Hello RTTY'ers,
----------
> Îò: George Johnson <w1zt@mediaone.net>
> Êîìó: Ekki <ekki@plicht.de>; _Rtty <rtty@contesting.com>; Jay
<jay@ieway.com>
> Òåìà: Re: [RTTY] Bandwidth of a RTTY signal (was:SO2R RTTY
Radio)
> Äàòà: 28 àâãóñòà 2001 ã. 23:01
>
> Jay, Ekki, and all,
> I suspect you are both correct but I would also like to consult
with the
> signal processing experts on the math. Ekki, can you steer me
to some math
> sources on your BW calculations?
>
>
> So I am now interested in the math to see if there is some
correlation I
> could match up. Ekki's analysis is the first I have seen on
"practical"
> bandwidth calculation.
>
> Any other "wizards" out there ?? (Chen...)
>
Realy, Ekki remind us for good practical equation wellknown from
early 1930's wich based on
socalled "channel communication finite distortions" in wired tty
nets. It takes a place in radio too
for all modes wich are using fast pulses changeover as modulation
methode. Its very handy to
define and adjust required bandwidth. Certainly, 250 Hz filter
works fine, but if you switch on AFC!
If you will compare 250 and 350 Hz filters without rig or program
AFC, you will see that 350 Hz
filter is more compartible for rtty 170 Hz shifted signals.
Just belive this, do not go to math! If we start to explore FFT
and Dirak's function, we have start
new "Math Reflector" ~ : )
73! de Kosta UR5FFC
> 73, George .. W1ZT
>
> ----- Original Message -----
> From: "Jay" <jay@ieway.com>
> To: "Ekki" <ekki@plicht.de>; "_Rtty" <rtty@contesting.com>
> Sent: Tuesday, August 28, 2001 4:59 PM
> Subject: RE: [RTTY] Bandwidth of a RTTY signal (was:SO2R RTTY
Radio)
>
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