AW: [Elecraft] KX1 Crystal Filter Center Frequency a Little Low

[Peter Zenker]

Ladder filters vary both their input/output impedance and their midfrequency
when you vary the bandwith. High level rigs like the K2 therefore adjust the
BFO regarding bandwith (Cal Filter), simpler rigs like the KX1 want the OP
to do this by brain :-)

The impedance  change is why you have more or less attenuation, while
varying the bandwith.

72/3 de Peter, DL2FI    
www.qrpproject.de


> -----Ursprüngliche Nachricht-----
> Von: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] Im Auftrag von David Toepfer
> Gesendet: Mittwoch, 26. April 2006 19:11
> An: Roger Marrotte; Elecraft at mailman.qth.net
> Betreff: Re: [Elecraft] KX1 Crystal Filter Center Frequency a 
> Little Low
> 
> On the low end of the filter it drops down from around 600Hz 
> over most of the range to around 500Hz.  I am sure others can 
> detail why.
> 
> David, K3ZTUE
> .