing list