Symmetry is absolutely required in the Ten Tec scheme because they use both
sides of the filter. One side for LSB and CW and the other side for USB. If
the filter is off even the slightest then you loose either lows or highs in
the passband. LSB and CW are excellent but using the 1.8 Khz filter for USB
can be a problem. I have tried to adjust the oscillators to get a balance
but have not yet been successful. Have not tried the Inrad filters and maybe
that is what I need to do.
> -----Original Message-----
> From: email@example.com [mailto:firstname.lastname@example.org]On
> Behalf Of Paul Christensen
> Sent: Saturday, August 25, 2001 16:11
> To: LJL160@aol.com; email@example.com
> Subject: Re: [TenTec] Passband/ Omni 6+
> > Hi guys- Im crazy about my Omni 6+. I did notice that the USB pitch and
> > bandwidth is not symetrical to the LSB.
> This is common among the Ten-Tec crystal ladder filters. The
> INRAD filters
> do not exhibit this asymmetry, but like most crystal *lattice* filters I
> detect a very slight increase in ringing with them.
> -Paul, W9AC
> TenTec mailing list