Re: [TenTec] Omni VII - More IF scheme speculation

[Ken Brown <ken.d.brown@hawaiiantel.net>]

>   Are there any Collins mechainical filters for 9 mhz?
>   
I suspect not.

Mechanical filters use a electromechanical transducer, which may be like 
a speaker voice coil or a piezoelectric device, to convert the IF 
electrical signal to a mechanical motion. The mechanical "signal" is 
propagated through a series of resonant (mechanically) disks, and then 
converted back to an electrical signal using another electromechanical 
transducer. In order for the mechanically resonant parts to have a 
resonance at 9MHz, versus 455kHz, they would have to be really tiny. 
Maybe numerically controlled machining or nanotechnology has gone here. 
As far as I know Collins mechanical filters work only in the sub MHz range.
DE N6KB