Bill,
I think thats called losses, losses, losses aint it?
Best,
Will
>*********** REPLY SEPARATOR ***********
>
>On 3/9/05 at 9:05 AM Bill Fuqua wrote:
>
>>Here is the problem.
>>It seems to me that using either system effectively reduces efficiency of
>>the amplifier.
>> The Cartesian loop system modifies the input signal to linearize
>>the amplifier this changes the amplifiers efficiency. So the benefit of
>>high efficiency goes out the window when using this system with SSB.
>> The polar loop system is a variation of the DAF amplifier. We
>have
>>had lots of discussions about that here. With a method of compensating
>>for
>>phase shift due to impedance changes due to variations in the modulated
>>supply voltage. Also, I think the efficiency will also suffer at low or
>>intermediate signal levels.
>>
>>Check out:
>>
>>http://www.ece.ucdavis.edu/~spbruss/research/linearizer_methods_overview.pdf
>>
>>At 03:02 PM 3/8/2005 -0500, ToddRoberts2001@aol.com wrote:
>>>In a message dated 3/8/2005 12:48:58 PM Eastern Standard Time,
>>G3rzp@aol.com
>>>writes:
>>>How do you make them linear? Can you maintain the efficiency if you use
>>>polar or cartesian loop linearising?
>>>
>>>73
>>>
>>>Peter G3RZP
>>>
>>>I don't think it is possible to make a Class E amplifier linear in the
>way
>>>that a Class AB amplifier is linear. One practical way to use a Class E
>>>amplifier to amplify SSB is to configure it as an EER - Envelope
>>>Elimination and
>>>Restoration amplifier. Dr. Fred Raab has done much good research and
>>written
>>>several papers on the EER technique. 73 Todd WD4NGG
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>>
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