I'm sorry to see that QST's article review process still isn't working.

Roy Lewallen, W7EL

Heck Roy, if it worked, Nov-Dec QEX would have been 14 pages shorter. (And a
better rag for it as well!)

W4ZCB

On Mon, 18 Feb 2008 19:31:00 -0800, Roy Lewallen
wrote:

Putting the balun the input has the disadvantage of
making the tuner chassis hot.

Roy,

Thanks for ANOTHER lesson. I have a SGC-230 tuner in the RV that I
use to tune a wire when we go camping. I think the metal mounting
brackets are isolated from the floating tuner chassis and that you
have to use a grounding lug on the bottom. Never verified that since
I have always used the ground lug anyway. I was thinking of adding
ferrites to the input side of the tuner and then using it to tune a
dipole fed with 450 ohm window line. Maybe I'll just stick with the
longwire.

I noticed the guy who wrote that article mounted his tuner on an el
cheapo cutting board, probably just for that reason.

S.T.W.

Sum Ting Wong wrote:
I have a SGC-230 tuner in the RV ... I was thinking of adding
ferrites to the input side of the tuner and then using it to tune a
dipole fed with 450 ohm window line.

My SG-230 tuner manual says that is a no-no.
It says: "The coupler must be located *at the antenna*.
Never use a feed line or coaxial cable at the output
of the antenna coupler."
--
73, Cecil http://www.w5dxp.com

Sum Ting Wong wrote:
On Mon, 18 Feb 2008 19:31:00 -0800, Roy Lewallen
wrote:

Putting the balun the input has the disadvantage of
making the tuner chassis hot.

Roy,

Thanks for ANOTHER lesson. I have a SGC-230 tuner in the RV that I
use to tune a wire when we go camping. I think the metal mounting
brackets are isolated from the floating tuner chassis and that you
have to use a grounding lug on the bottom. Never verified that since
I have always used the ground lug anyway. I was thinking of adding
ferrites to the input side of the tuner and then using it to tune a
dipole fed with 450 ohm window line. Maybe I'll just stick with the
longwire.

I noticed the guy who wrote that article mounted his tuner on an el
cheapo cutting board, probably just for that reason.

S.T.W.

And you can also thank Tom Rauch, W8JI who questioned my incorrect
belief, causing me to re-think it.

Roy Lewallen, W7EL

I seem to remember an article about someone taking a full-wave
horizontal loop antenna and making two loops (or was it a half-wave
loop?). The second loop caused the antenna to match 50 ohms so it
could be fed with coax and (I think) it operated multiple bands.
Anyone remember this article and know where it might be?

Thanks
Buck
N4PGW
--
73 for now
Buck, N4PGW

www.lumpuckeroo.com

"Small - broadband - efficient: pick any two."

On Tue, 19 Feb 2008 22:55:20 -0500, Buck
wrote:

I seem to remember an article about someone taking a full-wave
horizontal loop antenna and making two loops (or was it a half-wave
loop?). The second loop caused the antenna to match 50 ohms so it
could be fed with coax and (I think) it operated multiple bands.
Anyone remember this article and know where it might be?

Hi Buck,

It is a small tuned loop (less than a tenth wave) with a smaller loop
(about a third to a fifth in size of the first loop) inside it.

Not much else to say except that polarity is vertical/horizontal when
the loops are in the horizontal/vertical plane. Make every effort to
build low Ohmic connections and elements. The capacitor will have to
stand off a high voltage (and many caps suffer from ESR).

73's
Richard Clark, KB7QHC

On Tue, 19 Feb 2008 22:44:48 -0800, Richard Clark
wrote:

On Tue, 19 Feb 2008 22:55:20 -0500, Buck
wrote:

I seem to remember an article about someone taking a full-wave
horizontal loop antenna and making two loops (or was it a half-wave
loop?). The second loop caused the antenna to match 50 ohms so it
could be fed with coax and (I think) it operated multiple bands.
Anyone remember this article and know where it might be?

Hi Buck,

It is a small tuned loop (less than a tenth wave) with a smaller loop
(about a third to a fifth in size of the first loop) inside it.

Not much else to say except that polarity is vertical/horizontal when
the loops are in the horizontal/vertical plane. Make every effort to
build low Ohmic connections and elements. The capacitor will have to
stand off a high voltage (and many caps suffer from ESR).

73's
Richard Clark, KB7QHC

The antenna article I was referring to is either full size or 1/2 size
horizontal loop and he used window line (twin-lead) wire for the loop
crossing the connection of the coax so that the wire made a continuous
loop twice going from the center conductor to the shield (he may have
used a balun, but you get the idea). This was a large loop running
around his yard.

Thanks, tho.

Buck
N4PGW
--
73 for now
Buck, N4PGW

www.lumpuckeroo.com

"Small - broadband - efficient: pick any two."