[Elecraft] K3 low PEP Power on SSB

[Don Wilhelm]

Knut,

Unfortunately there is no one crisp answer - one must know the 
particular microphone that he has in hand.

There may be a difference between a Kenwood (branded) microphone and a 
Heil microphone with an adapter for the Kenwood (or there may not be - 
it all depends).

Your Heil IC (electret element) mic with the Kenwood adapter will work 
just fine as long as you use the K3 menu to apply bias to the microphone 
AF line.  Bob Heil has assured me that all his basic microphones use 
only 4 signal lines - AF, AF Ground, PTT, and PTT Ground.  The adapters 
then map these 4 signal lines to the corresponding pin for the 
particular pinout defined by the adapter name.

As a result, any Heil microphone will work with the K3 when the mic is 
equipped with a Kenwood adapter.  If it is a dynamic mic, the K3 mic 
bias should be turned off in the menu, but if it is an electret element, 
then bias must be turned on.  Caution: you must know your Heil 
microphone element type - a dynamic element can be damaged if bias is 
applied to it.

I don't know if the same thing applies to all Kenwood branded electret 
element mics (should any exist) or not.  It will depend on whether the 
particular microphone design develops a bias derived from the pin 5 
voltage (which is most likely because AFAIK Kenwood transceivers do not 
apply bias to pin 1 of the mic connector).  If the bias voltage must 
come from pin 5, then that mic will not work with the K3 without 
modification because the 8 volt supply is on pin 6 of the K3 mic jack 
rather than pin 5 on the Kenwood.

This subject can have as many answers as there are microphones.  If you 
are unable to determine the compatibility of your particular microphone, 
I recommend first asking the microphone manufacturer which pins are used 
for what function.  There is also good microphone information at 
http://www.dxzone.com/catalog/Technical_Reference/Mic_wiring/index.shtml, 
and a very extensive listing of microphone pinouts and diagrams has been 
compiled by G4WPW.  We can provide information about the K3, but 
questions about microphones (other than Elecraft mics) will not have 
such crisp answers because there are so many variations.

If all else fails (or that process is too cumbersome), there are 
Elecraft microphones that can be purchased.  Additionally, the 
enterprising amateur can re-wire whatever microphone he has available to 
the Elecraft pinout - I have several mics of various brands, and many 
are wired for the Elecraft pinout.

73,
Don W3FPR

ab2tc wrote:
> Hi all,
>
> This is getting more and more confusing. What exactly is the compatibility
> issue with the K3 and an electret microphone wired for Kenwood? I have a
> Heil Proset with the IC element (which is electret). I originally ordered it
> with the ICOM adapter and used it successfully for years with the IC-718.
> Prior to receiving the K3, I ordered the Kenwood cable adapter. When I got
> the K3, I plugged the mic in, set the mic selection to FP.L with bias on and
> everything seems to be working fine. I never had a K2 so I don't know what's
> up with "the K2 wiring for the Kenwood microphone". Can we please leave the
> K2 out of the picture and make a problem statement what might be the issue
> with an electret microphone intended to be used with Kenwood when applied to
> the K3.
>
> Knut - AB2TC
>
>
> Don Wilhelm wrote:
>   
>> Paul and all,
>>
>> That statement *is* true - however it may be misleading for those not 
>> familiar with the K2 wiring for the Kenwood microphone.  Pins 5 and 6 
>> are *not* wired to the microphone configuration header in the K2 for a 
>> Kenwood microphone (except for those Kenwood microphones which have an 
>> amplifier or an electret element).
>>
>> <snip>
>>
>>     
>
>