Re: Barkhausen must be wrong.

On Wed, 10 Oct 2007 14:22:44 -0700, Simon S Aysdie <gwhite@xxxxxx>
wrote:

On Oct 10, 8:48 am, John Popelish <jpopel...@xxxxxxxx> wrote:
The Phantom wrote:
On Wed, 10 Oct 2007 01:37:37 -0400, John Popelish <jpopel...@xxxxxxxx>
wrote:

The Phantom wrote:
John Popelish <jpopel...@xxxxxxxx> wrote:
The Phantom wrote:
MooseFET <kensm...@xxxxxxxxx> wrote:
The Phantom <phan...@xxxxxxx> wrote:
At this site:

http://www.4qdtec.com/singen.html
(snip)
The schematic does show two emitter followers closing the loop. One would
think this couldn't work, but the poster says it does.

Is Barkhausen wrong?
(snip)
The unusual part of this twin T is that the component values
are not the usual C and 2*C, 2*R and R. A ratio of about 5
is used, instead. And the way it is connected, instead of
the usual notch response, it has a broad bandpass filter
response with a peak gain of about 1.089 at about 130 Hz,
with the loading effect of the 1n cap but not counting the
darlington.

You get an A+. My mathematical assistant says the max gain of 1.08893
occurs with a ratio of 4.83152 at a frequency of 129.128034 Hz
So it is possible to get a little voltage gain from an RC
circuit.

See: "Synthesis of Passive RC Networks with Gains Greater than Unity",
Herman Epstein, Proceedings of the IRE, July, 1951, p. 833.

I don't have access to this paper.

Budak also has some coverage of RC circuits w/ v-gain, IIRC.

Presumably one could cascade such circuits.

John

.

Relevant Pages

  • Re: Barkhausen must be wrong.
    ... The Phantom wrote: ... but the poster says it does. ... are not the usual C and 2*C, 2*R and R. A ratio of about 5 is used, instead. ... And the way it is connected, instead of the usual notch response, it has a broad bandpass filter response with a peak gain of about 1.089 at about 130 Hz, with the loading effect of the 1n cap but not counting the darlington. ...
    (sci.electronics.design)
  • Re: Barkhausen must be wrong.
    ... but the poster says it does. ... the usual notch response, it has a broad bandpass filter ... occurs with a ratio of 4.83152 at a frequency of 129.128034 Hz ... circuit. ...
    (sci.electronics.design)
  • Re: Barkhausen must be wrong.
    ... but the poster says it does. ... the usual notch response, it has a broad bandpass filter ... My mathematical assistant says the max gain of 1.08893 ... occurs with a ratio of 4.83152 at a frequency of 129.128034 Hz ...
    (sci.electronics.design)
  • Re: Barkhausen must be wrong.
    ... Budak also has some coverage of RC circuits w/ v-gain, ... Presumably one could cascade such circuits. ... Certainly the voltage gains would multiply, ... 100:1 loading ratio, then 10 stages would get you above 2. ...
    (sci.electronics.design)
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