[ICOM] dynamic mike

[Anders Janis SM4RNA]

Hi Jim!

I am a bit curious. Do you use VOX on your 746? On my 775 I could use the HC 
elements if I put the element very close to my mouth and used full mic gain, 
but I was not able to get the VOX to work ok. With my mod I use the HC 
elements with mic gain at 11o clock and VOX Gain at trhee o clock and it 
works good.

/Anders

----- Original Message ----- 
From: "Jim Miller" <JimMiller at STL-OnLine.Net>
To: "ICOM Reflector" <icom at mailman.qth.net>
Sent: Friday, December 08, 2006 4:30 AM
Subject: Re: [ICOM] dynamic mike


>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/
>>
>
> ----
> 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/