= = = "Pierre Vachon" wrote in message
= = = ...

Hi there, I am trying to build a longwire antenna for use in the 20 meter
band to 70 meter band area. I was looking for advice on what materials to
use for the antenna and the lead in lines. I will hook it up to a Drake r8B
radio. What is the minimum height it has to be? Where to ground it?.
Actually, does it have to be grounded if the radio is grounded at the
outlet?

I am a little limited in space as my yard is only 75 feet long and there are
power lines at the front. I assume that they are the source of an irritating
hum on the receiver on certain frequencies.

Thanks for the help in advance.

Pierre

PV,

Your simplest 'design' would be a "Low Noise" Antenna in the
'form' of an Inverted "L" Antenna. Since you have Power Line at
the front of the Yard. Consider running your Coax Cable to the
Back-End of the Yard (Possibly a Corner?). Construct an Antenna
Support at this 'spot'. I like to us Top-Rail as a Free-Standing
Antenna Support. Next at this back-of-the-yard 'location' install
a Ground Rod. Then 'mount' a Matching Transformer on the Top
of the Ground Rod. (This is your Primary Grounding Point for
your Antenna and Ground System.) Connect the Antenna Wire Element
and Coax Cable to the Matching Transformer (Balun/MLB). Route/Run
the Antenna Wire Element 'up' to the Top of the Top Rail and
'out' toward the front yard. Near the front of the Yard find
or build a second Antenna Support. (Top Rail Again?)

Some people like "Exact Numbers". So since you mention the
70 Meter and 20 Meter Bands; consider 'cutting' your Inverted
"L" Antenna to be a Quarter Wave Length on Top-Horizontal-Arm
for your Lowest Band and a Quarter Wave Length on the
Bottom-Vertical-Leg or your Lowest Band.
* 80 Meter 1/4WL = 67 Feet Top-Horizontal-Arm
* 20 Meter 1/4WL = 18 Feet Bottom-Vertical-Leg
Total Length of the Antenna Wire Element = 85 Feet.

READ: Antennas - Five Things to Consider : Antenna, Balun,
Ground, Coax & Planning
http://groups.yahoo.com/group/Shortw...a/message/1544

The SWL Versions of the Inverted "L" Antennas can be any size
because they are in-fact simply Random Wire Antennas that are
'designed' to Fit the available space.
http://groups.yahoo.com/group/Shortw...nna/message/54
Inverted "L' Antenna Reading List
http://groups.yahoo.com/group/Shortw...na/message/374
'About' the Inverted "L" Antenna = http://tinyurl.com/5aw9a
'Sizing' the Inverted "L" Antenna = http://tinyurl.com/5cqf8
The 'Low Noise' Inverted "L" Antenna = http://tinyurl.com/5953c

About - TOP RAIL as a "Free Standing" Antenna Support
http://groups.yahoo.com/group/Shortw...na/message/201
http://groups.yahoo.com/group/Shortw...enna/message/3
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REMEMBER: "The Shortwave Antenna is 55.5% of the . . .
Radio/Receiver and Antenna/Ground Reception Equation"
http://groups.yahoo.com/group/Shortw...na/message/288
A Shortwave Antenna is "Equally" Important for Good Reception [.]
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iane ~ RHF
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Some Say: On A Clear Day You Can See Forever.
http://groups.yahoo.com/group/Shortw...na/message/502
I BELIEVE: On A Clear Night...
You Can Hear Forever and beyond, The Beyond !
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