[Elecraft] Mic Noise

[Don Wilhelm]

Buck,

The Heil Goldline mic is a dynamic type, last I heard it has an HC-5 
element.  It should have bias off.
The Elecraft MH4 is an electret type and must have bias set on - use 
"FP.L bias"

It may just be that you have too much mic gain - start with a mid-range 
setting.  The mic preamp can shut down if it receivers too much signal.

Make sure there is nothing plugged into the rear mic jack - although MIC 
SEL should allow you to switch from one to another.

If you are not successful, do you have one of the computer type 
microphones?  If so, plug it into the rear mic jack, set MIC SEL to 
"RP.L bias" and see if you get any audio.

Have you made any changes to the Front Panel assembly where you removed 
the DSP board?  If so, there is one connector between the Front Panel 
board and DSP board that if not mated properly will cause the front 
panel audio to fail.

The TX DLY should have nothing to do with it.  The KPA500 becomes active 
with very little delay.

73,
Don W3FPR

On 3/16/2019 4:24 PM, Buck wrote:
> Thanks. I was using a Heil Goldline and also tried an Elecraft MH4 
> plugged in the front.  I get the same noise on FP.L and FP.H  Bias is 
> off.  And, I still get the noise even when in TEST mode, so there is 
> no RF.
>
> I had the Tx Dly on the K3S set to 8.  I set it to 15 and the problem 
> went away.  Was I hitting the amp too soon?  Amp is a KPA500.
>
> Now the problem is back, even with the Tx Dly set to 20.
>
>
> k4ia, Buck
> K3# 101
> Honor Roll  8B DXCC
> EasyWayHamBooks.com
>
> On 3/16/2019 3:41 PM, Don Wilhelm wrote:
>> Buck,
>>
>> Which transceiver and which microphone?
>> If the K3, are you using the front panel mic jack or the jack in the 
>> back?
>> How do you have MIC SEL set?
>>
>> 73,
>> Don W3FPR
>>
>> On 3/16/2019 2:57 PM, Buck wrote:
>>> I never use a microphone so here I am today trying to run voice in 
>>> the Va QSO party.
>>>
>>> When I key the mic, I get a burst of noise that lasts maybe a half 
>>> second.  It does this even if I have the rig in "test" mode ie. no 
>>> transmit.  So, I don't think it is RF.
>>>
>