I don't know about your specific model, but one icom I use to have used 
that so you could use a separate receive antenna if you wished.
73
Butch Bussen
wa0vjr
open Node 3148
Las Vegas


On Wed, 8 
Jul 2009, John Miller wrote:

> All the older icoms have that setup with the RCA jacks, I don't know what it
> is but the bolt below it is the grounding hookup.
> ----- Original Message -----
> From: "Gery Gaubert" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, July 08, 2009 10:25 AM
> Subject: hf interference news
>
>
>> Thanks to all who answered.  This is a really great list full of great
>> peop=
>> le who are willing to help.  Thanks for that first.  A little more info on
>> =
>> the grounding issue
>> The pool pump is off, all computers and the fridge is off. The ac unit got
>> =
>> turned off for a few minutes for the experiment and still static is there.
>> =
>> At least on the lower bands.  I have parts of 40 meter band with the
>> stati=
>> c and including that and lower seem to be effected.  Now for any one who
>> ma=
>> y have this radio or can figure out what I am talking about since they are
>> =
>> quite knowledgable.
>> On the back of the icom 751A  when I am looking at the front of it, I
>> reach=
>> around the right side I found a ground.  It is a bolt with a nut.  To my
>> s=
>> urprise right above this I found 3 sets of jacks that feel like they are
>> rc=
>> a plugs.  There are 6 total but it looks as if the middle 2 are in use.
>> Th=
>> ere is a wire with an rca plug on each end that goes from 1 jack to
>> another=
>> .  The wire between the 2 plugs is really short.  Any idea or better
>> explan=
>> ations, please let me know.  I am so confused now.
>
>