[FoxHunt] antennas for harmonic sniffing

WolfBob [email protected]
Tue, 27 Jan 2004 23:01:29 -0800


Great Dale:

The URL is not working try:

http://www.cebik.com/wb46.html
for his wide spaced 6 el. 420, I didn't find the short one.


The dimensions for my 6 el wide spaced is:

F=732.825 (146.565 X 5) wavelength= 16.106 in. 1/8 in. brass welding rod

ref    7 3/4      0
drv    7 1/16     3
1      7          6 7/8
2      6 7/8     10 3/4
3      6 7/8     14 5/8
4      7         18 1/2

At 55 inches off real ground:
Vert pol lobe 3dB=48.2 deg G=16.05 dB
Horz pol lobe 3dB=42   deg G=17.91 dB

Bob, WB6JPI



Kuon & Dale Hunt wrote:


> 
> 
>    I used the metric scale on my ruler since it was
>    a whole lot easier than trying to convert the
>    scaled element dimensions to thirty-seconds of
>    an inch.
> 
>    Element diameter 1/8" or #8 wire, insulated boom
>    Design frequency 730 MHz
>    Direct 50 ohm feed.
> 
>                     length     spacing from reflector
>                  inch     mm       inch     mm
> 
>    reflector     8.158   207
>    driver        7.957   202        2.04     52
>    dir 1         7.295   185        2.88     73
>    dir 2         7.025   178        5.21    132
>    dir 3         7.025   178        7.49    190
>    dir 4         6.690   170        10.90   277
> 
>    Note that the spacing between the driven element and
>    the first director is very small - less than 3/4".
>    Total length is under 11".  It may look a bit funny,
>    but it has a nice clean pattern and sharp lobe.  I
>    scaled this from W4RNL's "OWA" design:  design info
>    and pattern plots for other bands are available on
>    his web site at www.cebik.com/radio/
> 
>    Might be optimized further - I haven't modeled it.
> 
> 
> ---
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