[ARC5] Receiver Filter Adaptor Simple ARC 5 xtal receiver?

[Kenneth G. Gordon]

On 18 Feb 2016 at 18:23, Brian wrote:

> 
> Hello All,
>  
> I think we should listen to Bill.

I absolutely agree.

> One mistake I suspect the rest of you are making is assuming that if you put a
> capacitor in series with a crystal, that is a series resonant circuit. The first
> thing that most of you are missing is that the series and parallel resonances
> refer to within the crystal, not the circuit outside the crystal.

Yes.

> Go look in any
> book on crystal oscillators. In the book you may be lucky enough to find a chart
> of frequency versus impedance. If you look at resonant frequencies, you will see
> that the parallel and series resonant frequencies are very close.

I have seen such a graph and, of course, you are correct.

> For instance,
> see Figure 5.3 on p22 of Marvin Frerking (1978) Crystal oscillator design and
> temperature compensation, Van Nostrand, NY.   Please note email etiquette: I
> have only left attached those emails dealing directly with series and parallel
> crystal resonances.   73 de Brian, VK2GCE. BE, PhD, CPEng, FIEAust  On

Good for you, Brian. I hope your explanation above helps clear the air a little.

I have a fairly thick book on crystal manufacturing written by the military 
during and/or after WWII, which goes very heavily into crystal theory.

Bill's explanations most certainly agree with everything I have read in that 
pub.

Although I most certainly no expert in these (or most other) matters, what I 
have read here during this discussion contained very many misconceptions.

Bill's information was obviously accurate.

Ken W7EKB