[ICOM] Icom Microphones/Levels

[Gary Fiber]

The HM-7 will be too HOT it is amplified for the older Icom's like the 
IC-720, 730, 740 which used more amplification than your current rigs do.
The SM-8 also has a lot of gain even when on the low level setting. I 
supported these products for 11 years and I sure did not know what all 
Icom users know...
I used to run my IC-730 mic gain at 9:00 and the speech processor on and 
always received good audio reports from it.
FM will almost take care of its self since the deviation is the key, but 
you can still be loud with the audio from the mic.
My best suggestion is get a trusted operator to listen to you using your 
SM-8 on the rigs of choice and talk you through the set up , make some 
notes.
I would try to leave the actual SM-8 gain at some setting like 9:00 or 
so and utilize the radio mic gain for control. Make a note what sounded 
like you to your friend.
Here lies the trouble several gain settings, which one to use, which one 
is correct. On SSB keeping with in the ALC range as instructed by the 
manual is also a guide.
Of course FM the ALC meter is not used.
I hope some of this helps.

Gary K8IZ

On 2/6/2010 8:09 PM, Rich Arthur wrote:
> I'm a bit confused...
>
> I have a IC-271A, 471A, 745, 2ea 751A's
>
> I have used, mostly, SM-6 desk Mikes, with good results.
>
> I hooked up a SM-8   to my 271/471 set up...with switches
> on rear to "L" and Mic gain to 1/2.
>
> With the Mike Gain Knob on the 471A set at Mid Point I was
> swamping (too hot) the repeater...
>
> (Be advised that the 471 just back from MTS who reset the
> deviation to 3.5...down from a 7)
>
> I was "advised" that one should set the Mic Gain on Icoms
> to 1 for FM and higher for SSB on a 271 or 471...a fact that
> all Icom users are aware of...sorry...not me.
>
> I have used HM-36 hand mikes with good results...after
> adjusting the Mic Gain control "UP" from a SM-6 set-up
>
> Question...Is there a simple way to set the Mic Gain level
> without the use of a Motorola/other Test Set up?...thus far
> I have used "word-of-mouth" replies from contacted stations
>
> Question 2...will a Icom HM-7 hand mike work with a 271/471?
> (no Up/Down feature=OK...Just PTT=OK)
>
>
>
>
> Rich  Arthur   W6HI
> w6hi22 at hughes.net
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