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CW May 9th 04 08:44 PM

Take a look on my website. www.kc7nod.20m.com

"Drifter" wrote in message
...
Steve, if i were to mount something like that,
and bring it to the radio by coax; how would
this be grounded for static and lighting?
i would rather ground outside and not at the
radio...thanks...
Drifter...




Drifter May 9th 04 10:25 PM

just re-read you web page. good info by the way. also
looked at the 20m site. 9-1 seems to be the way to go.
i 'll try making one of these. don't have the junk box
i had as a youngster, (had my ticket in the 50's). used
my Dad's radios, never had my own set-up and never seemed
to get the time to get back into it. after my wife died, i
moved farther into the country. quiet out here. and, i got
about an acre here, should be lots of room to run wire.
i had looked at an alpha-delta. thought i'd try to brew
my own. been using a an-lp1 here. want to get outside now.
picked up 2 RS long wires and stranded 18 for a song and
a danced at a local winter fest. Breezshooters fest next
month, should find the rest of parts and a mini box. will
give it a go. i feel 55 is still young enough to fall off
a roof. you recommend long wire or something like an
inverted V? thanks a lot Steve...
Drifer...

N8KDV May 9th 04 10:29 PM



Drifter wrote:

just re-read you web page. good info by the way. also
looked at the 20m site. 9-1 seems to be the way to go.
i 'll try making one of these. don't have the junk box
i had as a youngster, (had my ticket in the 50's). used
my Dad's radios, never had my own set-up and never seemed
to get the time to get back into it. after my wife died, i
moved farther into the country. quiet out here. and, i got
about an acre here, should be lots of room to run wire.
i had looked at an alpha-delta. thought i'd try to brew
my own. been using a an-lp1 here. want to get outside now.
picked up 2 RS long wires and stranded 18 for a song and
a danced at a local winter fest. Breezshooters fest next
month, should find the rest of parts and a mini box. will
give it a go. i feel 55 is still young enough to fall off
a roof. you recommend long wire or something like an
inverted V? thanks a lot Steve...
Drifer...


I've found that around 70' or so works pretty well for all 'round use.
Start going longer and the antenna starts to get more directional with
respect to the direction the wire is running.

Gotta go! The boomers are moving in again!

http://www.weatherunderground.com/ra...olland%2c%20MI

Steve
Holland, MI
Drake R7, R8 and R8B

http://www.iserv.net/~n8kdv/dxpage.htm



Volker Tonn May 9th 04 10:57 PM



Drifter schrieb:

Steve, if i were to mount something like that,
and bring it to the radio by coax; how would
this be grounded for static and lighting?
i would rather ground outside and not at the
radio...thanks...
Drifter...


Be aware that grounding does not save your radio from a lightning shock
hitting your antenna. It will for some chance only prevent to burn down
your house. ALL electronical stuff in your house may be dead then.


CW May 9th 04 11:21 PM

If done right is does.

"Volker Tonn" wrote in message
...


Drifter schrieb:

Steve, if i were to mount something like that,
and bring it to the radio by coax; how would
this be grounded for static and lighting?
i would rather ground outside and not at the
radio...thanks...
Drifter...


Be aware that grounding does not save your radio from a lightning shock
hitting your antenna. It will for some chance only prevent to burn down
your house. ALL electronical stuff in your house may be dead then.




Drifter May 9th 04 11:40 PM

thanks Steve...
Drifter...

Volker Tonn May 9th 04 11:44 PM



CW schrieb:

"Volker Tonn" wrote in message
...


Drifter schrieb:


Steve, if i were to mount something like that,
and bring it to the radio by coax; how would
this be grounded for static and lighting?
i would rather ground outside and not at the
radio...thanks...
Drifter...


Be aware that grounding does not save your radio from a lightning shock
hitting your antenna. It will for some chance only prevent to burn down
your house. ALL electronical stuff in your house may be dead then.


If done right is does.


But for sure you can not do it by yourself and it will cost a LOT. And
at least there is NO insurance it will work under ALL circumstances.
Best (additional) way to go is to disconnect the antenna when leaving
the shack or lightning is coming up whilst you are in your shack.

PS: Quoting corrected.


RHF May 10th 04 01:34 AM

DRIFTER,

Read these three Links 'presented' by John Doty:
[ Hosted by The Association of North American Radio Clubs "ANARC".]

Longwire Impedance Matching. {Check-Out the Graphs}
http://www.anarc.org/naswa/badx/ante..._longwire.html
Actually, a fixed Matching Transformer can dramatically reduce the
wild swings in Antenna Efficiency that a Coax Fed Wire Antenna exhibits.

Grounding is the KEY to Good Reception
http://www.anarc.org/naswa/badx/antennas/grounding.html

Low Noise Antenna Connection
http://www.anarc.org/naswa/badx/ante...e_antenna.html

iane ~ RHF
..
..
= = = Drifter wrote in message
= = = ...
Steve, if i were to mount something like that,
and bring it to the radio by coax; how would
this be grounded for static and lighting?
i would rather ground outside and not at the
radio...thanks...
Drifter...

..

Drifter May 10th 04 01:55 AM

RHF. vary good reading...
thanks...
Drifter...

Frank Dresser May 10th 04 02:33 AM


"-=jd=-" wrote in message
...

[snip]

The one thing that I would like to do is try to figure out the actual
characteristic impedance of the antenna. I've found information that shows
me how to do this with a noise-bridge, but I don't have one of those.

I was wondering if anyone knows of a link or a formula for finding a
relatively close "ballpark" figure for characteristic impedance. I'm
thinking there isn't (without the inclusion of one or more physical
measurements) due to all of the variables involved.

[snip]

Reg Edwards has an interesting webpage:

http://www.btinternet.com/~g4fgq.regp/

He has many rather complicated formulas written into easy to use programs.
One of the RJELOOP programs might be helpful:

http://www.btinternet.com/~g4fgq.regp/page3.html#S301"

Be aware that the impedance will vary considerably with frequency, and will
have a large reactive component at most frequencies.

Aside from a noise bridge, MFJ sells some antenna analyzers, if you want to
spend the money:

http://www.mfjenterprises.com/products.php?catid=49

The ARRL Antenna book is a good reference. The Radio Amateur's Handbook has
less antenna info than their Antenna Book, but it may be available in your
public library.

LB Cebik has a tremendous amount of antenna info on his website. Loops(and
most everything else) are the

http://www.cebik.com/gup/groundup.html

http://www.cebik.com/radio.html

A grid dip meter is a cheap antenna toy. It is a metered oscillator which
can determine the resonant points of circuits. I got mine for about $15.
If you get one, be sure you get the coils!

I last used my grid dip meter to cut a perfectly resonant twin lead folded
dipole at 162 MHz. The perfectly resonant folded dipole worked about as
well as a meter test lead clipped to the antenna terminal. That's the way
it often goes with receiving antennas. The radios aren't usually very fussy
..

Sometimes the best approach for receiving antennas is to just string some
wire, play with transformers and experiment.

Frank Dresser




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