Message-ID: <XFMail.001217201811.cla.po@tiscalinet.it>
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Date: Sun, 17 Dec 2000 20:18:11 +0100 (CET)
From: "Claudio" <cla.po@tiscalinet.it>
To: rsgb_lf_group@blacksheep.org
Subject: RE: LF: Re: PSK sidebands with "slow phase changes"
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Hello Wolf and all,
I'm not shure about my idea, coming from experience in linear world BPSK
modulation, but I suggest to others my think.

BPSK modulation consist in multiplying a carrier for +1 or -1, according to
data bit to be transmitted (don't forget differential coding...).

If the carrier is injected into the first port of a four quadrant
analog multiplier end data to be transmitted (a square wave) is injected into
the other port but whith rise and falling edge smoothed with a time constant of
3 or 4 or more carrier cycles (trapezoidal wave), the output is a BPSK with slow
phase change.
My experience can't help about what happen when this signal is passed throu a
non linear (hard limiting) stage.

 73 de Claudio, ik2pii

On 13-Dec-00 DL4YHF@aol.com wrote:
> Hello Andy, Steward and others,
> 
> I also think that modifying the PSK generator with a 'slow phase change' as 
> suggested by Steward (KK7KA) is a very good idea so we don't need linear 
> transmitters / transverters for this task. I will try to program a kind of 
> "test generator" (no real PSK modulator) to see  what the spectrum looks
> like.
> Or has someone done this before so we don't have to invent the wheel twice ?
> 
> 73's Wolf (DL4YHF)
>  

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Claudio Pozzi       http://www.qsl.net/ik2pii       happy Linux user
E-Mail: Claudio <cla.po@tiscalinet.it> <ik2pii@amsat.org>
Date: 17-Dec-00   Time: 20:04:41
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