[ICOM] dynamic mike

[Jim Miller]

I also have Heil HC4 in my headset, HC5 and studio in my gold line that were
bought for my Kenwood 440 and use them through an adapter (pinout changer
with out any preamplifier) on the original Icom 746 and have never done any
of the mods to the Icom BUT I have to turn the mic gain all the way up to
get the gain as it would have been in a "normal" setting on the Kenwood.
Works fine that way so IMHO the mods do not really have to be done.  It does
take the gain (on my particular radio) up to where it needs to be and maybe
a bit above although other radios may not have been set exactly as mine new
from the factory.

73, Jim

----- Original Message ----- 
From: "Anders Janis SM4RNA" <sm4rna at telia.com>
To: "ICOM Reflector" <icom at mailman.qth.net>
Sent: Thursday, December 07, 2006 4:47 PM
Subject: Re: [ICOM] dynamic mike


> Gary, I just checked the schematic. The mic earth do not have a series DC
> blocking capacitor. The mic earth is directley connected to the earth of
the
> amp.
>
> Jack I have posted a mod on www.mods.dk that brings up the gain to the
same
> level as the IC-756 non PRO on a IC-775. I use my radio with Heil HC-5
with
> that mod and it works fine. Of course I use a DC blocking capacitor in
> series with the mic element.
>
> I have never tried a Astatic so I do not know if the mod will be the
> solution or not.
>
> /Anders
>
>
> ----- Original Message ----- 
> From: "Gary P. Fiber" <gfiber at clearwire.net>
> To: "ICOM Reflector" <icom at mailman.qth.net>
> Sent: Thursday, December 07, 2006 11:14 PM
> Subject: Re: [ICOM] dynamic mike
>
>
> > Jack,
> >
> > The mic amplifier gain may be an issue but further there is a simplex
> > voltage
> > applied to the mic pin, generally + 8 VDC.  Most dynamic mics I have
seen
> > are a
> > direct DC coupling from Mic input to Mic ground, there may be an issue
> > shorting
> > the +8 VDC to ground with little DC resistance.
> >
> > Some of the Icom rigs do have a capacitor in the ground  mic audio
ground
> > so it
> > is signal not DC ground but I do not remember about the IC-775. A check
of
> > the
> > schematic will tell though.
> >
> > I am sure during my time at Icom I helped a few connect up dynamic mics
> > but
> > can't remember about the low drive issue. I think Astatic makes an
> > amplified
> > base for their mics which should solve that trouble if it is one.
> >
> > Gary K8IZ
> >
> >
> >
> >> Hello All:
> >> I am new to the Icom Reflector.
> >> I would like to use a Astatic model DA dynamic mike on a IC-775-dsp
rig.
> >> I am told that there is not enough gain in the rigs preAmp for a
> >> dynamic mike.Is this correct ?
> >> ----
> >> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> >> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> >> Icom FAQ: http://www.qsl.net/icom/
> >>
> >
> >
> >
> > Gary P. Fiber K8IZ
> > GROL PG-19-6691
> > Washington State Resident
> > ----
> > Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> > Icom Users Net: Sundays, 1700Z, 14.316 MHz
> > Icom FAQ: http://www.qsl.net/icom/
>
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
>