I did some EZnec model comparing an 18 ft. boom T8 to an 18 ft. boom C3. The
gain is down about half to 3/4 dB on the T8, if I remember correctly. And it
covers more bands and is $400 less. I haven't compared anything larger yet.
Chris
KF7P
On Oct 25, 2013, at 11:03 AM, Joe Subich, W4TV wrote:
>
> Only a small portion of the LP elements carry significant current on
> a given frequency - only a "few" elements are "active". This means
> that the gain of an LP is generally equivalent to a non-optimum two
> element or short boom three element antenna at best. Given the limited
> number of active elements and the sub-optimal currents, side and back
> rejection are generally significantly poorer than a well designed Yagi.
>
> Log Periodic antennas provide coverage of a lot of "useless" spectrum
> at the cost of efficiency, reduced performance in the narrow amateur
> allocations and substantial mechanical complexity.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 10/25/2013 12:45 PM, Jim Brown wrote:
>> On 10/25/2013 9:38 AM, Gene Fuller wrote:
>>> Would you like to add any comments regarding LP's.
>>
>> I don't know enough about them to comment. I've only heard that their
>> gain is relatively low compared to a Yagi with the same boom length. It
>> has long been well known that the gain of a Yagi is related to boom length.
>>
>> 73, Jim K9YC
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