[Antennas] RE: MFJ-993B antenna tuner question

[Don Keith]

Phil:

I've been using the 993 for about seven months and have found it to be solid
in every way.  I suggest you view the reviews on eHam.net.  Most who have
posted seem to have had a good experience with the tuner.  I'm not familiar
with the other auto-tuners but understand the Palstar is a very good one.
It's just very expensive.  The LDG also seems to get mostly positive
reviews.

The 993 fits my primary need perfectly--tuning a horizontal skywire
loop--but it's also available for my other antenna experiments, using both
ladder line and coax.  My only negatives are the rather complicated menu
system and the odd way the users' manual is arranged.

I admit I have not tried any of the manual tuning features nor do I use the
true auto-tune capability.  I interface to my TS-2000 using the available
MFJ cable.  It's a bit on the pricey side, but it makes operating a snap.  I
just hit the TUN button on the rig and, if I've been to that frequency
before on the same antenna, it clicks once and is instantly below 1.5 to 1
SWR.  If it's a new frequency or I've moved some distance either side of a
memory location, it clicks away until it reaches the target match, then
remembers it for the next time.  I am only unable to get a good match with
the 993 (it throws up its two meter pointers as if surrendering) on the loop
at the very bottom of 160 and on 10 meters, but I suspect that is because of
the method I have to use to bring the ladder line into the shack and the
fact that the antenna is 470 feet long, a hundred feet short of a full
wavelength on 160.  It works fine on all other bands.  I also use the tuner
on the 150-watt setting so I have broader tuning capability.  I have not run
any more than 100 watts and don't do high-duty-cycle modes like PSK31, RTTY
or the like.  I have done some AM but my rig only emits about 30 watts in
that mode.

Results and signal reports are anecdotal, but I get very good reports on
every band, running 100 watts.  Incidentally, though I know a true balanced
tuner would be better, the 993 and its internal balun seem to handle the
balanced line quite well with no hint of heat or arcing.

You are wise to get opinions of other users and I'm sure you will make a
good purchase.  Hope your experience with whatever you choose is as good as
mine has been with the 993.

73,

Don N4KC
www.donkeith.com