40 meter dipole or 88 feet doublet
 

Hello,

As my 40 m. rotable dipole (2* 7 m. = 42 feet with coals) was damaged by the
storm I am thinking to make something different. The dipole height was at 40
feet.

I can increase the heigth with a pipe to 60 feet and make a 80m. dipole 2 *
20 m. (120 feet) Inv. V. (West/East) and a 40 meter dipole 2 * 10m ( 60
feet) or a doublet of 88 feet (South/North)? Both with ladder line.

I mainly work on 80/40 and 30 m. the other bands are nice to have.

The question is should I make the 40 m. dipole or the doublet or renew the
old rotable dipole? Or any other suggestions..

73 pa3glf

Check out w4rnl at cebik . com he is a proponent of the 88 foot doublet.

I have a 90 foot doublet, as that is what my trees provided for. An
advantage is that it is a 1/2 wave
on 60 meters so I don't have to adjust my calculations for erp on that band.

In order to tune the 90 footer which is fed by about 50 feet of 450 ohm
line, I had to make a
modification to my Johnson Matchbox. I could have altered the feed line
length, but I chose not to.

I use the doublet on 80 through 10, and it does what the models say it
should at the low hieght
(28 feet) that I have it.

Since I am not worried about directionality, I have considered going to a
132 foot dipole
when I can consider a way to suport it.
KA9CAR



"Dick" wrote in message
...
Hello,

As my 40 m. rotable dipole (2* 7 m. = 42 feet with coals) was damaged by
the
storm I am thinking to make something different. The dipole height was at
40
feet.

I can increase the heigth with a pipe to 60 feet and make a 80m. dipole 2
*
20 m. (120 feet) Inv. V. (West/East) and a 40 meter dipole 2 * 10m ( 60
feet) or a doublet of 88 feet (South/North)? Both with ladder line.

I mainly work on 80/40 and 30 m. the other bands are nice to have.

The question is should I make the 40 m. dipole or the doublet or renew the
old rotable dipole? Or any other suggestions..

73 pa3glf

"Dick" wrote in message ...
Hello,

As my 40 m. rotable dipole (2* 7 m. = 42 feet with coals) was damaged by the
storm I am thinking to make something different. The dipole height was at 40
feet.

I can increase the heigth with a pipe to 60 feet and make a 80m. dipole 2 *
20 m. (120 feet) Inv. V. (West/East) and a 40 meter dipole 2 * 10m ( 60
feet) or a doublet of 88 feet (South/North)? Both with ladder line.

I mainly work on 80/40 and 30 m. the other bands are nice to have.

The question is should I make the 40 m. dipole or the doublet or renew the
old rotable dipole? Or any other suggestions..

73 pa3glf

If it were me, I'd probably parallel 80 and 40 dipoles on the same
feedline using coax. 30 meters I would either use a tuner, or add a
30m dipole also in parallel for that band if you don't want the tuner.
If ladder line fed, it doesn't matter a whole lot, but I'd make the
dipole as close to 80m size as possible. I'd probably use a full size
80m dipole, and feed as two half waves on 40, and whatever on 30. I
prefer coax fed though. More efficient overall being you need no tuner
or matching devices. You also get a normal dipole pattern for each
band you cut a dipole for. MK