Below...
> On Thursday, Mar 8, 2012, at Thursday, 12:14 PM, Gary Hinson wrote:
>
> > ... and thank YOU Jim for your encouraging words. I do have the space
> for
> > several quadrillion radials but not the energy to cut them all into the
> > ground below sheep/cattle/deer foot level. So I'm w
On Thu, 8 Mar 2012, Tony Estep wrote:
> On Thu, Mar 8, 2012 at 10:54 AM, WILLIS COOKE wrote:
>> I wouldn't have mentioned it Jim, except Tony's funny comment muddied the
>> water...
> ===
> Yeah, there's always some smart-aleck to confuse the issue. But
> seriously, I don't see why MFJ c
Gary,
My L wire started out from the formula L (ft) = 234 / f (mHz). Wasn't quite
long enough and wound up adding a couple feet to it. But first, we had to get
to a zero reactance spot, and that meant (for my installation) adding two feet
to the total wire length of the FCP, as compared to what
I think you will find the original designer was Tom Rauch W8JI.
73,
Don W3FPR
On 3/8/2012 2:15 PM, Ian Wilson wrote:
> So I think that the original designer made a reasonable tradeoff. I wonder
> who that was - the design was purchased by MFJ from Vectronics, I think).
>
>
___
Tony,
There is more to it than just putting a + or - sign on the display. The
instrument must have adequate measurements starting at the front end
reflectometer to determine the sign of the reactance. The MFJ does not
have that.
If there were a microprocessor in the instrument, and it had th
The basic bridge in the MFJ - and lots of other impedance analyzers - is
insensitive to the sign of the reactive impedance. You can figure it out by
making a "small" change in frequency and seeing whether the reactance
increases or decreases. However, this takes additional software in the uP,
incre
On Thu, Mar 8, 2012 at 10:54 AM, WILLIS COOKE wrote:
> I wouldn't have mentioned it Jim, except Tony's funny comment muddied the
> water...
===
Yeah, there's always some smart-aleck to confuse the issue. But
seriously, I don't see why MFJ couldn't put a minus sign or something
on the disp
The feed point is at exactly the same elevation as the FCP - just around five
feet off the ground. The FCP should have been eight feet high, but that would
put it in the neighbor's cross-hairs and we live in a CC&R / HOA area, so
stealth is best for me. The isolation transformer unit is loosely
om: Jim Bennett
To: Elecraft Reflector
Sent: Thursday, March 8, 2012 10:44 AM
Subject: Re: [Elecraft] OT: Need Antenna Tuning Help
I stand corrected. I should have said that it simply shows numbers and it is up
to the user to figure out the correct polarity. Thanks for the input.
> I think the
x27;Cookie' Cooke
> K5EWJ & Trustee N5BPS, USS Cavalla, USS Stewart
>
>
>
> From: Tony Estep
> To: elecraft@mailman.qth.net
> Sent: Thursday, March 8, 2012 9:07 AM
> Subject: Re: [Elecraft] OT: Need Antenna Tuning Help
>
! I love this kind of dialog! 73!
Willis 'Cookie' Cooke
K5EWJ & Trustee N5BPS, USS Cavalla, USS Stewart
From: Jim Bennett
To: elecraft@mailman.qth.net
Sent: Thursday, March 8, 2012 2:19 AM
Subject: Re: [Elecraft] OT: Need Antenna Tuning Help
F
t;One must have a head" or better "One
needs a brain!"
Willis 'Cookie' Cooke
K5EWJ & Trustee N5BPS, USS Cavalla, USS Stewart
From: Tony Estep
To: elecraft@mailman.qth.net
Sent: Thursday, March 8, 2012 9:07 AM
Subject: Re: [Ele
On Thu, Mar 8, 2012 at 2:19 AM, Jim Bennett wrote:
>... the MFJ-259B does NOT show minus reactance
===
Gee whiz! That's pretty lame. As my favorite soccer announcer says
when a guy misses from short range, "Me pongo las manos en la cabeza."
Tony KT0NY
--
http://www.isb.edu/faculty/
Folks - back on the 28th of Feb I started this thread, looking for assistance
getting the K2AV Folded CounterPoise (FCP) to work on my 80 meter Inverted L
antenna. Got several good suggestions and wound up having a long series of
off-line email exchanges with Guy, K2AV. With his help, we got th
The original poster and I have a significant thread going off reflector,
and have been dealing with the tuning issues. A quarter-wave-ish wire over
an FCP and an isolation transformer is a complex, dual tuned impedance. It
sometimes does NOT prune simple like a dipole. We don't have a lot of
exp
I think you have to identify which of the two resonances is due to the
antenna and not due to the antenna + feedline. Elevated radials that
exhibit resonances of their own can also be confounding.
The multiple resonance may be due to a fortunate length of coax that
presents a 50 ohm at the sha
Guess FCP as a concept has hit the big time if it's being bandied on
Elecraft reflector. :>)
We do not have much feedback from 80 meter use at all. It's been 99.9%
about 160 meters where the huge space crunch hurts the worst.
You DO need to do all the measuring at the output of the isolation
t
Jim,
I did a little chatting with Guy K2AV when he was starting to work on
that project (W0UCE lives only a few miles from me), and I recall that
changing the height above ground changed the behavior.
So if you do not have the lowest wire 8 feet above the ground, it will
not be tuned properly.
Well, crud - my fat fingers messed up the original post. That reading at 3.654
should have been R=50, X=1, SWR=1.0. I'll take the MFJ out to the antenna base
and see what I get.
On Tuesday, Feb 28, 2012, at Tuesday, 3:43 PM, Fred Jensen wrote:
> On 2/28/2012 2:22 PM, Jim Bennett wrote:
>
>>
On 2/28/2012 2:22 PM, Jim Bennett wrote:
>
> I get TWO SWR
> nulls. Yes, two. One is at 3.461 and has R=35, X-0, and SWR of 1.3.
> The second null is at 3.654, R=0, X=1, SWR=1.0.
You have something seriously wrong, 0+j1 ohms is a short circuit, or
extremely close to one. I'm sure the SWR readin
et] On Behalf Of Jim Bennett
Sent: Tuesday, February 28, 2012 2:23 PM
To: Elecraft@mailman.qth.net
Subject: [Elecraft] OT: Need Antenna Tuning Help
I've got a K3 and a three month old KPA500. Trying to get 5BWAS; 80 meters
is my biggest hurdle. I put up an 80 meter Inverted L several months ago -
pr
I've got a K3 and a three month old KPA500. Trying to get 5BWAS; 80 meters is
my biggest hurdle. I put up an 80 meter Inverted L several months ago - prior
to getting the KPA500. The vertical part of the antenna is 40 feet in length. I
had been using two radials, about 14 inches above ground - s
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