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Old December 6th 05, 12:05 PM posted to de.sci.electronics,rec.radio.amateur.homebrew,sci.electronics.components,sci.electronics.design
Henry Kiefer
 
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Default "Standard parts" for rf amps?

Sure Jim. I understand you. That was the time where time was cheaper. Once I
programmed a Gauss linear equations system solver on my Casio FX-602P -
having 512 bytes and even left one byte (for extensions ;-) It was with
minimal input help system (Showing the indices to input) and the matrix was
of dynamical order. (Sorry for my bad english)

I can buy resistors and capacitors with 5%, sometimes with 1%. If you build
a rc oscillator with 1% component values, you get an error typical 1,5%. And
then you add the active components with horrible semiconductor strayung
values. Of course, it is possible with feedback structures to linearize and
stabilize such systems.
So, where is the difference between measurement of the component values and
calculating by hand the circuit OR setting the measured values in the Spice
component dialog boxes? The difference is the time needed and the
possibility to make errors.

5% is a real good value for an analog system.

Hey Jim - Why you don't answer my second private message? :-(

- Henry


"Jim Thompson" schrieb im
Newsbeitrag ...
On Mon, 5 Dec 2005 23:53:38 +0100, "Henry Kiefer"
wrote:

Spice is as good as the input is!
Spice is not a Maxwell field equations solver!

You can predict within 5% without Spice?? How?

- Henry

[snip]

Some of us have done better than 5% prediction BC (before CAD)... like
for close to 20 years before I ever saw a computer... and 25 years
before simulation software.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

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