What kind of handheld rig you talking about?
----- Original Message -----
From: "Bill Fulling" <w4njf@email.midflorida.com>
To: <tentec@contesting.com>
Sent: Friday, November 14, 2003 21:47
Subject: Re: [TenTec] Orion and MIKEs
> Hi Grant,
> Have got to disagree with on this subject.Another poster noted that the DC
> resistance from the shell of the mike jack was abt 6 OHMS and asked to
> anyone else to try it-the DC reisistance on my Jupiter to the back chassis
> ground point reads abt 8 ohms.No way this should occur-if the shell is NOT
> grounded to DC potential,all kind of RFI problems will occur;pls do NOT
say
> "its an RF in the shack problem,or ur ant is too close to the rig".
> This why T/T has NEVER built a handheld rig!Its hard to say the antenna is
> too close to rig when its a handheld.Why this audio port "floats"above gnd
> is a mystery to me also.
> 73 de Bill W4NJF;A Jupiter owner with the same problem.
>
> ----- Original Message -----
> From: "Grant Youngman" <nq5t@comcast.net>
> To: <tentec@contesting.com>
> Sent: Friday, November 14, 2003 11:07 AM
> Subject: Re: [TenTec] Orion and MIKEs
>
>
> > >
> > > If you run a new ground wire (I used insulated stranded 18 Ga.) from
> > > mic pin #2 (ground) to the same board that mic connector goes to and
> > > then to the rear lug on the rig, this will eliminate the 6 ohms in the
> > > audio chain. But not in the IF and RF chain. separate lines will have
> > > to be installed to remedy that issue.
> >
> > One last comment on this bothersome subject ... no flame intended.
> >
> > The other thing you will accomplish by fiddling with this is to create
> > unwanted ground loops that may cause all manner of problems. The 6
> > ohms is not an issue. Adding is a few extra ground wires may seem
> > harmless, but destroying the signal and power ground engineering that's
> > in a complex mixed mode analog and digital device is simply not
> > advisable.
> >
> > This begs for enough trouble as far as the audio path is concerned. In
> > the RF/IF/digital sections of the radio an extra ground path or two
could
> > wreak real havoc.
> >
> > I'll go back to my original statement which is that if RF feedback is a
> > problem then the way to rectify it is to clean up the RF environment in
> the
> > radio room.
> >
> > Grant/NQ5T
> >
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>
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