One consideration often forgotten in the dB arguement is the benefit on the
RECEIVE side as well. I would rather have 100W into a 3el yagi than 1000W into
a dipole in most cases. Then there is the antenna pattern noise/QRM rejection
as another plus.
Arne N7KA
-------------- Original message --------------
From: "D. Scott MacKenzie" <kb0fhp@comcast.net>
> As I recall - every 3 db is a doubling of power - SO:
>
> 50 watts into 11 dbd antenna - 630 watts
>
> 100 watts into 8 dbd antenna - 631 watts...
>
>
> OK - they are about equal...now what about maintenance, cost of antenna,
> etc. The 11db antenna would probably have a sharper pattern, and require a
> larger rotator. But then there is the cost of the amp, etc.
>
> At this point - it is probably just an economic decision, as well as a
> "hassle" question - which is the least hassle to set up and maintain.....
>
> Scott, aka KB0FHP
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com]On Behalf Of Randy Molyneaux
> (ve5 rjm)
> Sent: Friday, January 05, 2007 8:12 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] High Power / Low Power ? / better antenna
>
>
> I was curiously seeking info on a new repeater and came across many sites,
> and formulas
> and one in choosing the best overall system for the cost. What would it
> be.....
>
> Let's say in choosing equipment everything is fairly close in camparison.
> 50 Watts (100 % duty cycle)
> Let's not disucss options...especially right now?
> 145 feet of 1/2" coax line...(Minimum loss)
> the question is?
>
> Would you consider an amplifier pushing out 100 Watts at 100 % duty cycle
> over a 4 bay dipole antenna (8 dbd gain)
>
> or
>
> Would you consider 50 watts over a 8 bay dipole antenna (11 dbd gain)
>
> overall the area within an 60 mile radius is faily flat.
>
> All suggestions are welcome
>
>
>
> 73's
> Randy Molyneaux(VE5RJM)
> Michelle Molyneaux (VE5MDM)
> EchoIRLP Node 1710 & 1858
> EchoLink Node 48431
> ve5rjm@hotmail.com
> http://parc.sasktelwebsite.net
> _______________________________________________
>
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>
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>
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