I Googled SommerAntennas so I could get a look at what you are writing about and
got a 'Could not be found' message for http://www.sommerantennas.com/.

In either case a LP design has many solutions for a given frequency range for
number of elements, spacing, etc. A true LPDA will operate anywhere within it's
minimum and maximum frequency range. That is: a 13.5 to 33 MHz design will
operate ANYWHERE within that range and meet published specifications for Gain,
VSWR, efficiency, without the need for ANY on tower tuning, etc. [An LP does NOT
have the 20, 17, 15, 12 and 10 meter bands!!! It has FULL coverage ANYWHERE
within it's published minimum and maximum frequencies.]

A LP design is a driven array NOT a parasitic [YAGI} design. It's major
advantage is the very broad bandwidth it covers without tuning, traps, or stubs.
It provides slightly less 'gain' than a 3 element triband Yagi. A Long John
single band YAGI will have 3 to 6 dB additional gain above a LP, but the YAGI is
band limited.

- - -



jawod wrote:

The Sommer design is stated as having "phasing line similar to log
periodic array". Am I correct in thinking that it is not a true LPA
because of different element sizing and spacing than an LPA?

If so, what is the advantage of the "LPA-like" phasing line in this case?

John
AB8O