In a message dated 11/15/01 7:33:34 AM Pacific Standard Time,
w8ji@akorn.net writes:<
Let's try this again. The message bounced, and I don't keep
copies, and I hate to retype the same thing twice.
The MFJ artificial ground cannot make a 1/4 wl ground lead
grounded at the far end into anything "good".
The only thing the artificial ground does is cancel reactance in the
ground lead. It will NOT make a 1/4 wl ground lead or any other
poor ground lead length look like a low impedance, because it is a
two terminal device and can't "stretch" the line.
While there are cases where it can help, there are just as many
cases where it will not help. It might do the trick in some
situations, but certainly will not in all of them.
73, Tom W8JI
W8JI@contesting.com
>>
In a message dated 11/15/01 1:14:39 PM Pacific Standard Time,
thompson@mindspring.com writes:<<
The advice from K7GCO is good. I would add that my first shack at my
present location was a second floor bedroom. The Artificial Ground
works
well. I moved to the basement and it still did a good job there. I
have
three (multiple) paths to ground but found on 10 and 17 there was a poor
enough ground for the MFJ to work. I made a good ground for both but
found
that it was best to switch the MFJ out when working the other
bands...as the
MFJ caused say 20 to be detuned. It does affect loading which in this
case
caused SWR to appear higher so my transceiver would balk (but not the
amps..so go figure).
73 Dave K4JRB
>
> In a message dated 11/14/01 7:22:58 PM Pacific Standard Time,
> aa0cy@VRINTER.NET writes:
>
> << anyone used this device, which sounds like an "antenna
> fooler" for the ground system? Good? Bad? Indifferent?
> I've got a good 35' run to where the water line enters the
> basement...
> Thanks. > 73
> Bob AA0CY
>
> Yes it works. It's a series circuit that alters the length of what
ever
> it's connected to, to a 1/4 wave (or 3/4 wave) that's a low Z path
for RF.
> I'd try hooking it to the wire to the ground, some other lengths and
the goal
> is "maximum RF cooling." The internal meter measures max RF current
just
> before the terminal you connect a wire to your rig or whatever you
want to
> cool. K7GCO
>>
Tom: No one said it worked all the time and/or without some
modifications of wire length. You say it works and then you say it doesn't
work. Which is it? Few things work every time. Just because it doesn't
work in all your cases you have to do your "TT Flame" for reasons best known
to you. I specifically suggested different lengths on it's tail end so that
it works most or all the time as the MFJ unit has some limit's in what it
does. Dave above "verifies EXACTLY what I said" and he had the ability to
try different lengths to make it work for him satisfactorily--you didn't.
I've found it cooled the chassis of a tuner one time indicating it presented
a Lo-Z to it and as indicated by the internal meter, RF current did indeed
flow typical in Low Z's. I inserted a RF Ammeter in series just to see how
much current was flowing--2 A.. Tom you will have to speak to the MFJ
Artificial Ground directly as it can't read TT about what you say it can't
do.
Dave also noticed it affected the unit it was connected to also. It's got
some "RF Hooks" in it if adjusted right. How it does it no one really give a
damn and if you approve or not. Every piece of equipment is not all bad or
are all the new ideas bad you can't understand.
Now the MFJ Artificial Ground can present a Lo-Z to what ever it's
connected to if the wire length on the tail end is fairly compatible for the
MFJ, MOST OF THE TIME. If it doesn't, change the length. The built in meter
tells you when "it's doing it's thing." It works great on "second floors" as
Dave above suggests (even the basement) and can prevent TVI on 6m--I know.
In ham radio one must be creative enough to solve "simple problems" to
accommodate practical limits of any equipment or it's not ethical to "Flame
It" anywhere. You must have a lot of technical helpers with your station
there to get things to work for you. Tom what useful purpose did your post
serve? I clearly stated it didn't work every time with certain lengths of
wire. Why was it ncessary for you to say it again and not provide a
solution--as I did?
Something that works deserves the proper recognition. I just invested over
$1000 of my own Retirement Money and a lot of time to give a FREE PLUG to
Raibeam and it's beam design (that you don't think works.) in the Dec 73 Mag.
Have you ever done that? Mfgs often invest large sums of money to market
gear. There is a lot of equipment in Ham Radio that didn't survive Critics
like you--that couldn't make it work. Many Mfgs lost big sums of money as a
result. I've got 5 E-mails telling of how the MFJ worked for them. They
didn't care for your comments either. They are going to continue to use it
regardless of your technical inability's.
The MFJ Artificial Ground like the Match Box works just fine when "properly
used"--please leave them alone or learn how to properly use them. I wish the
Artificial Ground was still made. Tom, you have this "Total Misconception
and Delusion" that every thing or new idea has to be approved by you to be
useful, worth trying or you get on your "TT RF Negative Soap Box." It's not
a W8JI Ham Radio Police State as yet but it's getting there. The rest of us
still reserve the right to use what we want although appreciate legitimate
info on equipment deficiencies. Lets support equipment that works and new
ideas even if you didn't think of them. If you need some help on how
something works, I'll be glad to help you.
Dave, I thank for your support. You get the "K7GCO Good Samaritan Award"
for "Defending What Works." I'm all alone sometimes supporting equipment and
proven ideas that work. MFJ appreciates it also. Wait until Martin F Jue
hears of this. K7GCO
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