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Re: [Amps] The ongoing 4CX250B verbage!

To: "'Ian White GM3SEK'" <gm3sek@ifwtech.co.uk>,<amps@contesting.com>
Subject: Re: [Amps] The ongoing 4CX250B verbage!
From: "Gary Schafer" <garyschafer@comcast.net>
Reply-to: garyschafer@comcast.net
Date: Tue, 4 Apr 2006 12:48:04 -0400
List-post: <mailto:amps@contesting.com>

> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
> Behalf Of Ian White GM3SEK


> By changing to the common US convention of "dB below PEP", that figure
> instantly "improves" to -36dB  :-)

I wish all would stay with your convention (the proper way) of dB below a
single tone of two tones when expressing IMD. :>)

After all, even if you note that the IMD figure is below PEP, it is still
incorrect because only one product (1/2) of the IMD is being related to PEP.

PEP is the result of the sum of two tones or carriers. 
If for example 3rd order IMD is to be referenced to PEP it should include
the sum of both 3rd order products, the sum and difference products and not
just one of those as is commonly done. That would give the same difference
as the proper way "dB below a single tone of two tones".

Bill Orr states this in his handbook.

73
Gary  K4FMX


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