[Elecraft] Microphone question - K3

[Don Wilhelm]

You are correct that with a 3 lead electret - the V+ and the AF should 
both be corrected to pin 1.  The remaining pin of the mic element should 
connect to pin 7 or pin 8. 
Many electret elements only have 2 leads and must obtain the bias 
voltage through the AF line, apparently the one you have provides for 
separate powering.

With a 3 lead electret element, you could try connecting only the AF pin 
of the element to pin 1, and the ground to pin 7 or 8, and connect the 
V+ wire through a 10k resistor to pin 5.  If you wire it that way, you 
do not need the bias turned on (but it may not matter whether bias is on 
or off).

73,
Don W3FPR

NZ0T wrote:
> Forgive me for being dense about this!  The RS element has a red wire that is
> the V+ for the element.  The other wire is the shielded audio output wire.
> Because the K# has switchable voltage available at pin 1 and from what Lyle
> posted I assume a coupling capacitor (which allows both V+ and audio to
> coexist?) in that line my understanding was that the red V+ wire and the
> audio output wire both go to pin 1 and the shield to pin 7.  If I connect
> the audio output to pin 1 and the shield to pin 7 where do I connect the red
> V+ wire to get the voltage needed to power the element?
>
>
> Don Wilhelm-4 wrote:
>   
>> Are you saying that you connected 2 wires to pin 1?  There normally 
>> should only be one wire to pin 1, and that is the AF line which should 
>> connect the other end direct to the + side of the electret element.  The 
>> other side of the electret element must connect to ground (pin 7 or pin
>> 8).
>> Turn bias ON in the FP mic menu and likely with an electret, you can use 
>> the L setting.  In other words, the MIC SEL menu parameter should be 
>> FP.L bIAS.
>>
>> 73,
>> Don W3FPR
>>
>> NZ0T wrote:
>>     
>>> I tried a RS electret element I have here and the audio is distorted and
>>> weak
>>> - do I have a bad element or am I doing something wrong?  I wired the
>>> element directly to the mic wires bypassing the transformer in the mic
>>> with
>>> no cap or resistor.  The red wire and audio to pin 1 and the ground to
>>> pin
>>> 7.  Guess I'm clueless when it comes to electret mics!
>>>   
>>>
>>>       
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