[Elecraft] K3 low PEP Power on SSB

Wed Apr 30 01:22:20 EDT 2008

> 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.

All Kenwood branded microphones with electret elements or amplified 
dynamic elements (MC-55, MC-60A, MC-80 and MC-85) require DC on pin 
5 or the use of batteries.  The mic audio line includes a blocking 
capacitor to prevent the use of bias on the mic.  

Of all the Kenwood "desk mics" only the MC-60 (not the MC-60A) and 
MC-90 are suitable for use without modification.  The MC-60 and 90 
use an unamplified dynamic element that requires no bias or preamp 
power. 

Of the "hand mics," the MC-42, MC-43, and MC-47 are dynamic mics 
that are compatible with Elecraft K2/K3 without modification.  

73, 

   ... Joe, W4TV 

> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Don Wilhelm
> Sent: Tuesday, April 29, 2008 8:59 PM
> To: ab2tc
> Cc: elecraft at mailman.qth.net
> Subject: Re: [Elecraft] K3 low PEP Power on SSB
> 
> 
> 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/i
> ndex.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>
> >>
> >>     
> >
> >   
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