[Elecraft] K3s: microphone connector 8V current

[Don Wilhelm]

Grant,

The MH2/MH4 mic does not use the 8 volts directly - there is a resistor 
between the 8 volt supply and the AF line,
and that is where the 10ma is used to power the electret elemant.
The 10 ma. used by the microphone has nothing to do with the total 
current available from pin 6.

73,
Don W3FPR

On 7/26/2020 8:05 PM, Grant Youngman wrote:
> I have the same question about the current available for the 8V at the mic connector.  Is it limited to 10ma, or will it actually support a somewhat higher continuous current draw safely.  Not just for the k3, but also the K4.
>
> Grant NQ5T
>
>
>> On Jul 26, 2020, at 7:46 PM, Don Wilhelm <donwilh at embarqmail.com> wrote:
>>
>> Henk,
>>
>> If indeed it is for a mic preamp, then try it without the preamp.  The K3S has 2 stages of mic AF gain.  Normal for the usual ham mics, and a Hi level for low gain mic elements.
>>
>> You must turn on bias to have the 8 volts appear at the mic jack.  Do not use with direct connection of a dynamic mic - it makes the mic 'sound funny'.
>>
>> 73,
>> Don W3FPR
>>
>> On 7/26/2020 5:40 PM, Nr4c wrote:
>>> What are you going to use this  voltage for? I think it’s for a mic preamp. It is not the source of bias for an electret mic. That comes on the mic pin when turned On in the menu.
>> ______________________________________________________________