VHFcontesting
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Re: [VHFcontesting] Log Periodic ?

To: Mark Spencer <mark@alignedsolutions.com>
Subject: Re: [VHFcontesting] Log Periodic ?
From: Jay Lubliner <ironclaw@live.com>
Date: Wed, 13 Sep 2017 22:31:00 +0000
List-post: <mailto:vhfcontesting@contesting.com>
Hi all,

I had a Creative Design LP years ago. Realizing it's a compromise both gain 
wise, only 3 elements make up the log cell per say, and limited front to back 
isolation, I present the following discussion:

In a crowded band area or lots of high power OPS nearby, it can't handle the 
overload of signals because it's collecting too much signal receive wise from 
strong stations or nearby transmitters. You can't reduce the overload or 
splatter very well by turning it somewhere else for example. Also it doesn't 
have anymore than 6db gain. Single yagis at same boom length would have more 
selectivity and gain. 
Other issue is it's not likely you have a rig with separate coax outputs for 
all the log could cover. 50, 144, 222, 432, 903, 1296. How do you switch bands? 
Coax switch? You'd need a six position or 4 positions even for lower 4 bands. 
Doable perhaps but one must pay attention to turn the knob every time you 
QSY.!!!..that gets pretty old and when you get 6 hours into contest, you forget 
and yell your brains into aluminum not currently resonant. You'll say, "where 
is that guy?...we're suppose to go to 432.1...don't hear anything!!!!
Mine was fine for sprints or casual operating and sure one feed line is nice 
but adding amps and such also gets more complicated. 
Maybe if you're very good technically you could build a relay switching box but 
every connection increases possible reliability and bug issues. You have enough 
in Rover state.

I'm sure this will stir up some chatter but just my 2 cents or 2 db's worth 
having used one.

Jay
K3JAY

Sent from my iPhone

> On Sep 13, 2017, at 4:16 PM, Mark Spencer <mark@alignedsolutions.com> wrote:
> 
> Hi:
> 
> I've used the (IIRC 105 thru 1300 MHz ?) version for several years.
> 
> I'm happy with my purchase.   That being said it is not my primary contesting 
> antenna and it stayed at home during the last contest as I didn't think it 
> had enough gain to be useful at the sites I planned on visiting (plus mine 
> didn't cover 50 MHz.)
> 
> I'm happy with the built quality of mine and it seems to have held up well to 
> traveling in the bed of my 4x4 on forest roads.   In my experience it is a 
> handy multi band antenna with some gain and directivity and I've made lots of 
> contest contacts with mine.
> 
> I'd also be curious in hearing from those who have used the version that 
> covers 50 Mhz.   I've pondered putting one up at my home qth to get a 
> horizontal antenna with a certain amount of gain on 50 MHz and up.
> 
> 73
> 
> Mark S
> VE7AFZ
> mark@alignedsolutions.com
> 604 762 4099
> 
>> On Sep 13, 2017, at 12:47 PM, Ed via VHFcontesting 
>> <vhfcontesting@contesting.com> wrote:
>> 
>> I am considering a Create LPDA for a roving station. Thinking it'll sit 
>> nicely on the roof of my fifth wheel. This would allow me to work all bands 
>> from 6m to 1.2 Ghz with a single antenna. I can also change the polarization 
>> for FM. Thoughts?  
>> 
>> 73,
>> Ed NI6S
>> _______________________________________________
>> VHFcontesting mailing list
>> VHFcontesting@contesting.com
>> http://lists.contesting.com/mailman/listinfo/vhfcontesting
>> 
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