[R-390] Positive ground (slightly off topic)

[Jim Brannigan]

Bill has a good idea, but perhaps you should re-think the installation.
One stray wire and there goes the radio and perhaps some of the auto
electrics.
Jim
> How about coupling with large value capacitors (0.005, 0.01 mfd)?
Transmit
> Mica caps should do the trick.  You should also "ground" your rig with
> similar caps.  I am assuming your rig is insulated from the automobile
> chassis due to reverse polarity (positive ground).
>
> 73 de Bill, AB6MT
> billsmith@ispwest.com
>
> > Hello all:
> >
> > Given the pool of technical knowledge on this list, I wonder if anyone
can
> > suggest a way to feed a typical HF mobile whip antenna (center loaded,
> with
> > low-Z feedpoint) in an installation where the car's electrical system
uses
> a
> > positive ground.
> >
> > I tried feeding a Hustler whip through a homemade toroidal coupling
> > transformer in order to achieve DC isolation, but my transformer seems
> > inadequate to achieve adequate coupling. I'm not interested in reversing
> the
> > vintage car's system polarity. The transceiver is an Atlas-210X.
> >
> > Any thoughts?
> >
> > Vy 73, AI2Q, Alex   .-.-.