[Elecraft] K3s rear mic connector and shure SM58.

[Nr4c]

The Shire SM58 mic is a Dynamic mic and does not require bias (required only for electret mics). 

Sent from my iPhone
...nr4c. bill


> On Oct 6, 2017, at 7:27 PM, Richard Day <richard at richdayhealthplans.com> wrote:
> 
> Why did you turn the mic bias off?  Have you tried turning it on to see if
> it gives you the sound you need?
> 
> Rich
> KK4DZE
> 
>> On Fri, Oct 6, 2017 at 12:27 Joe Subich, W4TV <lists at subich.com> wrote:
>> 
>> 
>>> On 10/6/2017 11:36 AM, Jim Brown wrote:
>>> I'm with Bob on this. While the K3 and K3S DOES have a Pin One
>>> Problem at the rear panel mic input (the cable shield goes to the
>>> chassis through a capacitor), floating the cable shield is not a good
>>> solution, and it should be tied to the connector sleeve.
>> That may work with the K3/K3S which have a relatively low impedance
>> between the mic return and chassis.  Tying the shield to mic return
>> is a complete disaster on older rigs (FT-1000D, FT-1000MP, most Kenwood,
>> etc.) where the mic return is the emitter of the mic preamp which has
>> an *unbypassed* resistor and/or RF choke to DC return/chassis.  That
>> [relatively] high RF impedance is like connecting an antenna directly
>> to the mic.
>> 
>> 73,
>> 
>>    ... Joe, W4TV
>> 
>> 
>>> On 10/6/2017 11:36 AM, Jim Brown wrote:
>>> I'm with Bob on this. While the K3 and K3S DOES have a Pin One Problem
>>> at the rear panel mic input (the cable shield goes to the chassis
>>> through a capacitor), floating the cable shield is not a good solution,
>>> and it should be tied to the connector sleeve.
>>> 
>>> When a rig  DOES provide chassis at the mic connector, the balanced mic
>>> lines should be wired to MIC+ and MIC-, and the cable shield should be
>>> tied to the chassis. In general, it's also OK to tie Pin 1 and Pin 3
>>> together AT THE RIG and connect them to the chassis.
>>> 
>>> 73, Jim K9YC
>>>