I agree with Jon's comments. I would focus on the features and reliability
between the two amplifiers together with the cost of tube replacement and
compare this with the purchase price difference.
-Paul, W9AC
-----Original Message-----
From: Jon Ogden <jono@webspun.com>
To: John Kjos <KB9RPM@centuryinter.net>; AMPS <amps@contesting.com>
To: <amps@contesting.com>
Date: Friday, March 13, 1998 5:08 PM
Subject: Re: [AMPS] Benefit
>>Is there really ant signal benefit between the AL-80B at 1000 watts or
>>the AL-1200 at 1500 watts?I can't make up my mind,am looking for some
>>opinions.Thanks John KB9RPM
>
>Well, the actual benefit is not as great as you would think or as to what
>people might have you believe.
>
>S-meters on a radio are calibrated in dB. If at 100 watts your signal is
>at S9, at 1000 Watts you would be 10 over 9 at best. 1000 watts is 10 dB
>greater than 100 watts.
>
>However, realize that everytime you double your watts, you only increase
>your signal by 3 dB. So going from 100 to 200 watts is a 3 dB increase.
>3 dB higher than 1000 watts is 2000 watts and 3 db over 2000 watts is
>4000 watts, ad naseum. This is because the dB scale is a logarithmic
>scale and not linear.
>
>1500 Watts is therfore only about 1.5 dB more power than 1000 watts.
>Going back to our signal strength example of above, a 10 over 9 signal at
>1000 watts would only be a 11.5 over 9 signal at 1500 watts, and even at
>2000 watts it would be just 13 dB over 9. Hardly noticeable.
>
>1500 Watts over 1000 Watts will NOT make a 10 dB over 9 signal a 20 dB
>over 9 signal.
>
>The only time when it might make a real difference is when you are so far
>down in the noise that the extra 1.5 dB actually brings you above the
>noise floor. Then it is a benefit.
>
>Frankly, you'd probably be better off getting a higher gain antenna.
>
>Don't get me wrong, when my amp is finished, I want it running with as
>much Pout as legally possible. You just have to realize that the benefit
>for the extra 500 watts is really not that much.
>
>73,
>
>Jon
>KE9NA
>
>
>---------------------------------------------------------------------------
>
>
>Jon Ogden
>
>jono@webspun.com
>
>www.qsl.net/ke9na
>
>
>"A life lived in fear is a life half lived."
>
>
>
>
>--
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>
--
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