Astroplane with 1/4 wave top?

[SuperNasty]

Hi all, I'm sure this has been covered before but there's so much info to go through I thought I'd ask here again.

Anyway the question is has anybody tried replacing the 1/8 wave capacitance loaded top section on the astroplane or CTE top one with a 1/4 wave section?

In the patent for the astroplane it mentions that this can be done making the antenna more efficient but at the expense of bandwidth. I certainly don't need 26 to 29 MHz coverage so Just wondering if it's a worthwhile modification anybody.

Thanks

 

[HomerBB]

Marconi has done this.

 

[SuperNasty]

Thanks HomerBB, yes I have found a few threads on the forum here which I am trawling through at the moment, plenty of interesting info so far to work with.

 

[Marconi]

Hi all, I'm sure this has been covered before but there's so much info to go through I thought I'd ask here again.

Anyway the question is has anybody tried replacing the 1/8 wave capacitance loaded top section on the astroplane or CTE top one with a 1/4 wave section?

In the patent for the astroplane it mentions that this can be done making the antenna more efficient but at the expense of bandwidth. I certainly don't need 26 to 29 MHz coverage so Just wondering if it's a worthwhile modification anybody.

Thanks

Check out this thread: http://www.worldwidedx.com/cb-antennas/99050-marconi-comparing-new-top-one-vs-old-top-one.html

 

[SuperNasty]

Hi marconi, thanks for that link and the info of all your work, that's exactly what I was looking for, it's 12.30am here now so i'll go through it in detail tomorrow when I'm fresher!