Greetings

Well I find myself to be in a rather strange delema....

A brief history to help you help me...

I was licenced in 1964...I was 16. My ham station was put in my basement..
My first antenna, a random wire, was run along the basement ceiling, out a
basement window frame, up to the eavestrough and down the backyard to the
closeline pole...About 75 feet in length...

Later, about 1972, my first 2 meter fm station the coax, rg58 or 8, when
along the ceiling, through a hole in the concrete of the house, up a tower
and to a 5 element beam...

More recently my ham station has moved up to the main floor. My 2 meter
radio is now about 6 or 7 feet above ground. I stuck a 1/4 wave length of
wire in the so239 output connector ic275a, using a right angle adapter, and,
with the mike cable extended to form one leg of a signle leg ground plane,
managed to trip a local repeater....

Now here is my situation...I would like to build a full 1/4 wave groundplane
or something similar directly above the radio but, in order to have radials
that don't pook me in the face, I will need to raise the antenna up about 2
or 3 feet. I could use coax but for that short of a run?...

Is it possible to build a length of air dialectric coax ( I am wondering
what a perfect length of coax is made of between the center conductor and
braid and how long it would have to be ), 50 ohm that is about 2 to 3 feel
long?

Next question would be.. how to tune it...

I am guessing that it is about 5 feet from the radio to the ceiling...

Any thoughts?

Larry ve3fxq

Larry,
Short lengths of coax work as well as long ones do.
Unless you just want to 'play' with home brewing some
coax, use commercially made stuff.

"larry" wrote in message
e.rogers.com...
Greetings

Well I find myself to be in a rather strange delema....

A brief history to help you help me...

I was licenced in 1964...I was 16. My ham station was put in my
basement..
My first antenna, a random wire, was run along the basement ceiling, out a
basement window frame, up to the eavestrough and down the backyard to the
closeline pole...About 75 feet in length...

Later, about 1972, my first 2 meter fm station the coax, rg58 or 8, when
along the ceiling, through a hole in the concrete of the house, up a tower
and to a 5 element beam...

More recently my ham station has moved up to the main floor. My 2 meter
radio is now about 6 or 7 feet above ground. I stuck a 1/4 wave length
of
wire in the so239 output connector ic275a, using a right angle adapter,
and,
with the mike cable extended to form one leg of a signle leg ground plane,
managed to trip a local repeater....

Now here is my situation...I would like to build a full 1/4 wave
groundplane
or something similar directly above the radio but, in order to have
radials
that don't pook me in the face, I will need to raise the antenna up about
2
or 3 feet. I could use coax but for that short of a run?...

Is it possible to build a length of air dialectric coax ( I am wondering
what a perfect length of coax is made of between the center conductor and
braid and how long it would have to be ), 50 ohm that is about 2 to 3 feel
long?

I have built short solid coax with 3/4" copper tubing and 1/4" inside copper
tubing.
Or whatever you have that come close to 138 log (ratio of the two tubings)

Next question would be.. how to tune it...

The answer is: "how do you tune ANY antenna system?".

I am guessing that it is about 5 feet from the radio to the ceiling...

Any thoughts?

Larry ve3fxq


--
*
| __O Thomas C. Sefranek
|_-\,_ Amateur Radio Operator: WA1RHP
(*)/ (*) Bicycle mobile on 145.41, 448.625 MHz

http://hamradio.cmcorp.com/inventory/Inventory.html
http://www.harvardrepeater.org