1. Re: was: What is a good nature sound recording?

["John Crockett" naturalcontemplative]

Thank you , Raimund for your patience and your assistance. It took me a while 
to get here, but I think I finally understand this at least at a rudimentary 
level. Reducing the drain resistor value does lower the output impedance, but 
that is outweighed by the decrease in signal gain. Oh well.

best wishes,

John


--- In  "Raimund" <> wrote:
>
> 
> Happy New Year!
> 
> I think there is a simple JFET in the EM172. In combination with the external 
> drain resistor, it is a obviously a straightforward common-source amplifier:
> 
> http://www.piclist.com/images/ca/ualberta/phys/www/http/~gingrich/phys395/notes/node91.html
> 
> The voltage gain of such an amplifier is deterimined by equation 5.56 (and 
> 5.57) in the above link. This means that the gain (and therefore the output 
> signal level) will drop when RD is reduced.
> 
> Regards,
> Raimund
>