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Re: [Amps] How to read the 3-500Z spec sheet?

Subject: Re: [Amps] How to read the 3-500Z spec sheet?
From: Larry <>
Date: Sun, 23 May 2010 17:28:13 -0700
List-post: <">>
On 23-May-10 4:06 PM, Joe Subich, W4TV wrote:
>   >  The beauty of 1 dB compression power is that unlike two tone testing,
>   >  absolute accuracy is not required to achieve proper operation of the
>   >  amp.
> Sure, if you end up reducing the drive by 3 dB because the user
> can't tell the difference between 1 dB compression in the amplifier
> and 1 dB of foldback in the drive due increased input SWR.

What are you talking about? How does measured power applied to the input 
jack have anything at all to do with what's going on in the exciter? I 
don't understand your point. 100 Watt carrier doesn't care if the 
exciter is in compression or folded back or standing on it's head. 100 
watt carrier is 100 watt carrier period.
>   >  You DO NOT need to know what the actual power output is, you
>   >  only need to know at what point you should be adjusting the
>   >  drive to when running a linear mode.
> You do need to know both the drive and output accurately.  That
> is the only possible way to accurately determine the gain of the
> amplifier and thus determine when the gain has dropped by 1 dB.

NO NO NO NO. You only need to know the RATIO between the output and 
input power. That's what a dB is... A RATIO  .. That's what GAIN is.... 
A RATIO.... Even an uncalibrated watt meter will give you that 
information as long as it is linear. Why do want to make this harder 
than it really is?

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