Re: Low mic gain, was, show your mic

MAX <max@...>
 

Hi sarma.

 

I’m sure I have the polarity correct.  Someone on this list posted a drawing showing how to identify the negative terminal and I wired according to it.  I think the electret mic wouldn’t work at all if polarity were reversed.  What is being powered is an  F E T source follower.   I think I shouldn’t have to raise my voice to get 5 watts output on 40 meters.

 

Regards.

 

Max K 4 O D S.

 

I've Never Lost the Wonder.

 

Antique Electronics Site: http://www.angelfire.com/electronic/funwithtubes/

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Mvs Sarma
Sent: Sunday, April 22, 2018 3:44 AM
To: BITX20@groups.io
Subject: Re: [BITX20] show your mic

 

Max,

 please check whether the mic body is connected to chasis ground.

i mean the positive bias voltage for mic should come on independent pin and NOT to the body pin of the eletret element.

In case you are using a dynamic mic, perhaps we need more gain and your need to shout appers logical.

regards

sarma

vu3zmv


Regards
MVS Sarma
 

 

On Sat, Apr 21, 2018 at 11:27 PM, MAX <max@...> wrote:

Speaking of mics, I have to raise my voice almost to the level of shouting to get 5 watts out on 40 meters.  Is this normal or should I look for a problem?

 

Regards.

 

Max K 4 O D S.

 

I've Never Lost the Wonder.

 

Antique Electronics Site: http://www.angelfire.com/electronic/funwithtubes/

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Mvs Sarma
Sent: Saturday, April 21, 2018 7:17 AM
To: BITX20@groups.io
Subject: Re: [BITX20] show your mic

 

I had grabed a taperecorder mic with 3.5mm mono pin.
 replaced the cable with 2+shield.had a small pushed switchmounted and wired.
 repalced the 3.5mm momo pin to stereo pin. Here is a image of my mic.The pp9 battery helps to imagine the mic size.
regards
 sarma
 vu3zmv

 

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