[TenTec] INRAD Filter Question

[Bill Fuqua]

Ringing is in the nature of narrow band pass filters. Ringing "length of 
decay" is more a function of bandwidth than that of
skirts.

If you have a 1 Hz bandwidth filter  you can't  detect pulses spaced less 
than 1 second apart. In other words the product of bandwidth and timing 
resolution is always greater than 1 or equal to one. This is related 
to  Heisenberg's Uncertainty Principle.

So with a 1 Hz bandwidth filter you can have 2 seconds of timing resolution 
( .5 Hz) or even 1 second (1 Hz) but not .5 seconds (2 Hz) . So if dits are 
occurring more frequently than 1 per second you cannot distinguish one from 
another. The output from the filter will be a continuous sinusoidal signal.
If the dit rate is less than one Hz or at a period of  greater than a 
second then they are distinguishable.

73
Bill wa4lav



At 11:27 AM 5/23/2003 -0500, you wrote:
>If anything its the other way around. Steeper skirts and squarer
>passband corners mean more ringing, and so the Inrad should ring more
>than the TT.
>
>73, Jerry, K0CQ
>
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