[ICOM] IC-781 problem

[Steve]

Hi Hsu!

I figured out what you were asking but I'm sorry I don't have an 
answer.  I only have an R9000 receiver here and I've seen the "thorn" 
in it's spectrum mode before but mine cleared itself or perhaps I had 
some locally generated noise that was getting into the front end even 
with a shorted antenna.
Have you checked for that?  Does the "thorn" move as you tune or does 
it remain fixed in the spectrum display?

Good luck finding a cure and glad it is not serious!

Steve

At 10:04 PM 7/2/2011, you wrote:
>Thanks Steve!
>   It is correct! Sorry for my bad English!
>      My 781 seems have noise input from antenna, but I had shorted 
> the antenna.But the receiver seems are OK.I seldom use 781,main TRX 
> is IC-765,When I  operated 781  last week, I found this problem.
>
>                  73!Hsu
>----- Original Message -----
>From: "Steve" <aaaaaazcdf23 at hotmail.com>
>To: "ICOM Reflector" <icom at mailman.qth.net>
>Sent: Sunday, July 03, 2011 10:33 AM
>Subject: Re: [ICOM] IC-781 problem
>
>
> >I think it means he sees a thorn shaped waveform in the spectrum
> > scope display even with a shorted antenna input.
> > This tells me something in the scope circuit has an issue but I do
> > not have an answer on how to fix.
> >
> > This is how I read the OP's post anyway!
> >
> >
> >
> > At 09:27 PM 7/2/2011, you wrote:
> >>HUH?
> >>
> >>On Sat, Jul 2, 2011 at 4:22 PM, Hsu <hsu4qro at gmail.com> wrote:
> >>
> >> > I use an IC781 for abt 3 years, I found it have a problem,there are some
> >> > "thorn" the bottom  of spectrum scope,even I shorted the 
> antenna to ground.
> >> >   Any suggestion? Thanks in advance!
> >> >      73!Hsu
> >> >
> >> > ----
> >> > Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
> >> > Icom Users Net: Sundays, 1700Z, 14.316 MHz
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> >>
> >>
>----
>Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
>Icom Users Net: Sundays, 1700Z, 14.316 MHz
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