RadioBanter - View Single Post - LOG-PER: PCB-layout of LOG-PER by WA5VJB ?

March 8th 04, 03:51 PM

(Fractenna) wrote in
:

G'day everyone,

(first post on this group)

Awhile ago, I came across a log-periodic antenna (sold by Ramsey
Electronics) for the UHF-range (900-2600 MHz). It was a PCB, with the
shape of a log-per etched in copper. The design was by WA5VJB (Kent
Britain, judging from the 'hits' on google ?)

Anyway, I'm planning on building such an antenna, but can't seem to
find the pcb-layout. Is this because it's 'proprietary' ? (at least
many other Ramsey products are public, like their Doppler RDF, which
is exactly as described in QST).

So, does anyone have a PCB layout for these antenna's (there are 2
designs, for different freq.ranges)? Or, if they're on the net, does
anyone know where? I can't seem to find them...

(or, has anyone built one/bought one, and is it worth the trouble of
making one? Gain of a log-per isn't very high, and a Dipole is quickly
made...)

73,

Peter Dingemans,
The Netherlands.

Hi Peter,

The layout is a standard LPDA with a shorting stub. The stub is a via
with a 2mm half loop: this prevents the back elements from being
resonant at the higher freqs.

His son Kyle sells them on e-bay at a very reasonable price. Not hard
to find. Cheaper than you can make'em:-)

73,
Chip N1IR

I bought one some time ago and I am happy with it !

Sam