Re the inquiry about antenna tuners:
For about ten years I used with success a tuner manufactured by MFJ
called the MFJ-949E Versa Tuner II which uses a switched inductor and is
rated at 300 watts. Since the inductor is switched and not rotary it is
not always possible to get SWR of 1:1, but it has always been at least
2:1 or better. Due to it's small size, approximately the size of a
KENWOOD TS-440S, I have taken it on a series of semi-DXpeditions and
have had success matching a variety of antennas. I should point out
that I have owned four of these at various times and in various places
and always with consistent results. I still own one and will keep it.
At $150 list price it works. I probably should have been happy with it
and not gone further.
Two years ago when I owned a linear I purchased a MFJ-989C Versa Tuner V
which reportedly handles 3 KW PEP. This tuner features a roller
inductor and did allow me to achieve an SWR of 1:1. I sold it about a
year ago about the same time I sold the linear; it worked as
advertised. 100 watts is sufficient for my needs now. :>)
Now I was back to a 949E without the rotary inductor, and I longed for
being able to tune to 1:1 SWR. So I bought a MFJ-969 Roller Inductor
Tuner rated for 300 watts priced at $190 list. This did allow me to
tune to a 1:1 SWR, but the inductor slipped and resettability (a must
for contests) was near NIL. (This was after I straightened out the
plates on a variable capacitor in the tuner which were shorted. Yes, it
DID have a quality control sticker on it.) I talked several times with
Richard Stubbs who is evidently Martin Jue's "right-hand man" for
solving problems. He immediately said, "send it back for a
replacement". Since I had already straightened the plates I at first
said no, but in mid-December since the inductor was slipping I told him
that I'd like to pay the differance and upgrade to a unit rated at a KW,
the MFJ-962D, at $270 list but much smaller in physical size than the
989C. I did upgrade, it was shipped via UPS during the Christmas rush,
and it arrived damaged. Part of the reason for the damage, in my
non-expert opinion, was that it was NOT packaged properly. In addition,
the "quality" was once again missing, as there was a 1/2" piece of bare
wire as well as some other "crap" floating around inside the unit; I did
not relate this to Richard, but simply asked for a replacement which was
finally shipped in late January. This unit works fine, appears not to
have the slipping problem, and certainly will NOT have any problem with
the power which I am pushing into it. Yes, the SWR is 1:1 with five
differant antennas: a Cushcraft A3S tribander, a Cushcraft R5 5-band
vertical, an 80-meter Gladiator vertical with 4 full-size elevated
radials (performs super on 40 meters), a 40 meter sloper, and a 80 meter
Carolina Windom. Yes, I am happy, but as you can see it did have a
price.
Why did I not homebrew a tuner? I have done so it the past, and I
probably should have done so here. Poor eyesight is the primary
reason. Or perhaps I should have investigated other commercial tuners.
(Good results with other MFJ products probably swayed me in this
decision, and certainly will in the future!) Does a rotary inductor
make a differance? Yes, I think so, but let the experts relate how much
degradation would result from 2:1 instead of 1:1 SWR with 100 watts into
the tuner using mediocre antennas. Replies, please; would the
differance on the receiving end even be noticed?
73, Bob - W1VXV
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