[Antennas] MFJ 986 antenna tuner

Wed Feb 2 12:36:09 EST 2005

I know you say in your message that the tuner doesn't tune "any
antenna" on 17 meters, but how many antennas have you tried?
It might be nothing more than a difficult-to-tune impedance at the
tuner end of the transmission line. You might be able to add or
subtract a few feet of transmission line and get the tuner to work.
It's possible that the tuner couldn't tune "any antenna" because
every antenna you tried just happened to have a troublesome
impedance at the tuner end. Not likely, I know, but it's possible.
I can think of no other reason why a tuner would fail to work on
only one band, unless a previous owner added a trap or other
kind of tuned circuit to the circuit for some reason. I suppose
that RF on the outside of the line could possibly cause this kind
of behavior as well.
73,
Dave NB4J
>Alan Hughes wrote:
> > I have an MFJ986 Differential T Tuner which works very well on all bands
> > except 17 metres. For some reason it will not tune any
> > antenna to a workable SWR on this band. Has anyone else run into this
> > problem or know of a modification for it please??
> > Alan ZL3KR