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PA3HHO
August 31st 03, 09:56 PM
Hi OM's

Last year during a Dutch Ham fair I bought myself a Comet VA30. This is a
shortened base loaded multiband dipole for 7/21/28 MHz. The manual that was
included was Japanese. I was able to figure out the correct dimensions
(depending on how you setup the antenna e.g. as a horizontal dipole or (3
x ) vertical with one (3 x) radial per band.

The instructions about a capacitor that's supposed to be in parallel with
the feedpoint is unreadable. I know that (heavily) shortened dipoles need
some kind of adaption to get a VSWR of 1:1 @ 50 Ohm. Two caps (small ceramic
disc type, probably in 100's of pF range) are included but I'm not sure
which one to use. I've used one, the other, both and none, but VSWR is
terrible on all three bands.

I know I can't expect micacles from a 2 x 9 ft dipole on 40 meters, but I
should do OK on 15 and 10 I guess. Because of it's size it's ideal for on
holidays but last one was no success at all. Anyone has any experience with
this antenna and/or maybe has an English (German, French or Dutch OK too)
manual for the Comet VA30?!

Thanks!

Rgrds, Pleun (PA3HHO)

Tom Coates
September 1st 03, 01:59 AM
The maker might respond to an e-mail. They have a website at
http://www.comet-ant.co.jp

Tom, N3IJ


"PA3HHO" > wrote in message
...
> Hi OM's
>
> Last year during a Dutch Ham fair I bought myself a Comet VA30. This is a
> shortened base loaded multiband dipole for 7/21/28 MHz. The manual that
was
> included was Japanese. I was able to figure out the correct dimensions
> (depending on how you setup the antenna e.g. as a horizontal dipole or (3
> x ) vertical with one (3 x) radial per band.
>
> The instructions about a capacitor that's supposed to be in parallel with
> the feedpoint is unreadable. I know that (heavily) shortened dipoles need
> some kind of adaption to get a VSWR of 1:1 @ 50 Ohm. Two caps (small
ceramic
> disc type, probably in 100's of pF range) are included but I'm not sure
> which one to use. I've used one, the other, both and none, but VSWR is
> terrible on all three bands.
>
> I know I can't expect micacles from a 2 x 9 ft dipole on 40 meters, but I
> should do OK on 15 and 10 I guess. Because of it's size it's ideal for on
> holidays but last one was no success at all. Anyone has any experience
with
> this antenna and/or maybe has an English (German, French or Dutch OK too)
> manual for the Comet VA30?!
>
> Thanks!
>
> Rgrds, Pleun (PA3HHO)
>
>

PA3HHO
September 1st 03, 07:33 PM
Hi Tom,

> The maker might respond to an e-mail. They have a website at
> http://www.comet-ant.co.jp

Thanks for your reply. First thing I did (before posting a message here) was
exactly what you suggested HI.

Did not receive any reply yet unfortunately...

Thanks!

Rgrds, Pleun (PA3HHO)

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